Why are semi trucks in the US and Europe so different? (2018) | Hacker News Reader

Why are semi trucks in the US and Europe so different? (2018)

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Ford used to make some cab-over semi trucks that were very popular in the US during the 80's and early 90's and resembled very closely the European designs of today.

I think it's pretty obvious and comes down to a few things:

* European trucks typically run shorter hauls, and do not require a bunk in the cab as often as multi-day cross-country runs.

* European Semi's need to accommodate all countries' roads and parking lots. This means the much wider range of nonstandard roads, docks, fueling stations and parking lots extends much farther towards the "small" side. Tight streets and parking lots - making it necessary for the truck to be shorter for tighter turns and parking compatibility.

* It has been proven that a cab-forward design is safer for avoiding accidents directly in front of the vehicles, something that is more focused on in the EU.

* The least obvious but possibly the most relevant reason why it remains: Having and ingraining differing standards makes it harder for a single competitor to play into the both markets. EU is largely locked down by EU manufacturers since any US manufacturers would have to significantly change their design and production to sell there.

The fuel economy point seems to be a distant consideration since the majority of drag economy comes from the trailer and not the tractor.

Although runs appear shorter in the EU, they're still multi-day. Lisbon to Edinburg is a 2000 mile drive. Most drivers kip in their cabs, not at home.

IMO it's entirely down to the road networks. Driving across the US is like driving across one very broad road network. Driving across Europe is like driving on many fragmented, narrow road networks.

[citation needed] Europe has a network of motorways. Last mile is a different story, probably the whole story.

Europe consists of 44 different countries with sometimes vastly different developed, and funded, infrastructure.

There is a big difference between the motorways in a country like the Netherlands vs those in Moldova [0]

There is often also vastly different regulations in terms of vehicle safety requirements, and many other differences, the combination of which also leads to quite different per capita traffic deaths [1]

[0] https://landgeist.com/2021/09/07/the-best-and-worst-roads-in...

[1] https://www.euronews.com/2018/12/07/which-countries-in-europ...

The article brings all of this up, as well as the prevalence of "sleeper" cabs in US but not EU. This all seems pretty obviously likely to contribute.

One non obvious thing in article; apparently up until 1986 both US and Europe had a strict limit on length of trailer + truck, which is a clear incentive to shorter cabs (gets you more trailer). In 86 US relaxed this, correlates pretty well with the fall off on cab-over designs.

Sleeper cabs are popular in Europe too. But sleeper part is rather tiny. Yet trucker still sleep in them for weeks.

Fair enough, that was sloppy terminology of me!

And that is the difference between a hired employee and an owner-operator.

I doubt euro trucks had different chassis designs if trucks were owned by truckers.

But trucking in Europe is a mess with massive companies squeezing truckers and importing cheaper workers from wherever to keep salaries low and conditions shitty.

At least one sector where Europe out-big-corps US?

Rest assured: the American trucking industry abuses workers too.

I mean, I'm sure European truckers would love a full kitchen, a shower and a double bed if they could get it. But the length limits would still be a problem and it would be hard enough to stay competitive without having to refuse the standard length trailers.

You're not going to see a full kitchen and shower in a standard sleeper cab. You'll get one or two beds, maybe a dinette, a microwave, and a fridge. To get the kitchen and shower, you're going to have to go custom. Going custom, you're only limited by money, space, and regulations.

And the 'dinette' is literally a fold down table in front of the bunk.

Cabovers had all of those things too.

Most truckers in Denmark own their own trucks?

In NL plenty of truckers own their own truck.

Because US truck drivers are well known for their amazing working conditions and financial independence?

In the US a lot more truck drivers are owner operators, so yes to the financial independence part.

Is that true? Contractors supplying their own tractors is the norm in Ireland, at least.

I imagine the truckers in Europe are also smaller than their American counterparts.

In the US I see many dump trucks pulling trailers with a very long extension rod (the thing that connects to the motorized truck; I don’t know the actual name for it). Even on the Puget Sound I see them entering the ferries with a ton of wasted space.

Do you have any idea why dump trucks make them self so much longer without providing any more load capacity?

Edit: Here is an example. You could fit another truck in the space between the truck and the trailer: https://d2uhsaoc6ysewq.cloudfront.net/53248/Dump-Trucks-West...

Maneuverability. There's no articulation point between the cab and the dump. The gap between the dump and trailer allows for very tight turns.

I would guess this has to do with maneuverability. It's very hard to back up a trailer when the drive vehicle wheelbase is long compared to the trailer. Adding a bunch of tongue length helps a lot.

The bit between the truck and trailer is a drawbar. As mentioned, it is indeed mainly for manoeuvreability. In Australia, that combination is called a 'truck and dog', the dog being the rear trailer. The front axle(s) on the dog are steerable by the drawbar. The upshot of this combination is that you can tip the truck without having to disconnect the trailer, by 'folding' the combination up on itself, turning the whole lot into a U-shape.

As for load, these trucks are completely loaded, there is no waste. This is simply because the things that a tipper transports (bitumen, dirt, grain, gravel etc.) are very dense. Load limits, at least in Australia, are based on the amount of axles under the vehicle, so the only way to increase the load capacity of these trucks is to increase axle count. Example: https://www.aeitransport.com.au/biggest-load-to-be-moved-in-...

The image of the truck and dog you linked seems especially long. This might be a specialised setup for roadworks, where the driver can actually tip the load (in a controlled manner) through the drawbar and drive the dog over the top of it. The longer drawbar would leave room for the tipping body on the truck to raise completely, and also lower the angles experienced by the hitch if the driver offloads too much material between the truck and dog.

I'm late to this party, but I didn't see an answer that got to one of the big reasons for the large distance between a truck and trailer. There are laws about weight, specifically measurements called bridge and inner bridge.

My father and grandfather spent a lot of time reading the laws and charts every time they'd build out a new truck or trailer to try and maximize what they could haul. More axels allows for more weight, that seems obvious, but more distance is required between the truck and trailer as well.

It gets to be a really fun problem when one state wants a tongue/drawbar length of 28' and the neighboring state says that is too long and only wants 16'. What to do? Make the length adjustable and switch it over at the state line.

The last and biggest combo they ran was over 100' long, 9 axels, 34 tires and hauled 80,000 pounds. I don't remember the gross weight.

It has been proven that a cab-forward design is safer for avoiding accidents directly in front of the vehicles, something that is more focused on in the EU.

Ironic, because back in the 70's when there were more CoE designs driving around in the US, it was generally known through crash tests that CoE cab trucks were a lot less safe than conventional cab trucks in front-end collisions because of the driver's distance to the collision.

If CoE trucks have gotten safer in front-end collisions, it's because a lot of engineering work has been done to mitigate this old problem.

OP said cab over engine is safer for avoiding accidents (probably because of increased visibility). Not necessarily safer when an accident occurs.

Correct, it has been proven many times that the lack of blindspot directly in front of the vehicle (to the driver) is the main factor. New "stubby" nose school bus designs greatly improved this over existing ones which were closer to a semi. Lately, front cameras and warning systems have made this less of a concern but it still remains the case.

CoE are better at _preventing_ collisions because of a better field of view, but I'm not sure how good safe they are when there is a collision

Spoke with a trucker about this very issue. He started out driving CoE trucks and said when there's a crash the driver is ejected out through the window. Now this was before the days of airbags but that would be enough to discourage their use. He said it got so drivers refused to work at companies who used them. However it was the desire for increased fuel economy that finally ended their reign.

No safety belts?

This. However... Might help if you drive your semi into a brick wall at speed. Just because you are more likely the truck goes through the wall before the cab does. Which happens, someone drove a semi into a data center of ours. Fortunately DR response included this type is disaster.

I've no doubt that the old CoE trucks from the 60s were death traps. But I'd be interested in seeing what the difference is between a modern European Volvo (one of the few companies who build both types) and a US version. I would be very surprised if the difference wasn't negligible. Putting the engine out front is a brute force way of providing safety which isn't necessary with modern design.

Maybe dumb question- I've never been in a truck. Wouldn't the distance from seat to window be ~pretty much the same whether it's CoE or conventional?

There's a hood in front of you for conventional, and I guess crumple zone deceleration comes in to play there? But as this article mentioned US trucks have a much higher average/top speed so you're probably just as likely to go through the window.

There’s safer as in “less likely for the driver of this vehicle to cause a crash” and there is safer as in “in the event of a collision, it is safer for the driver to be in this car than that one.”

Neatly distinguishing the EU from the US.

The 70's were 50 years ago.

Back then we barely had seat belts, let alone airbags, adaptive cruise control, automated braking in case of collision, blind spot detectors, etc.

Most of that tech is not commonly found on a semi-tractor anyhow.

It's all legally required in new tractors in the EU.

Testing by Volvo determined that in a front-on collision the engine of a conventional cab ended up in the cabin crushing driver. This was the primary reason for CoE adoption in Europe. Similar to cars before safety cells and crumple zones became the norm.

Common perception in America (contrary to actual testing) believed having all that bulk in front made a conventional truck safer.

> > It has been proven that a cab-forward design is safer for avoiding accidents directly in front of the vehicles

> Ironic, because back in the 70's when there were more CoE designs driving around in the US, it was generally known through crash tests that CoE cab trucks were a lot less safe than conventional cab trucks in front-end collisions

That's not ironic: safety in collisions from one direction and safety for avoiding collisions from the same direction are very different and often opposed things.

Other than the collision part addressed by sister comments, the shorter designs also help reduce blind spots. There ‘s a lot more than just the driver’s safety.

> * European trucks typically run shorter hauls, and do not require a bunk in the cab as often as multi-day cross-country runs.

I find it hard to believe. There are tons of trucks, having multi-day cross-country runs. I know a few truckers, they all have. They sleep in their cabs. Sometimes there are 2 truckers, so they can swap whenever limits reached.

I see trucks from different countries any time I hit the road. If you ride on German autobahn, there is a never-ending stream of trucks from different countries.

Also cargo rail is supposedly not a prevalent in the EU as it is in the US. (Vice versa for passenger rail.)

EU has a LOT more truck volume (both in terms of per capita and percentage of freight shipped by truck). This has some complex and not so obvious implications on how long things get hauled. The smaller trucks also make it more economical to do trips between hubs vs hauling across 3000kms (which is reasonably common in the US). Smaller trailer capacity (due to EU length restrictions) and increased depot/truck distribution means a heavier distribution towards shorter hauling.

Are there any routes in Europe as long as the US coast-to-coast haul?

Quick look at a map will tell you yes. Might not be as common, but I am sure fruit gets delivered to Finland from Andalucía by road.

I'm sure trailers make the trip. But are they pulled by one tractor the whole way?

Yes.

But Finland has only 5 million inhabitants, so the volume is nearly negligible on European scale. The big population centers are closer to each other and even agricultural hotspots.

European semis all have a bunk beds, for two. They don't feature a kitchen though, and in the evenings the truckers gather in truck stops which serve humongous servings. These truck stops are all along the freeways all over Europe.

There is a maximum vehicle length though, and a maximum weight, the former ensures vehicle maneuverability, the latter serves road stability, bridge specifications, optimized no-waste parking provisions for pass-through parking spots in said truck stops edit: and ferry capacity. Ireland, Finland are connected by Ferry.

Manufacturing is pretty much internationalized, reusing parts and designs globally. Freightliner and Daimler are one company, for example.

Fuel economy is indeed a point, albeit the combo of trailer and truck define the overall fuel economy. As the trailer usually is equivalent to a standard 40ft container, the ideal truck has a boring standard form, too.

The text is German, the pictures are self explanatory-ish though wrt optimal and sub optimal wind résistance: https://en.vda.de/dam/vda/publications/FAT-SCHRIFTENREIHE%20...

This is completely off topic, but does anyone know of a way to get a top-tier search engine to return the best results across all languages rather than the language matching that of the search query + English, as they are wont to do?

If there is a wikipedia entry on the topic, use the interlanguage links to find the most commonly used words for that term in a foreign language.

Yes I agree this is what I do all the time and it works in most cases

IIRC Google had provided search with translated query. It was useful. Anyone know alternative?

I do a lot of research for historical things and often want results from other languages and have found on Google if you search for something and then click the settings icon and then click languages you can choose multiple results for "Currently showing search results in:" which will give you results in the languages you choose.

I typically do this in incognito windows as I do not always want for instance English and Italian results.

Have u seen any studies on how to add a detachable battery pack to an existing truck configuration?

For example, a 2mx2mx0.5m pack can be slotted between the cabin and trailer.

A 2mx6mx0.25cm can be laid on the roof ?

Etc..

(I have seen demos of an Australian truck where the fossil engine is removed, and the pack is inserted from the front.)

99.9% of US trucks do not have a kitchen either, unless you count a microwave as a 'kitchen'. Truck drivers also stop at truck stops in the US for food, fuel, a shower, sleep, however many long haul trucks are now team operations - one guy drives and the other one sleeps.

There is something like a 70-90% parts commonality between a sleeper cabover and a conventional tractor, indeed - the only parts that differ are body, frame, and a couple interior pieces - even drivetrains are shared - and commonly shared between europe and NA - though European engines do not have the best reputation among US drivers (neither the Volvo or Mercedes Class 8 engine is well thought of - parts are expensive and take a long time, and sadly they're needed with alarming frequency). Indeed, many interior parts can be shared between a cabover and conventional truck, including the dash, and most of the interior appointments.

Iceland and the Faroes are also connected via ferry neither are in the EU but I think they also have the cap-over as the more common design. However I don’t know how common it is for semis to board the Norröna as the voyage is 1-2 days.

Just because the distances are shorter doesn't mean they drive to the destination and back again.

They could easily have multiple destinations they drive to one after the other, with different cargo each time

European trucks cross multiple countries during a trip with the same driver. In France, by looking at the vehicle plate, trucks come from Spain, Portugal, Lituania, Poland, Germany, etc Those are 2 to 3 days trips.

This. In the EU, trucks drive from Finland to Portugal, same driver. Americans really don't get Europe.

The opposite is also true. Europeans often do not understand how just how big America is.

And forget that Canadian and Mexican trucks are also transiting the borders.

Literally moving goal posts

USA's land area is smaller than Europe, but not by much, so I think it's fair to treat it as a non-factor. But the story changes if you also include Mexico and Canada...

I suspect all of this is wrong.

The maximum length of an articulated vehicle in Germany (and most of europe) is 16.5m or 54 ft. [1]

The maximum length of a vehicle in California is 65 ft. California is one of the more restrictive states when it comes to vehicle length simply because of the age of the road network.

The longest vehicle you'll see in the states are turnpike doubles, which are around 130 ft long, the longest total permitted vehicle length in Europe is 65 ft.

The US used cabovers before vehicle length rules were liberalized, and thats why we don't anymore, drivers prefer conventional trucks, the ride better, largely handle better, and are safer for the driver.

[1] https://www.itf-oecd.org/sites/default/files/docs/dimensions...

Sweden and Finland allows up to 25.5 m.

I did indeed say, most of Europe.

Incidentally, Finland and Sweden constitute something like 20% of the EU's total area, and both have relatively small urban centres scattered all around the place.

It's pretty natural both have somewhat differing regulations in regards to transportation.

"The maximum length of a vehicle in California is 65 ft. California is one of the more restrictive states when it comes to vehicle length simply because of the age of the road network."

Sort of.

https://dot.ca.gov/programs/traffic-operations/legal-truck-a...

The STAA (Surface Transportation Assistance Act of 1982) trucks can have unlimited length cabs but are primarily limited to interstates and marked state routes.

As someone who drove trucks and was licensed in California - California has other rules that limit, including axle to tandem limits, and not allowing triples or turnpike doubles (both of which are allowed elsewhere, but not federally required). The unlimited length of tractor has practical considerations too, there are reasons why 95% of the long haul fleet is conventional condo sleepers (notwithstanding the folks who drive a RV style sleeper, with a little living area in it) - and 95% of the local fleet are conventional day cabs, mostly driver preference.

So while yes, I used California's state limit as an easy from of comparison, because it is one of more restrictive western states - you're correct in that the STAA allows a longer tractor. In the end, the rules are lightly enforced - but the state limits guide the total length of combination. It's why (for example) you almost never see doubles being pulled by anything other than a day cab.

Bit of a shitshow of authorities for any given piece of road but generally speaking it's the city streets and town-level jurisdictions that get restrictive moreso than interstates and major highways.

There is also the weight factor - even if you could legally have 90ft trailers and 25ft cabs, it would probably put you over the weight limit for many roadways and negate the savings.

" drivers prefer conventional trucks, the ride better, largely handle better, and are safer for the driver." I drove truck in the 90's and the joke back then was "cabover driver's were the first to arrive at the scene of an accident".

Are they better for pedestrians, cyclists, bikers and other drivers, though? I imagine it's much easier to see things in front of you with the cabover design.

Personally I'd optimize a bit more for everyone else's safety, since you know, there's more of them. Plus a semi is a multi-ton missile going 90kmph.

Can you share evidence they aren’t better?

School buses typically have a large nose in front of the driver. Are they unsafe?

I can't really share any studies, but some people seem to have more info: https://news.ycombinator.com/item?id=30195371

Intuitively it would make sense that being able to see in front of you with no obstruction would have an impact on safety. How much, I can't say ¯\_(ツ)_/¯

> School buses typically have a large nose in front of the driver. Are they unsafe?

Guess what, European buses don't have a nose, either :-)))

Those hunking blocks of sheet-metal in the US that you call school buses (alternatively, prisoner transport)? Well, yeah. European buses share much with their truck counterparts, except the massively better visibility all around:

https://www.mercedes-benz-bus.com/content/dam/mbo/markets/co...

Some school buses have a large nose, but many school buses are rear-engined and have flat fronts.

School busses have a regulatory carve out for pollution controls and seat belts. School busses are most dangerous new built passenger vehicles allowed on the road in the US with more than three wheels.

Yet fatal accidents involving school buses are vanishingly rare.

They do have higher standards for the drivers

The standards are basically the same as for a commercial truck driver. The edge cases of what they're willing to accept are slightly different.

School busses only rarely get on the highway, most collisions happen on low speed secondary roads, which are rarely fatal. Plus the sheer mass of the bus means it doesn't get thrown around as much as a car would in an accident.

How dangerous?

Truck accidents where the truck plows into another vehicle are relatively rare. We know because they're recorded by the DOT, and kept as statistics. You're more likely to take them our with the trailer than driving over the front of them.

I have seen four wheelers do all sorts of stupid shit around trucks, stuff that endangers everyones lives, I want that extra little bit of hood in front of me.

I agree that going to a hybrid model is good, where its a short nose conventional cab, like the Cascadia - rather than a long hood-high hood model.

> Truck accidents where the truck plows into another vehicle are relatively rare.

Interesting, in Germany there happen 4 truck accidents on highways every day, every third one of those is a truck driving into the end of a traffic jam [0], in total they apparently cause more deaths than speeding [1].

[0] https://www.autofahrerseite.eu/sicherheit/524-lkw-unfall-sta...

[1] https://www.faz.net/aktuell/wirtschaft/lkw-unfaelle-fordern-...

Driving a cabover would seem to not help in those situations, somewhat obviously.

A cabover has better close up visibility, not distance.

These day even very cheap car (Nissan micra say) has auto brake and track alignment. Not e-car just normal one. If the stat is so bad in German can this help? Seems inexpensive technology now like abs etc.

It's there, but there are issues:

https://trid.trb.org/view/1756275

< California is one of the more restrictive states when it comes to vehicle length simply because of the age of the road network.

What makes the road network in CA so old compared to eastern states that had roads built so much earlier?

California has A LOT of roads given its size, and density is focused in the big cities, so you have a lot of country roads to maintain with limited revenue to maintain them.

A lot of highways in California have warnings like "no services for 100 miles" and you won't encounter a lot of other vehicles (similar to Nevada and Oregon adjacent).

California started building a state highway network before the east cost did - also it has mountainous roads that have restrictions on overall length, simply because of curve radius.

The first freeway ever was made in California. California is a huge state with widely dispersed population centers (since well before cars), and population growth only really took off around the time of WW2 and the widespread production and adoption of cars and trucks. It’s had a very road and car centric culture since then.

> The first freeway ever was made in California

What road is that? How about the Pennsylvania Turnpike?

That is a toll road and highway, not a freeway. Definitely some definition slicing going on - the 110 in SoCal was the first recognized freeway [https://www.motortrend.com/features/1804-americas-first-free...]

Differences are typically that a freeway is designed and constructed to allow maximum speed and no interruptions/stops (hence all the on/off ramps, lack of lights, lack of toll booths), and is available to the general public for use without significant restrictions or costs.

Which make it far easier to use, faster, etc. the interstate highway system was designed largely using the model.

AFAIK only in California are toll-free, multi-lane highways called "freeways," so there may be no end to the definition-jockeying. If maximum speed is a necessary factor then CA may have no freeways at all remaining.

Haha, yeah the whole ‘high speed’ thing is pretty much only at 2am on a Wednesday in many parts of California now.

One key thing at the time I believe was the grade separation/right of way stuff, which I think had only occurred on toll roads for any distance before.

Previously almost all highways ended up having to stop or intersect with other roads (and hence stop signs, or traffic lights, or whatever). Most highways are still that way, outside of major arterials.

Most major arterial highways are the same as freeways now everywhere of course, but I think that’s more about economic factors. California I think was just the first mover on it (and got exposed to those same economic factors earlier than most).

At the time (and still does, though it gets less press now), California was a huge oil state, and was at the forefront of designing and building refineries too.

European cabovers have beds[1]. Sometimes a double bunk[2]. But they don't have a living area with kitchen etc. like American conventional trucks often do.

> makes it harder for a single competitor to play into the both markets

I don't think this is the case, because many of the top European and American brands are owned by the same conglomerates. For example Paccar owns DAF in Europe and Kenworth and Peterbilt in America.

[1] https://www.youtube.com/watch?v=y3O3ixew1kA

[2] https://www.youtube.com/watch?v=flScrV0pQwU

Another reason is that longer trucks are harder to overtake on motorways, the longer the truck the higher the risks for accidents. Europe has smaller highways and country roads.

Furthermore truck logistics in the USA is mainly based on FTL (full truck load), which means the truck just drives from A to B. In Europe LTL (less than truck load) is more common, which means pickup and delivery on multiple stops. This requires a better maneuverability, hence shorter trucks.

LTL also makes more sense with shorter trailers, since you can unload and reload the trailer quickly without having to play Jenga at the dock. It also encourages depot-to-depot runs vs supplier-to-client, which leads to the average trip length being shorter.

Another factor unmentioned is the amount of independent truckers in the US who own their trucks and who primarily do longhaul sorties spanning a week or more. Can't find any data on this but it is a very commonplace thing in the US for truckers to live in their trucks more than their homes and I'm not sure that is the case in the EU.

Truckers having their own trucks is history in the EU. Well almost. Nowadays the whole truck busines is in East Europe. with a wide variety of big companies. Mostly if not all international EU transport is driven by trucks from those low wage countries Poland, Bulgaria, Romania. You see them everywhere. From Ireland to Portugal to The Netherlands etc. Most highway parking stops are filled trucks from those countries. They live in their trucks for weeks if not months. It used to be quite dirty environment on those stops. With many eating next to their trucks. It's getting better now.

This Tesla was pushed for half a mile seemingly oblivious to the driver of this conventional cab semi.

https://youtu.be/A5GePY23FxI

In Australia I've found the European style far more common, contrary what is suggested in the article.

While we're on the topic of trucks, I've always had this pointless desire to get a non-synchronous transmission truck driver's licence. I just think it'd be fun learning to drive an 18 speed crash box with double clutching and clutch brakes - something I imagine will soon be a thing of the past. Regrettably, there's no real reason for me to get it.

For now, the rational part of my brain is keeping this in check.

The whole article seems full of conjecture and generalisation.

A big example:

> Another advantage of a conventional cab design is that the truck can be more economical. Surely they usually pull heavier loads, but if there were two trucks, one a cab-over and another one a conventional cab design, and they had the same powertrain and the same cargo, the conventional cab truck would most likely use less fuel. Of course, that is just in theory – in reality there are too many factors to consider.

I don't know... power, load and fuel economy is the kind of data that's extremely available about motor vehicles... this is something we can't figure out? Or were they just writing hearsay to push content and get clicks? ("Subscribe to our facebook. Loads of content coming soon!")

> Or were they just writing hearsay to push content and get clicks?

I think this is a very uncharitable interpretation. It has been decades in the US and Canada since cab overs fell out of style and thus you can't buy ones that take the same trade-offs as your average conventional truck. Comparing trucks designed for completely different regulatory, geographical, and practical constraints isn't going to net something useful so we have to make estimated guesses. It seems like it would be similar to comparing the fuel economy of an an unladen F-150 with an unladen F-350; They might do similar things but in practice there are so many capability trade-offs that it isn't a particularly interesting thing to do. As they said:

> that is just in theory – in reality there are too many factors to consider.

The most aerodynamic COE have higher drag coefficients than the most aerodynamic conventionals, the big flat front produces a large high pressure area.

Lots of conjecture. The reality is most of the drag is encountered on the trailer, tires and underside. This is the reason you now see "skirts" on almost all trailers, and the general reduction in distance between tractor and trailer and not long airplane-like tractors.

More important to fuel economy is maximizing cargo per trip, as having 20% more cargo in the trailer has no impact on aerodynamics and minimal contribution to rolling resistance and acceleration losses. This is the main argument against the length restrictions in the EU. Longer trailers + more aerodynamic tractors would lead to a significant increase in fuel economy - albeit at the cost of road safety: EU records nearly identical deaths per year for trucking related accidents as the US - around 5000 - but has 300% as many trucks on the road and 50% more population than the US.

Are you aware of the Truck Simulator series of games?

I have heard of it but haven't really looked into it.

There's something appealing in the physical labour of feeling and manipulating the clutch and gearbox, that a simulator might not capture, but I will it check it out.

Big Mutha Truckers?

https://en.m.wikipedia.org/wiki/Big_Mutha_Truckers

Big Rigs: Over the Road Racing. At one point it was the lowest rated game ever on metacritic.

The opponents don't move, there is no clipping of obstacles, and once you cross the finish line you are greeted with a screen proudly saying "You're Winner!"

https://en.wikipedia.org/wiki/Big_Rigs:_Over_the_Road_Racing

Let's not forget the missing speed cap for the reverse gear. You can accelerate to over 1000 mph and fly off the map.

Obviously, the game developers were unexperienced and couldn't deliver a functioning product. What's amazing is that the company had the audacity to sell it in stores nevertheless.

> I've always had this pointless desire to get a non-synchronous transmission truck driver's licence. I just think it'd be fun learning to drive an 18 speed crash box with double clutching and clutch brakes. However, there's absolutely no reason for me to get it.

> For now, the rational part of my brain is keeping this in check.

You're not alone! I have the exact same desire.

I have a lot of friends that are recreationally pilots or boat captains so I don't think it's that strange.

In Australia, I think the default style has changed over time. Back in the 1980s, Mack and Kenworth were the dominant brands. Now there's more of a mix, with the likes of Volvo and Scania doing well, but Mack and Kenworth are still in the top 10.[1]

[1] https://www.trucksales.com.au/editorial/details/2020-truck-s...

I see. It could be a metropolitan/regional divide too. Most the trucks I see are metropolitan traversing from the port to inner city destinations.

I imagine the composition is different on, say, the Nullarbor plain.

That's an interesting point about the metro/regional divide. It could be that livestock haulage is more invested in the "conventional" style. I was quite familiar with one local haulage company growing up, and checking their website it seems like their entire fleet is still "conventional"![1]

[1] https://www.martinshaulage.com.au/

Volvos are popular in the US and have a conventional cab design.

> I just think it'd be fun learning to drive an 18 speed crash box with double clutching and clutch brakes. However, there's absolutely no reason for me to get it.

I guarantee you would quickly abandon this double clutching "fun" at real trucking job because it is very tiring when you need to change gears a lot for example when there are a lot of intersections and turns. AFAIK most/all drivers in USA don't use clutch at all (for anything other than starting and stopping the vehicle) in non-synchronized transmission trucks for that very reason. Switching gears without clutch is easier and faster when you learn how to do it smoothly.

That being said... I strongly suggest you to try either American or Euro Truck simulator games. If you have a steering wheel and gearbox controllers for your computer, you can indeed have a lot of fun and gain some gear shifting and big truck driving skills at much lower cost than in real life while still having kind of real feeling.

I used to do that in my old beetle that had a clutch that was quite weak. I only used the clutch in 1st gear, the rest of the upshifts by ear. There was enough slop in the gears that you could do that all day long and never miss.

Were they timed to make it reasonable to go directly from n to n+1 or did you have to shift to neutral, wait, then upshift?

I have a not-so-old Audi with a known-bad gearbox w/ faulty synchros and because it is a turbo you really can’t upshift in that band when/where the gears are lined up without losing too much power so I have learned to time how long I should wait in neutral (for the RPMs to drop) before completing the upshift. Non-sequential downshifting after slowing down from a higher gear is much harder though - you really have to play it by ear based off the sound/RPMs and the current speed both. And it’s a six speed with considerably less slop than the old Beetles used to have.

The trick is to match the rpms as the engine drops naturally you just slot it in gear at the right moment. If you do it often enough at some point you don't even notice anymore until you try to drive another vehicle, at which point hilarity will ensue.

Those old beetles were just four speeds, pretty beefy gears. I never managed a good downshift though, I would cheat and very briefly depress the clutch so it wouldn't slip. Do it too long and you'd get that horribly expensive smell. I was dirt poor and got the car for free so I really couldn't complain. Baby blue. And it taught me to be very careful on wet surfaces with a rear mounted engine (took out a bicycle stand with it in front of one of the busiest coffee places in Amsterdam West, "Tramlijn Begeerte" (dutch translation of a 'streetcar called desire'). Funny little car.

For the downshifting, you can speed things up if you spin up the input shaft by putting the gear selector in neutral with the clutch engaged (foot off it) and rev the engine to increase the speed of the input shaft, then clutch back in, and select the lower gear (now with the input shaft going faster [as is needed], the synchros have much less work to do to engage the lower gear).

I had an old Alfa Romeo that was fantastic overall but had a pretty terrible transmission, especially when cold. You do learn quickly how to get by. :)

I do that regularly in all stick shift vehicles (rev matching). It's a lot more challenging without a synchro at all, though!

This works for upshifting too, it's known as double clutching.

If you have a turbo diesel it's a good skill to learn as you can shift smoothly while still keeping the turbo spooled up and not cause as much wear on the gearbox.

You can get a Truck Simulator game, and purchase gaming equipment for it. You can have a real life steering wheel, shifter, and pedals.

Image of such a setup: https://imgur.com/xUdS3wD taken from the trucksim subreddit.

How is that rational? A truck driver's license can't be too expensive, even if you hardly use it. It's probably one of the easier things to have on your bucket list.

Depending on where you live, there might be on-going fees (regular medical, psychological exams, etc, paid by the license holder). This kind of license is assumed to be used for revenue generation, so the fees are not supposed to be a problem.

If they just want to get it once ongoing cost is not a concern.

I looked into this. It's very doable and easy. It's funny but the actual thing that annoys me is that if you want to get an A when you already have a C and M1, you then need to do the C and M1 tests again. And to be honest, the M1 written test is pretty hard (like at least 10x harder than the C). I obviously passed it on my first attempt but I definitely know people who decided to just keep their out of state motorcycle license instead.

EDIT in response to reply: I actually don't think it's obvious that if you get C, M1, and A separated by a month that you should do 1+2+3 tests but that if you get C+C separated by years you do 1+0 tests.

Obviously?

What do the letters mean?

License classes. C (at least in my area) authorizes <26001 lb, B more, and A anything legal to put on a highway. I assume M1 is a motorcycle license or endorsement.

A friend of mine did just that when he moved to Australia and changed job. He has a masters degree, but started working as a untrained manual labor hand. Got the company to pay for his truck licence, (because they needed drivers) and fulfilled is childhood dream. Was driving trucks and helping out on the factory floor for a couple of years, then became the transportation manager and is now the general manager at a different company. Quite an interesting career path.

In college, I drove an ancient car with a failing manual transmission that required double clutching to work. It was not fun.

Tried driving an old double-clutch truck - the clutch pedal was extremely hard with an absurdly long travel length. No power steering either. Very sore left leg and arms after navigating through a small town.

Those Australian "road trains" that run the outback definitely use more American style cabs, but I guess for obvious reasons.

Sometimes you can take a CDL course for cheap. I did years ago and it was fun.

I wouldn’t get the license though as even minor traffic violations can become a pain in the butt.

I've always had this pointless desire to get a non-synchronous transmission truck driver's licence. I just think it'd be fun learning to drive an 18 speed crash box with double clutching and clutch brakes

I once had a commercial license paid for by a grant program as part of that job. I had to give it up when I moved states and no reason to redo it. I regret it a lot because it was useful in many ways. Probably different in Australia, but having a odd set of skills never hurt my life.

Hey I was driving those in the Swiss Army, 2dm's they were called and a lot of fun once you got the coordination right, it's over 30 years ago... here in egypt I've seen preteens driving such trucks which brings a thought and suggestion, why not come to less "developed" countries to do such things on your bucket list... though I'm sure even your government doesn't have ubiquitous oversight in your "outback" so probably no need to leave your "island" :-)

> I've always had this pointless desire to get a non-synchronous transmission truck driver's licence. I just think it'd be fun learning to drive an 18 speed crash box with double clutching and clutch brakes - something I imagine will soon be a thing of the past. Regrettably, there's no real reason for me to get it.

Look out. I know a guy who caved in and learned. Then decided he doesn't like computers all that much and he doesn't _really_ need that software engineer salary, especially if he can cut on rent by sleeping in his truck.

It sort of depends where you are - I think most of the ones people in cities would see are cab over but the moment you head rurally it’s almost exclusively conventional - Kenworth and Western Star are by far and away the biggest brands. Try driving up or down the Newell Highway - conventional would outnumber cab over 10-20:1

Driving a road ranger gearbox is a lot of fun. And a jake brake makes an awesome sound! I agree with the comment below me - you almost never use the clutch, just match revs to gear. It’s a nice skill, you can do it in any manual vehicle but you’re more likely to torch the transmission in the average car - Toyota landcruisers are good practice though

I was going to recommend taking the three-day Skip Barber open wheel class, but looks like they've switched that to the Mygale Formula 4 cars with a sequential gearbox. When I did it, they were Dodge powered with the old straight-cut gears with dog rings.

I suspect you could find a Formula Dodge or Formula Ford racing series with an intro class if you just want to learn the gearbox aspects, plus then you can learn to rotate a car with the steering wheel, the gas, and the brake pedal. ;)

Interesting. In Sydney i would say not. But this is based on anecdotal observations and as we know we can be bias.

I remember when Mercedes Benz bought Freightliner, the major US truck manufacturer,in the 80s. The Mercedes Benz engineeers were astonished to see how UN-sophisticated the engineering of Freightliner trucks was. Example: no assisted steering!!! That choice was justified as more macho. I was told that assisted steering was not manly enough...

There can be value in simplicity - fewer things to break and easier to repair.

Exactly. The irony of Mercedes-Benz engineers marveling at how unsophisticated a simply-engineered vehicle is brought a smile to my face. Most owner-operator truck drivers want to be able to fix and maintain their trucks on their own, not bring the truck into the dealer every 3 months like some temperamental S-class.

Although I guess Mercedes was still pretty reliable back in the 80's.

You really think that owner operators repair their own trucks? That doesn't make any economic sense. This is not a hobby, they need to drive to make money not to play truck repairman.

I'm always astonished how US Americans try to justify poor engineering with "advantage of simplicity". It's like arguing that you want to program using punch cards because that makes you feel closer to the machine and you have a "physical" copy of your programs.

There are many areas of the US where a truck driver might find themself hours away from a mechanic or tow truck. I assume there is some value in fixability, assuming the reliability is not too much less than a less fixable truck.

Do they want to spend their time doing it? No. Do they have a choice in most of the country? No. Trucks don't conveniently break down at the mechanic's shop.

Simplicity also means less time in the shop when needed too, they usually charge by the hour. Also in the 80s I could totally see that. On the side of the road, hood up fix it right there. Remember they probably had CB radio which is limited range, no phone and the closest town is 50 miles behind you.

Also depending on the job it can make very good economic sense to DIY. My brother in law just had to fix something on his car. They quoted him 2500. He fixed it himself for about the cost of some used parts (80 bucks) and a half day of his time. Trucks are no different.

You really think that owner operators repair their own trucks? That doesn't make any economic sense. This is not a hobby, they need to drive to make money not to play truck repairman.

I've known several owner-operators, friends of family mostly, and yes, they routinely strip and repair their own kit. It's a lot cheaper and very often faster than taking it into a shop.

I'm always astonished how US Americans try to justify poor engineering with...

O_o

>US Americans

This is a side note, does this bother anybody else? I'm at least a teensy bit bothered by it. I know the point is to reduce ambiguity between the U.S.A and Latin/North/Central/South America, but it still feels a bit condescending, like we're not even allowed to have a unique name anymore or even have a say in we should call ourselves/be called in our native language (and it doesn't help that the only time I hear "US Americans" is when someone is talking shit about us). There's only one country on the continent with the word America in its name. I'm curious if I'm the only one who feels this way or if I'm overthinking it.

> reduce ambiguity between the U.S.A and Latin/North/Central/South America,

And the continent 'America'.

Just for comparison: what do you think 'South Africa' (the country, not the region ;) should be called?

South Africa? I would call it South Africa if that's what they want to be called. I definitely wouldn't call citizens of South Africa "RS Africans" or something unless they preferred that for some reason.

In Romance languages, the continent is known as the supercontinent "America", but in Germanic languages (like English) and other languages that borrow from it call them the "Americas" as two continents "North" and "South" America. So, for people to bring it over as 'America' can sometimes be seen as pedantry instead of insightfulness.

> but in Germanic languages (like English)

Well, yes, in theory you could use 'Amerikas' in German, but nowadays that's mostly because of a bad translation. It actually is correct German to speak of 'both America' - 'beide Amerika' (in singular).

https://www.duden.de/rechtschreibung/Amerika

> So, for people to bring it over as 'America' can sometimes be seen as pedantry instead of insightfulness.

Of course it is pedantry.

Hah, when I hear "beide Amerikas" I think of political divide within the US.

>There's only one country on the continent with the word America in its name.

Not just the continent(s). The United States of America is the only country in the world with the word "America" in its name.

>I know the point is to reduce ambiguity between the U.S.A and Latin/North/Central/South America

This is only a thing in Spanish. In Portuguese, Americans (that is, those from and of the USA) are often called americanos. In French, américain is much more commonly used than États-Unien.

The Spanish meaning of americano that does not include Americans in this way is very unusual among major Western languages (<https://en.wikipedia.org/wiki/American_%28word%29#Other_lang...>). I don't mean to say that the equivalent of "American" in those languages is the only way to refer to those of the USA, or that equivalents to "USA" and such don't exist. In Portuguese, Italian, and German, however, saying Americano/Americano/Amerikanisch would generally be understood as referring to that of the USA without additional context, as opposed to a Brazilian or Argentinean, in a way that Americano wouldn't in Spanish.

Further, in Spanish the ambiguity is worse. "Los Estados Unidos" is another term for the US, despite the existence of Mexico (AKA United Mexican States / Estados Unidos Mexicanos). Norteamericano for "American" is also used, despite that term literally including those living in Canada, Mexico, and the Caribbean.

(Yes, I know that in practice, Spanish speakers understand that "Los Estados Unidos | EE. UU" and "Norteamericano" refers to the US and its residents. That's my point; shouldn't "Americans" also be understood in context that way?)

>but it still feels a bit condescending, like we're not even allowed to have a unique name anymore or even have a say in we should call ourselves/be called in our native language (and it doesn't help that the only time I hear "US Americans" is when someone is talking shit about us)

Correct; those who use it think that they are making a sly subtle dig against the warmongering imperialistic USAmericans.

The grandparent might just be German using a literal translation. In German, it is pretty common to call Americans "US-Amerikaner", even when we are not talking shit about you.

The shit-talking is by the way something you should not take too serious. I have seen it directed at Germany from smaller European countries as well. It is just natural to target the bigger, more powerful neighbour, especially when he behaves a bit too full of himself.

Just think of Don Draper answering to "I feeld bad for you!" with "I don't think about you at all."

> You really think that owner operators repair their own trucks? That doesn't make any economic sense. This is not a hobby, they need to drive to make money not to play truck repairman.

Oh yes! I have seen this unfold once in front of my own eyes, a real spectacle. Driver working for a driver company servicing a distribution company, tries to start the truck, something wrong with brakes, truck is driveable though, gets off, calls boss (company policy). One hour late boss finally arrives, gets in, unhooks trailer, parks the truck three meters to the side, gives the driver a different truck to take. 1 hour more paperwork to process, the trailer finally leaves the distribution warehouse 2.5 hours late. The driver company is apparently paying both late fees and parking fees to logistics company while this ordeal unfolds..

~4AM (5 hours later) a truck fixing mini-buss from a 3rd party truck fixing company arrives with two technicians. They plug into the truck, their diagnostics software shows nothing wrong, they leave.

Next day a different truck fixing company shows up and finally tows the truck after dancing around it for almost two hours with diagnostics software.

Quite a few thousands of pounds burned in just two days of people following rules and policies...

This is apparently "normal", this makes much "economic sense".

You don’t know what you’re talking about. 99% of the ride is on interstates. Much of that remote for that type of rig.

It’s the same reason Jeep’s use very simple mechanics. You can repair them yourself and carry appropriate spare parts.

I don't think your argument and analogy makes sense. Simplicity is not only valuable when an owner himself needs to repair the truck.

It's valuable when your truck breaks down in a middle of nowhere, and the closest official repair shop is hundreds of miles away, whereas there might be an "okay" level independent mechanic every 20 miles or less (the actual distance is not the point, the point is that an "okay" mechanic will be probably 10-50x more common).

Simplicity is also valuable with missing parts. Sure, the sophisticated solution is better in terms of performance, electronics, and whatnot, but it might take weeks to receive a part (even before COVID), because the shop doesn't have it and have to be ordered from China. Compare this with simple parts that you can again find in many old trucks and even smaller towns, making it much easier to replace.

Just to put it in coding analogy: if my business needs a website, or a landing page, I'm not going to hire a team of former Googlers and ask them to write a performant backend framework in Rust and invent a new frontend framework. I'm going to ask my uncle who is a hobby designer and can set me up a static site/WordPress in a day. I'm not trying to "justify poor engineering", I just prefer simplicity and the "poor engineering" approach gets my problem solved in one tenth of the time. Who is doing poor engineering now?

Also, coming back to the trucks. There don't need to be poor engineering from either side. Maybe the different requirements just caused trucks evolve in different directions?

Yep, owner operators repair their own trucks. Sometimes even fairly major engine work.

However, you can have well-engineered simplicity, too, and that seems to be rare. (As opposed to poorly engineered simplicity or highly engineered complexity.)

Actually, I think the irony is the other way around. I've read that worldwide, MB vehicles dominate many markets (e.g. African taxi and trucking) precisely because they are so easy to do local non-dealer maintainance on. Most of the world thinks of many MB vehicles as workhorses, not luxury or sophisticated vehicles.

Yes, MB deliberately cultivated a "luxury" brand image in the US and did not import very many of the "workhorse" models (the ones with smaller engines, manual transmissions, and few options) that the rest world knows.

I've often wondered about this. Here in North America we only get the Mercedes models that need their disc rotors replaced every 30k, and we see nothing of the indestructible and serviceable models that seem to wind up in places without posh MB dealerships.

I've always thought that this was because NA has air pollution laws that are strictly and honestly enforced and that that would make diesel cars difficult to offer.

>I've always thought that this was because NA has air pollution laws that are strictly and honestly enforced and that that would make diesel cars difficult to offer.

Yes, the US regulates NOx emissions much more than Europe. This makes it very hard to offer passenger diesel engines in the US. On the other hand, the EU regulates/taxes CO2 emissions, which the US does only indirectly through CAFE (fuel efficiency) regulations.

How is US fuel efficiency, though?

In Europe cars using 5 liters per 100 km (~48 miles per gallon for the SI-resistant amongst us) are very common.

Much worse than that. There may be a few non-hybrid models that can get that high, but they're very uncommon. You have to remember the best selling "car" in the US is a Ford F-150. They're also exempt from CAFE as I understand it, as they're classified as light trucks rather than cars.

This almost certainly has more to do with how low our gas tax is compared to almost every other developed country though, than any direct regulation.

CO2 emission is almost equal to fuel efficiency. So the regulation explain why.

MB trucks are an entirely different kettle of fish than the consumer and light transport stuff. It all changes above the 3500 kg mark.

In the US their Sprinters compare to the competition about the same way an S-class compares to a Camry. In both cases it's generally considered ill-advised to own it into old age.

I wouldn't call that "entirely different"

Sprinters routinely clock half a million K. You need to maintain them but that goes for all vehicles.

And they are still below that 3500 kg limit. It really starts at Atego:

https://www.mercedes-benz-trucks.com/nl_NL/models/atego-cons...

If the Sprinter took a comparable amount of maintenance to deliver the same service it would not have the reputation it does. It's not like people are jumping to conclusions based on brand either. It was initially branded as a Dodge or Freighter/Sterling. The only operators who like it are high end passenger fleets that depreciate them and then get new ones. Now, in its defense, people do generally hate the FWD Fiat van more...

I've seen some of this. People were bitching about their MBs not lasting long enough: turns out they were skimping on the oil, using regular oil rather than the synthetic oil those engines need. Synthetic oil is a lot more expensive but it lasts much longer. But America likes its oil changes, every ridiculously low number of miles because they believe that is what will make their cars last, rather than to use quality oil to begin with.

MB engines are indestructible if treated properly, they routinely outlast the body of the vehicles, they have oversized oil pumps, use chains rather than timing belts (a common failure point) and in general are designed to last.

There is plenty wrong with MB, their electronics absolutely suck and don't get me started on their software or their over priced parts. But their engines are solid.

There days Mercedes doesn't really export non-luxury vehicles to the US except for maybe sprinter vans.

That's not something a German engineer will easily understand, though :)

The noise level of some US trucks still surprises me. Jet engine like.

If it's when they are slowing down it's likely the jake-brakes j-brakes you are hearing especially if they have straight pipes. Diesel engines don't have engine braking by design so a mechanism was added to the heads to create artificial engine braking that can be toggled on per head.

[ Edit for clarification: ] I have created some confusion with this statement. For clarification diesel engines never had engine braking due to the lack of a throttle plate but this has been worked around with add-ons using different techniques. On a big-rig this is jake-brakes. On smaller modern vehicles this is usually a small turbo or an exhaust baffle. The operator of a modern diesel vehicle will effectively experience engine braking when they let off the throttle. On older diesel pickups and cars there was no engine braking.

>>Diesel engines don't have engine braking by design

First time I hear about this. I've driven and owned plenty of diesel vehicles in my life and diesel engines definitely do have engine braking(unless it's different in semis? but I don't see why it would be - just leave it in gear and let it slow down?)

The engine itself has no braking due to the lack of the variable air-intake that gasoline engines have that would otherwise starve the engine for air especially when downshifting and closing the throttle.

Specifically on non-big-rigs, modern diesel cars and pickups create engine braking using a small turbo and tighten the spline or in some cases have an exhaust feedback baffle or flap, varies with year/model. Big rigs still use jake-brakes.

Thanks! I learned something new today.

It doesn't have "no" braking. But it has a hell of a lot less than it would if there were some restriction on it, e.g. a throttle.

I've done what feels like engine braking in "consumer" diesel trucks. Since I never had to flip switches or anything, how does the engine know how to enter into this "engine braking" mode?

Never even crossed my mind that diesels don't natively engine brake. Then again how diesels work is a bit of a mystery to me... mostly because I never bothered to look into it much.

Newer diesel engines use a turbo or baffle. Most commonly a turbo to create effective braking. This is operationally superior to jake-brakes in that the mechanism is tied into the ECM and transmission allowing for things like cruise control to function as expected. Jake-brakes on the other hand require a bit of technique by the driver to use correctly and avoid jack-knifing the vehicle with its trailer, especially on ice. Some modern pickups can even be put into "towing mode" to make better use of the add-on braking mechanism and allow cruise control to work downhill.

I suppose this the right time for an important PSA. If anyone tows something heavy in an older diesel pickup be aware the only braking you have is what your brake pedal provides. Glaze those brakes and you are going on an exciting adventure.

For anyone wishing to experiment:

You can test the petrol-car-vacuum braking theory if you have an older manual petrol car with a cable from the accelerator to the butterfly valve of the throttle. While driving at 50kph, put into neutral, turn off the ignition, engage a lower gear, release clutch. Test pressing and releasing the accelerator pedal while using engine braking and feel for a difference.

SAFETY: 1. Don’t turn off the ignition all the way and lock the steering (although I admit that is very exciting to have steering locked into one direction, I don’t recommend trying it). 2. Be mentally prepared to lose power steering and power brakes. 3. Only on wide straight roads with no other traffic and safe ways to stop. 4. Probably other warnings specific to your vehicle, and situation. 5. I recommend against trying it on an automatic trans.

If your diesel has turbo vanes controlling the braking, you could probably test it out the same way (presuming electronics are disabled when ignition is off).

Another way to test things is to remove relevant fuses.

Disclaimer: there are lots of ways to screw up even being careful - I do not recommend learning by failure in deadly situations.

Diesels might have anti-shudder valve which closes air intake when shutting off ignition.

Interesting. I was only taught engine breaking from the practical perspective of down-shifting, but not the details of why it works. I understood the implicit effects of shifting down - maintaining the same high RPM with the same high resistance as a vehicle slows... but never gave much thought to what exactly those resistances were, I just assumed it was a combination of friction, compression, driving an alternator, other arbitrary mechanical losses etc.

Would there really be no significant braking effect without that "high manifold vacuum"? I suppose the engine does have a lot of mass so I could believe the effect could be too slow to be useful.

Gasoline engines have a throttle plate that, when you let off the throttle, prevents intake air from reaching the cylinders. The pistons try to draw air into the cylinders and create a pretty decent vacuum. (Respect to the throttle plate. :-))

Diesel engines don't; the throttle controls fuel flow into the cylinders. Let off the throttle and air flows through the intake, cylinders, and exhaust just without producing any power.

The effects of friction are roughly the same on both engines, and they are what engine designers and builders want to minimize to maximize fuel efficiency and power.

Technically diesel engines do not strictly "engine brake" because of lack of throttle plate, and thus lack of pumping losses. However that doesn't mean that it won't slow down: friction losses, heat loss to cylinder walls, etc. still occur. Surely diesel passenger car will decelerate stronger when left in gear than in neutral. Given how many pages and pages of discussions you can find people arguing whether petrol or diesel engines brake stronger, it seems pumping loss doesn't make that much difference.

Diesel engines do not have engine breaking? Are you sure? For me, engine breaking is just the fact that the engine, without power, have moving pieces which, by inertia, is going to slow down the vehicle. Diesel engine being heavier than "regular" engine, the engine brake effect is more important.

At least that's my experience with the cars I used to own.

Edit: For the record, my experience is for 4-strokes diesel engines. Apparently, 2-strokes are still in use in the US.

Diesel engines themselves have no engine braking. Each personal vehicle implementation of diesel engines have worked around this using different techniques. The most common outside of big-rigs is a turbo that tightens a spline or closes a feedback baffle.

To the operator of the vehicle it will appear there is engine braking on modern diesel engines. Older pickups and cars have no engine braking.

> Older pickups and cars have no engine braking.

So what did they do on long downhill mountain passes? Just ride the brakes? Were the brakes designed to accommodate being ridden for so long?

Asking 'cause I downshift all cars I drive when going down mountain passes...

They would drive slowly and carefully and take alternate routes when possible.

Just ride the brakes?

No that will overheat and glaze the brakes. That is why long steep hills initially had run-away ramps created. The run-away ramps are still used but not nearly as much as they used to be. In many places alternate routes were created for people towing heavy things. A good example of this is the grapevine on I-5 in southern California. There is a truck route and the main route. That also has many run-away ramps.

> In many places alternate routes were created for people towing heavy things.

That, uh, sounds pretty inconvenient!

So without engine brakes if you downshift in an older diesel does the engine just rev right up and the car doesn't even bother to act like it is slowing down? That has to be pretty weird....

It very much slows down. Just not quite as much as a gas engine. You still have friction losses (especially as you get higher rpm), losses from alternator, water pump, engine fans, oil pump, etc.

One of my vehicles is a VW Jetta TDI (diesel, ALH engine).

TDIs have turbos.

Eastbound on Interstate-40 on the eastern slope of the Appalachians the truck speed limit at the top of the pass is 35mph and there are very, very many warning signs including radar-activated lights. There are also three or four runaway-truck ramps (filled with loose gravel) that are somewhat frequently used, and often trucks pulled over to the side to let their brakes cool.

(The Rockies have even more of this sort of thing, but I haven't been out there in quite a while. :-( )

Diesel engines have no throttle plate that controls the airflow into the engine.

The closed throttle plate in a gasoline engine is what creates a gasoline engine's brake effect, by pulling a vacuum in the intake below the closed throttle plate, which produces the brake effect.

With no throttle plate, the remaining mechanical components in a diesel engine provide minimal friction, certainly not enough to produce any brake effect.

The jake brake (https://en.wikipedia.org/wiki/Jake_brake) converts the diesel engine into a huge air compressor when activated, which provides an engine brake effect. Unfortunately it also often creates a very distinctive, and often loud, sound from the exhaust as well.

> With no throttle plate, the remaining mechanical components in a diesel engine provide minimal friction, certainly not enough to produce any brake effect.

I'm not sure if maybe we have different definitions of "braking", but a diesel engine definitely slows down a car when one throttles down. The vehicle slows down faster than when on neutral, and the braking power depends on which gear is engaged, which seems to indicate very much that there is engine braking going on.

Posters point wasn't that the vehicles you drive didn't effectively have engine breaking, but that in diesel designs this is something that had to be added intentionally - with [edit gas engines] you get it whether you want it or not.

Fun fact - the effect can be strong enough on a high compression motorcycle engine to break your rear tire free (obviously lots of other parameters there).

Interesting.

But what do you mean by 4 cycles. The diesel engines I know all have 4 cycles. I though 2 cycles engines were found on old tractors from the 50s no?

Edit: Looking at [0], assuming this is true, I understand the confusion now. It seems, in the US, heavy duty diesel engines are 2 strokes which, apparently, do not have engine braking.

Me being sloppy, of course you can have 2-stroke or 4-stroke diesels. Edited to improve.

The main thing going on here isn't the cycles, it's the lack of a throttle plate. With these designs the amount of air entering cylinder doesn't relate to your throttle position.

If you come off the throttle every compression cycle a "full" cylinder of new air gets compressed, then decompresses and pushes against the piston. In normal operation the energy is re-transferred to the crank (with some loss). It sort of "bounces". But with a compression brake, you force the engine to do the work of compressing that air, but then full open the exhaust valve to let the pressure escape... much more energy lost each cycle, which transfers through drive train and slows you down.

In comparison to typical ICE: in that case when you come off the throttle, the intake is sealed off, so the cylinder on intake stroke is "sucking" against a closed path, which loses energy. Similar effect, different cause.

In a 4-stroke engine, throttle or not, intake valves are shut down when in compression so cylinders are sealed off, compression happens anyway, diesel or gas. Indeed, in 2-cycles engines there are not intake valve so LinuxBender's point is valid.

I think you misread; I should have been clearer. This is how I understand/remember it although to be fair it's been a while since I've worked on either so might mess it up a bit.

Anyway it has nothing to do with compression or the intake valve in either case. Compression happens in both cases, and doesn't affect anything.

In diesel, Jake type breaks steal energy by opening the exhaust valve right after TDC, e.g. what would be the power stroke. The energy stored in compressed air escapes out the exhaust valve rather than being (mostly) reclaimed by the crank on expansion - this slows down the crank and hence (if not in neutral) the vehicle slows. NB this is not when the exhaust valve would normally open, but rather a cycle earlier.

In gas, on the intake stroke the intake is blocked (not by the valve, further up by throttle) so the intake motion creates vaccuum - this takes energy, which slows down the crank, and hence etc. etc. The exhaust valve doesn't change timing.

The latter approach only works if you have something blocking the intake "above" the intake valve. In a diesel engine the airflow is kept the same and the fuel adjusted (unlike gas) so there is no natural mechanism to do this with the throttle.

Most of the energy stored in the cylinder charge during the compression stroke is returned (as if an air spring) on the (what would be the) power stroke. The difference between a gas and diesel engine shows up in the higher pumping losses on the intake stroke (if you're pulling air past a closed throttle plate or not).

Diesel engines might not have throttle plate but they use injection which certainly do not inject air when acceleration is released, so the cylinders will act exactly the same way. Reading the web I see conflicting account on this subject. Strange...

Also, I though that modern petrol engines did not have throttle plates anymore and use the same injection system than diesel engines (no more carburetors).

The fuel system doesn't provide restriction on the air going through the engine.

A diesel engine that's not dumping in fuel (because your foot isn't on the pedal) has about as much engine braking as a gas engine that's run out of fuel but the operator has floored the pedal.

A gas engine has a throttle that can restrict airflow. A diesel can either be equipped with an exhaust brake or compression brake. The latter is tons more effective but louder.

> use injection which certainly do not inject air when acceleration is released,

FWIW injectors don't inject air; the airflow is separate, get's compressed (and hence heated) then the fuel is injected, then bang (in diesel)

>work the same way as 4cyl

I'm not sure what you mean, both Otto and Diesel cycles are four-stroke.

In petrol engines power is usually controlled by throttle plate which limits volume of air going into cylinder, and enough fuel is added during the intake stroke (either by injection or carburetor) to have combustion close to stoichiometric.

In diesel engines there's no throttle plate and engine always runs on lean mixture, and power is controlled only by amount of injected fuel, which is done after air is already compressed and hot.

Point was injectors inject fuel not air...

I think we cross-edited, remaining confusion I think was about 2 vs 4 stroke but it's not really relevant so I had adjusted with a nod to when diesel injection occurs in 4.

> With no throttle plate, the remaining mechanical components in a diesel engine provide minimal friction, certainly not enough to produce any brake effect.

I don't understand. I've driven multiple diesel engine cars throughout the years, and they most definitely have a brake effect. I'm not even sure they brake less than the gasoline cars I've driven. Easily enough to slow down for taking an exit from the freeway, for example, when shifting down appropriately. To the point that there regularly are situations when I lightly press the brake pedal not to brake but to simply light the brake lights, if there are cars behind me.

It does sound plausible that the lack of a throttle leads to less or no brake effect, but it simply doesn't fit my observations.

I'm talking about regular cars here, both recent and less recent (the oldest one was built in 1989).

Maybe there are different diesel engine types with different brake capabilities? Or do some gasoline engines brake much more than what I'm used to, and my reference for what is and isn't significant braking is all wrong?

See @ska's comment at https://news.ycombinator.com/item?id=30195348

https://www.youtube.com/watch?v=o8Cta2cC2Co

https://en.wikipedia.org/wiki/Engine_braking#Diesel_engines

There's nowhere near enough inertia in the rotating assembly of an engine to significantly slow down a vehicle.

It's not the inertia that does the job (that keeps things going, actually) but the compression and shedding the compressed air that will slow things down. But for a big rig doing that idling it won't be enough, especially not on a descent with 25 tons pushing you downhill.

It's also the friction of everything turning. And you've still got your alternator, oil pump, water pump, fan etc that are removing energy.

A Jake Brake is essentially using the engine as a compressor and then venting the air at TDP, that's why they make such a racket.

A Jake brake is for long descents, it essentially uses the engine to slow down instead of the brakes to avoid overheating them.

Normal diesels do engine braking just fine, but not aggressive enough to shed speed on a long descent without over-revving, and you really don't want to do that with a diesel engine.

Extra crap = extra weight. Extra crap = extra complexity = extra maintenance costs. "Sophistication" does not always equal better!

More macho - what a laugh! Keep it stupid simple.

But also extra effort from the driver = more tired driver, higher chance of accident, more mistakes and issues with every delivery.

I have not driven a truck like that personally, but I know what sort of difference all the modern assistance systems have done on my cross-continental drives. Previously a 12 hour drive would leave me absolutely exhausted, like I'd need a full day to recover after that - in a modern car with lane assist and adaptive cruise and comfortable seats and what not - I arrive relaxed every time. Long dull stretches of road don't take such a mental toll anymore.

I imagine the exact same principle applies to trucks.

In my 30s and 40's I could drive 14-16hrs a day without a problem, in a stick-shift car, in the USA. In my 50s, 10hrs is still reasonably OK.

However, a 4 or 5 hour drive on roads in the UK in an automatic modern car and I am completely exhausted.

At least for some of us, the road conditions are a far larger impact than the features of the vehicle.

Absolutely! We visited family in Italy last summer, and had an all-day drive. Just constant attention and input, compared to cruising along some 2 lane road in the US. Cars coming up behind you, whizzing by you. A slow old car up ahead. Big truck to pass. Tight curve. Road narrows. Road widens. Some dude in a BMW riding your bumper. For like 8 hours... I was so glad to get out of the car. If it hadn't been for the pandemic, I would have much rather taken a train and relaxed.

Yeah....that 12 hour drive I mentioned includes driving across the entire width of Germany and jesus it is stressful. Yes, the unlimited sections are "fun" and it's really cool to be able to drive at 150mph+ for a while when the conditions allow, but it also means you need to be on like 10x the alertness level as normal. Like really really really pay attention a lot at all times. It can be super harsh. But the last few times I'd just set the cruise control to something more sensible and just relax, with the modern systems the car basically drives itself.

It's really easy to spin a naive fanboy (of a particular brand, technology or otherwise) narrative like this and when you aim your tropes ("ze backwards yankees") right at audience's bias you're sure to get a bunch of virtue points in response.

The fact of the matter is that there's very, very, few secrets in the automotive and heavy equipment industries. If someone is or isn't doing something it's because they've run the numbers and they don't think it pencils out for what they build and who they sell to.

It's really easy to spin a naive fanboy narrative like this and when you aim your tropes right at audience's bias you're sure to get a bunch of virtue points in response.

That's one of the big problems with internet blogs. They do a bunch of Googling and speculation and that's it. Laughably, they sometimes they even call themselves "journalists."

How hard would it have been to go to a truck stop and sit at the counter and ask some truckers? They know all about trucks. And after being along all day, truckers love to talk.

If you're afraid of people, get a $10 CB radio from Goodwill and talk to them on the radio.

Yeah, but those people are perhaps the worst to get insight on the industry from. For instance, most truck drivers in the US haven't driven a Scania truck (and flipped for the EU). They can't give you comparative information, so everyone's natural tendency to defend their choice will give you a bunch of rationalizations that you can falsely assume to be reasons.

It's the same as how you could ask people why SF doesn't have gigabit fiber Internet for $60 when Bucharest does for $30, and people on the Internet will make up all sorts of reasons. However, SF does have gigabit fiber Internet. Explaining is easy. Truth-seeking is hard.

Historically, Freightliner’s reputation was for driving fast…and you would be prudent to get out of the way when one was coming into the mirrors.

Speed perhaps explains the lack of power steering. In multiple ways.

What does speed have to do with power steering?

Geeze. You have to go all the way to the bottom to find the answer.

"Maximum length of a truck with a semi-trailer in Europe is 18.75 meters. Some countries have some exceptions, but generally that is the rule. In order to use the maximum of this length for the cargo the tractor unit has to be as short as possible. The best way to achieve that is to mount the cabin over the engine."

Cab-overs have no other advantages, and everything else the article talks about is a side-effect of the length limit.

The funny part is when you go to the 4th photo down and look into the passenger-side window. Got to wonder whether the author did that on purpose, or didn't notice.

> Cab-overs have no other advantages

That's not true. Lower overall length is an advantage for maneuvering in city streets and parking lots, which is why you see medium duty COE vehicles (mostly trucks but semi-tractors as well) in some parts of the US making local deliveries. It also provides a visibility advantage that reduces the accident rate.

However the US still has relatively huge trucks delivering and navigating our urban environments that have many pedestrians and bicyclists.

It's really frustrating how the US has too many urban streets designed for accommodating oversized trucks. It's really dangerous because the side affect of accommodating huge trucks is high speeds of passenger vehicles.

https://nacto.org/publication/urban-street-design-guide/desi...

> Cab-overs have no other advantages, and everything else the article talks about is a side-effect of the length limit.

There are definitely other advantages, such as that cabovers can generally navigate into tighter spots because of it's tighter turning radius. Yard space is usually very limited and roads more narrow and windy than America, so this is definitely a benefit.

I've seen some crazy tight turns on some unreasonably tiny country roads here in the UK that I can't imagine could be done with a vehicle 2 meters longer.

Almost every other episode of Grand Designs has some smart lorry driver reversing down a tiny access road.

I'm surprised the article doesn't mention ferries. Many routes in Europe can involve sea transport, particularly UK-Europe, UK-Ireland, Denmark-Norway/Sweden, to islands like Scisily, Corsica and Sardinia. This gives the compactness of the cab-over design a big advantage here.

Often the cabs don't go on the ferries. They drop the trailer at the dock, a separate crew driving yard tractors loads the trailers onto the ferry, and they get unloaded on the other side, where another cab picks them up to continue. This can be more efficient as you don't need space on the ferries for the cabs, and you don't have dozens of drivers waiting around for the ferry to arrive. The yard drivers at the dock are very skilled at quickly getting the trailers on and off the boat, while road drivers would take a lot more time with these manouvers.

This is true for a lot of goods, but if you go on passenger ferries you'll still see tons of commercial trucks streaming in and out of the port. For time sensitive deliveries, like perishable goods, they often need to avoid the delays from handling containers. If anyone remembers Norbert Dentresangle, an iconic french transport company that got re-flagged a few years ago, you'd see their trucks streaming in and out of Dover and on UK motorways all the time.

What I find surprising is how the majority of semis in Netherlands appear to be very new and presumably in good condition. In Texas, by contrast, few appear to be new and well maintained, while many look quite heavily used. The trailers are even worse.

Considering how expensive those things are, who is affording the new trucks in NL? Is it because they are company owned instead of individual (owner-operator)?

Where do the worn out NL semis go?

You will find that wildly varies in the US too. For example Walmart has very nice trucks. But some random LTL probably has used equipment that is decades old. It comes down to the fact that most of this has a very thin margin. Large private company fleets tend to be newer. Small general delivery tend to be older.

and all of the owner/operators who specifically want pre year 2000 rigs so they don't have to have an ELD.

> Where do the worn out NL semis go?

African countries

> Where do the worn out NL semis go?

Eastern Europe, if I had to guess. I can't say specifically about semis, but in my home country of Romania I've seen quite a lot of Dutch clunker vans/small trucks roaming the streets (you can tell they're Dutch because they still have some of the original branding decals of the companies that used to own them).

Same with German vehicles. When they fail inspection (usually because of emissions), they are sold to other countries. Central Asia is full of trucks with German lettering. It's always interesting to see.

The US has a similar dynamic:

https://en.wikipedia.org/wiki/Vehicle_inspection_in_the_Unit...

I work for a private ambulance company in the US that shifts ambulances between states based off of emissions requirements. Crews working in California for example will always get the shiny new ambulances, while those in Kentucky get ambos with 200k miles (slight exaggeration) to replace the ones that have been driven into the ground.

If they are just sold on and continue to be used when they fail emissions testing, what is the point of emissions testing at all? The vehicles will just end up in countries that don't care, and emissions will rapidly get worse as they will get minimal maintenance and probably lower quality fuel.

Something similar happens to "recycling" as well, take for example: https://www.youtube.com/watch?v=mFjsL61qi3g

If there was no emissions testing to begin with, these trucks would be designed to pollute for their entire service life, instead of just the last 20-40% of it.

Also, I don't want pollution in my town. The tradeoff of 'tiny reduction in cost of transportation for way more air pollution' is not worth it for me.

If some other town on the other side of the planet thinks that trade-off is worth it, that's their decision to make. The effect of this kind of pollution, unlike GHG emissions, is largely localized.

Mainly because we are talking about NOx and other Health related emmissions that have local effects not CO2 that have global effects. Yes it sucks about the countries where they end up but it's the responability of the local governments to care what level is acceptable and what not. And often governments have to balance the need to stimulate local economy (by affording to buy cheaper used machines) vs the public health concerns.

It sells new cars, and helps countries look like they care about the environment. The problems get dumped onto other countries.

Perhaps someone can provide a more charitable view, but that's my understanding.

When I was travelling through Ghana I saw tons of cargo vans with Dutch and German decals, advertising plumbers, bakeries, delivery services, etc. It was a bit odd to see them in the middle of West-Africa.

I'm actually kind of curious if anyone ever made a documentary or something about the trip those vans and trucks make, feels like a hidden economy.

It depends on the carrier in the US.

Lots of carries take good care of their equipment.

You can also be a carrier and just be one guy and a truck … so there is a lot of variety.

Older trucks dont have the same emissions requirements and are sought after big time in the US.

>Where do the worn out NL semis go?

Eastern Europe. You need to have a Euro 5 or Euro 6 diesel engine to be allowed in many Western European cities as a commercial truck. So old trucks aren't viable.

Some jurisdictions have limits on how old trucks can be, or increased inspection frequency based on the age of the vehicle. Some businesses/terminals have restrictions on the age of equipment too, for instance the port of Vancouver is about to ban trucks older than 10 years. I believe regulations in TX are very lax compared to other parts of the world.

> In Texas, by contrast, few appear to be new and well maintained, while many look quite heavily used.

That is pretty interesting. A few weeks ago, there was a thread here on HN talking about the Port of Long Beach backlog and a comment mentioning the scarcity of trucks with the clean idle certification.

At about the same time, I took a road trip along the Interstate - Illinois, Indiana, Ohio - and paid attention to the trucks. Somewhere around 90% of them had the "California Clean Idle" sticker on them - and none of them had California plates. Even on trucks with Ontario plates (you see a lot of Canadian trucks in the upper midwest).

My best explanation is that the long-haul routes crisscrossing North America have all the newest, cleanest, most modern vehicles and once they reach a certain age they are sold into the places where they don't drive long distances anymore.

As well as the other responses, it is very common to lease your fleet in Europe, particularly for 3PL's who will lease the fleet over the duration of their contracts.

Most transport is done by 3PL's who will lease the trucks and hire the drivers.

It's definitely primarily because of the space on the streets. I would not want to try to maneuver a American Semi through Europe.

The article states that it's because of length restrictions. European leangth restrictions include the truck, American restrictions don't.

Presumably, though, the length restrictions are due, at least in large part, to [lack of] available space on the streets.

The European length restrictions don't exist because someone hates long trucks but because city and road planers don't need to account for longer trucks than that. This is especially important because of parking. In the EU there are maximum driving hours for truckers which means they often need to take rests and the infrastructure needs to support that.

> In the EU there are maximum driving hours for truckers which means they often need to take rests and the infrastructure needs to support that.

The same is true in the USA.

Specifically:

    - 14 hour days, maximum
    - high tolerance of pulled over "resting" trucks
    - conventional truck designs with builtin bedrooms
    - state-run and private truck stops along most highways

In EU (for comparison):

https://www.gov.uk/drivers-hours/eu-rules

The tachograph [0] is - I believe - not used (not mandated by Law) in the US, though it is being introduced recently.

[0] https://en.wikipedia.org/wiki/Tachograph

The US equivalent is the ELD [0], which basically does the same thing with minor technical differences. They've been mandated for years. I'm not a truck expert though.

[0] https://en.wikipedia.org/wiki/Electronic_logging_device

That and the fact that European truck drivers don’t live in their trucks on a semi permanent basis.

> One of the differences between European and American trucking is that owners-operators are very common in US and not so much in Europe. These people own their own trucks and pretty much live in them for months at a time. Semi-trucks with conventional cabs feature longer wheel base, which makes them a little more comfortable. Also, they tend to have a lot of room inside. Owners modify their trucks to include huge living compartments – something not common in Europe.

I wonder why owner-operator truck drivers are more common in USA than Europe? Is it an externality of our lack of worker protections and safety net?

I'd guess that in Europe there are a lot less long-haul drives than in the USA. Those are the ones that can pay big bucks and make O/O efficient. If you're going on a 6 hour round trip there's no reason you can't drop off the truck at HQ and head home to your family.

Europe also kept maintaining their rail lines whereas the US has neglected ours because trucks were seen as a way to stick it to the rail companies. Our loss considering that freight trains are 4 times as efficient in terms of cargo ton-miles per gallon of diesel.

The US makes extensive use of freight rail. Like look at the per Capita number at the end of https://en.m.wikipedia.org/wiki/List_of_countries_by_rail_us...

The modal share for rail is also relatively high.

A lot of it is bulk commodities of course.

It just seems like for the quantity of stuff we move around, we should have more rail. We have massive wide open flat spaces to build rail lines, yet, we don't.

Transport by car or truck accounts for 20% of US carbon emissions, while freight rail is just 0.5%, and the freight rail is moving 28% of all cargo "ton-miles".

Rail doesn’t get things to the last mile and can be slow. Efficient in volume not in time.

America’s freight infrastructure is the envy of many country. It isn’t modern,fast, or even that well maintained, but it is extensive. Passenger rail is a completely different story in the US.

I’m guessing you’ve never looked at US rail in any aspect other than passenger rail? The US runs ~8x the rail freight that the EU does.

My kneejerk reaction would be the higher rural/urban ratio, but I don't think that's right, becaues Russia has even more rural space.

It's probably more due to the fact that many of the roads in the USA were built a lot more recently, and were built to make it convenient to use larger tractor-trailers (and not so much for other road users). In Europe, truck operators had to fit into the existing road system.

America has large cities scattered across the entire country. When I look at a map of the cities in Russia, the majority are in the far west and south with huge amounts of the country without any large cities.

The US Interstate system is extensive, well maintained, and fast. 60-80 mph will be the average speed for a truck on these roads.

If you are a long haul trucker you spend 95 percent of your time on these roads. You want high speed stability that a longer wheel base provides and don’t care too much about tight menuevering, because you probably don’t have too much tight area navigating to do. You will drop at a large warehouse on the outskirts of a city that was built for trucks like the one you are driving and be back on the road to the next warehouse.

Truck drivers often drive many thousands of kilometers on a haul, and I don’t mean in a loop. They might have a job to drive from LA to Memphis (almost 3000 kilometers), then they will pick up a load in Memphis and drive it to Miami. It might be many months before they are back in the LA area. Cheaper to sleep in the truck than in a hotel. Plus, time is money. Pull off the road, sleep for 8 hours, wake up and hop back on the road immediately.

It's not all that different in Europe. I think most drivers get home around once a month or so, so more frequently than in the US. But while on the road, they also sleep in their trucks.

I was interested in knowing the price of trucks and did some research:

The Volvo VNL 2021 costs around 174.000$

That's the new model shown in the youtube video in the article: https://www.youtube.com/watch?v=9nY7Xfu47vw&feature=emb_logo

Given semi-trucks are so expensive and heavely used I wonder why more companies don't focus autonomous vehicles for semi-trucks rather than robotaxis.

Or rail, which is vastly more efficient than trucks (which then could be used only for last-mile)

The US has more rail than any other country in the world. [1]

[1] https://en.m.wikipedia.org/wiki/List_of_countries_by_rail_tr...

miles of track per square mile, or alternatively, miles of track per square mile of population above N-per-unit-area would be a much more meaningful statistic.

I'm not sure population is too important here, that stat would just make dense countries look 'better'. In reality if you want to ship something from California to DC by Rail, it really doesn't matter that 95% of those 3000 miles have almost no one living nearby.

We're talking about Semi Trucks here, so clearly this conversation is in regards to cargo.

Hence my second proposed statistic.

"3000 miles of track to service land holding 60 million people" vs. "100,000 miles of track to service land holding 50 million people".

(the numbers are invented, not real)

Hence my first proposed comment, "that stat would just make dense countries look 'better'".

The U.S has a lot of empty land, so this would just be a manufactured stat with arguable meaning.

No, it wouldn't because the only land that would "count" would have more than N people per square mile. So in the US, North Dakota would barely count for anything.

Europe has rail. Does anyone know if they use fewer trucks than in the US?

US uses more rail than Europe for cargo (and the opposite is true for passengers).

Yeah, I don’t think people really grok that. They think “US hates rail, Europe loves it,” but this only applies to passenger travel and for freight, it’s flipped.

Maybe part of the reason the US has less passenger rail is because freight rail is prioritized and we use airplanes and automobiles instead due to the vast distances between many of the population centers and the lower overall population density (a given random two geographic locations will have fewer people moving between them and therefore will be tougher to justify passenger rail). Also, sea transport between different coasts of Europe is a little easier than between East and West Coast in the US because you don’t need to go through the Panama Canal. Then again, the US does have a very good inter coastal waterway and good navigable rivers both via the Mississippi and through the Great Lakes (thanks, Canada!).

I'm not sure we do (whatever we normalize by to compare the 2 big areas), freight trains are not big in Europe, because of size. Our most populous and wealthy countries are next to each other. For trains, you need to amortize the cost of loading/unloading.

basically if it's worth it to put it on slow transportation "coast to coast" we have a single continuous boat path between the North Sea and the Mediterranean Sea, whereas the US does have to think twice when sending a ton of things from LA to Texas, it's either train or Panama Canal.

Rail is rarely used for freight in smaller countries, because you have to move it to trucks anyway to get it moved the last 0 - 200km anyway. So if the country is only 400km wide, you’re wasting to much time load and unloading.

This but also the _first_ 0-200 km. Many manufacturers (especially small and medium size) are located far away from major rail networks.

The cost of the vehicle is irrelevant for autonomy, what's important is the cost of the driver. And for a freight train a mile long, that is pretty negligable. For a taxi carrying one passenger, not so much.

maybe because its easier to persuade car owner to buy self-driving car.

The better question is why are Russian trucks and their drivers so different: https://www.youtube.com/watch?v=4_OcK0P9WOs

So Optimus Prime was more the European style

Cab-over trucks were more common in the US in the past.

Cab-over trucks were more common in the US in the past.

I remember this, too. I had toy trucks when I was a kid and they were all the snub-nose design.

Interestingly, school buses seem to have gone the opposite way. When I was a kid, they had the long nose, but now most that I see are snub-nosed.

Does anyone know the term for those little "hopper" trucks that are used at ports and large post offices and such? The ones where the cab of the tractor trailer only exists on the left or right side of the tractor? I've heard that since they don't travel on public roads that they aren't subjected to environmental or safety rules.

Yard tractors or terminal tractors. Sometimes called "yard dogs"

Check out the series "Long Way Round" if you have access. It has a Kamaz -- impressive to see the rivers it can cross.

https://bestride.com/news/the-kamaz-that-saved-ewan-mcgregor...

I've often wondered why European trucks don't have some sort of mechanism to make them more aerodynamic when they're on the highways i.e. an inflatable nose.

The boxy design must cost a fortune in fuel

You have often wondered why trucks do not come with inflatable noses?

yes

From my understanding, the drag caused by the flat back of the trailer causing a vacuum is much more impactful than the front shape. I believe a "pillow" of air kind of builds up in the front.

It also looks like truck in EU are limited to 55mph. When I tow our trailer (just with a normal vehicle), there's minimal difference between fuel economy between 45 and 60. Significant drops come into play at higher speeds.

Drag is proportional to the square of speed

Ah. Yes! I forget about this!

In vehicles, there's a lot of additional, interesting factors at play - like engine efficiency.

Yes there will be many nonlinear factors which combine to a maximum efficiency speed, which can, to an extent, be chosen by design.

From my understanding, the drag caused by the flat back of the trailer causing a vacuum is much more impactful than the front shape. I believe a "pillow" of air kind of builds up in the front.

A lot of long-distance American tractor trailers deploy fold-out cones on their back doors to improve their aerodynamics while driving. They fold up for low speed driving and loading.

Also, fold-out flaps under the trailer for the same reason.

I've always wondered the reasons behind the regional difference in popularity of these. Trucks in the middle of the country seem to have them, trucks on the coasts seem to not. And you'd think longer haul trucks would be the most likely to have them, and so you'd end up seeing some on the coasts regardless.

Is it something with state by state safety regulations, like prohibitions on protruding structures that aren't part of the main body? Or differently-defined overall length restrictions? Does a given long haul truck have them deployed in the middle of the country, but then they're removed before getting to the coastal states?

> I've always wondered the reasons behind the regional difference in popularity of these.

There's an interesting mis-alignment of incentives. It comes down to who owns the truck vs the trailer.

* Truck owner pays for fuel.

* Trailer owner pays for the flaps.

So, unless you own both the truck and trailer, there's little incentive for trailer owners to install them.

That by itself isn't enough to explain the stark discrepancy though. Surely in the regions where tail flaps are extremely rare, there are still some operators that own both trucks and trailers.

In terms of aerodynamics, a blunt nose isn't actually that bad - the real drag is caused by flow separation at the rear of the vehicle. It's far more important to have a gently tapered tail, to avoid a stagnant low pressure zone forming.

Think a typical "teardrop" airfoil shape, they are blunt at the front and gently taper off at the rear.

In fact most cars are more aerodynamic in reverse than they are going forwards for exactly this reason - on most cars the front end comes in more gradually (the hood portion comes in first, then enlarges to the passenger section) whereas the rear end is usually much blunter (to maximize storage space).

Ok wow, that last point really fascinated me:

> most cars are more aerodynamic in reverse than they are going forwards

I tried to find more about it, but I could only find two sources. The first was a Mythbusters episode about a particular Porsche, and the second was a Top Gear episode about a different car. Can you point me to an article that substantiates this?

https://en.wikipedia.org/wiki/Kammback

https://en.wikipedia.org/wiki/Drag_coefficient

He's BSing or just ill informed.

If you taper properly before the flat cutoff a squared off back (Honda insight is the quintessential example) is fine because the real turbulence happens a few feet behind the vehicle. At speed a blunt (even if it's rounded) nose just isn't great no matter how you cut it but with careful attention to corners, shape transitions and whatnot you can mitigate that quite a lot (modern crossovers with their bulbous front bodywork make heavy use of this).

This is a subject with a million gotcha's that add up to a lot. Be weary of anyone peddling rule of thumb solutions.

Okay, perhaps I over-generalized somewhat. If one was to exclude the little details and edges, intended to optimize the airflow in the forwards direction, I contend that most cars would be more aerodynamic in reverse due to their general shape.

Here's one data point, merely removing the rear spoiler an SUV has the same drag in reverse as it does going forwards: https://airshaper.com/blog/mercedes-eqc-drag-coefficient

If the same car had the fine details massaged for the reverse direction in a similar way to how they had already been done for going forwards (i.e. instead of the rear spoiler, putting a similar spoiler facing the opposite direction at the front of the car), the Cd would be significantly less in reverse.

I drove an early Honda Insight with and without the rear wheel baffles; it was really interesting how you could feel the difference in the drag. Little car had hands on its hips holding it back, without the skirts.

I'd love to get it running again but cant find decent instructions for swapping the battery system out for a normal alternator and battery.

I've heard multiple times that people will put themselves behind trucks while driving on the highway and consume only half of the gas they would have used if they weren't behind them. It's probably related to that.

I remember seeing either Mythbusters or TopGear episode where they tested this.

It was a Mythbusters episode, and they concluded that you needed to be following the truck extremely closely (I believe within a couple of feet) to see a gain in fuel efficiency. The driver was unable to keep that small distance consistent for a continuous period of time causing more speed variations, resulting in a loss of fuel efficiency.

It could also be because trucks drive efficiently with little speed variations, at speeds of high fuel efficiency, 80-90 km/h. Drag is actually much more complicated than that, the air being is turbulent.

May be a little, but classic hypermiling technique is to do that anyway. So the slipstream gains are real since absent the truck a hypermiler is going to do the same thing anyway. I never hit the heady heights of good hypermilers, but I had a car I could reliably do 23 km/l, 55 mpg in.

Funny, my current car does 24 mpg on the highway at the speeds I like. Half the efficiency and probably mostly due to me.

Semi under 12 tons can go up to 110km/h in France, and I think most of them drive around that speed.

It's called slipstream I believe.

Hypermilers do this - pretty fun / a bit dangerous.

Bikers do this too BTW if you follow the sport, makes for interesting team type tactics.

There is some thought that automated road convoys of trucks following closely might generate fuel savings this way as well.

Cyclists ("bikers" is an ambiguous term) enjoy a 30% reduction in required power output to move at typical race speeds when within a reasonable size peloton compared to riding out on their own.

That's mostly untrue

Here's a study which pretty much confirms my idea of slightly rounding off the nose would be the best thing https://www.transportenvironment.org/wp-content/uploads/2021...

Image here: https://ibb.co/FgZvz6p

From your article: "fuel savings of 3.2 to 5.3%" from rounding of the front

The article itself states there are bigger benefits to be had modifying the trailer:

"Further aerodynamic improvements are possible, notably on the trailer. For example aerodynamic add-ons, such as tails and side wings, could help deliver even higher significant fuel savings. Their potential is explored in another T&E briefing. [23]"

The referenced article: https://www.transportenvironment.org/wp-content/uploads/2021...

That article shows a variety of tail modifications which have higher effectiveness than rounding the front.

Trucks are allowed to be a bit longer now (0.5m iirc), but only for aerodynamic measures. The first few trucks taking advantage of the new rules are on the road now, but it'll take a while before fleets have been replaced.

The most effective aerodynamic changes are on the back though.

A blunt front isn't that bad for aerodynamics as long as it's rounded enough for the air stream not to separate. A lot more can be gained at the back of a truck. Like this: http://learntoflyblog.com/wp-content/uploads/2016/04/4-5.png

European trucks seem to generally have better fuel economy, but this might simply be because fuel economy isn't a focus of US manufacturers.

It does, but the key heare is the length limitation. Spending 1m on a more aerodynamic shape means 1m less cargo space. So the fuel efficiency per cargo volume actually goes down.

Actually having a smooth undercarriage and a smooth transition from truck to trailer and some wind breaking fins reduce drag a lot.

https://en.vda.de/dam/vda/publications/FAT-SCHRIFTENREIHE%20...

And the front aerodynamics dépend more on the details than it's length. Some aerodynamic designs have shockingly steep fronts.

https://en.m.wikipedia.org/wiki/Schl%C3%B6rwagen

Ugh, one of those articles that paraphrases its title 5 times before giving a very short answer...

How can I make a 300 word article into an 800 word article?

Actually, I think I just saw a GPT-3 application that allowed you to "lengthen" text.

> Actually, I think I just saw a GPT-3 application that allowed you to "lengthen" text.

And a browser extension that shrinks it. And the AI wars continue.

Do European trucks make less noise too?

I'm from Spain but moved to Mexico 13 years ago. Here it's somewhat common to hear truck noises like when doing engine braking. I don't recall ever hearing that in Spain.

Maybe automatic vs manual gearboxes?

As far as I'm aware, in the mexican transport industry is a common practice to overload the trucks as much as possible.

This is so widespread that any company which doesn't do it is likely less profitable than all the rest which do overload hence they have to overload to be competitive.

I like to frame this in terms of an overruling pragmatism in mexican culture, as long as the truck still goes everything is just fine.

I suppose overloaded trucks (under more stress) are louder.

It would be interesting to factor in the higher maintenance costs, including road maintenance.

Europe has strict noise regulations that even regular trucks have a hard time meeting, much less a jake brake [1]. In the US these are no problem since such large swaths of the country are unpopulated, but here in Europe you got small villages next to highways all the time.

Here, the more expensive hydraulic retarders are the most common brakes (additional to the standard brakes on the wheels, of course).

[1]: https://www.verkehrsrundschau.de/nachrichten/nfz-fuhrpark/ne...

Do truck in Europe even use jake brake? I cannot remember I've ever heard one, while in few days in the USA/CA I've heard one every single day on highway

It isn't even allowed to put jake brakes on trucks here, the model would not be certified as the noise emission limits have to be adhered at all times during the operation of the vehicle.

Is that true, or just unmuffled jake brakes? It's pretty common in the US for unmuffled jake brakes to be prohibited in populated areas.

Another source on the "Jake brake" https://en.wikipedia.org/wiki/Compression_release_engine_bra...

And to quote the important part:

"Most diesel engines do not have a throttle body, so regardless of throttle setting a full charge of air is always drawn into the cylinders (excluding the valve fitted to certain diesels, such as fire appliances and generators on oil and gas platforms, to prevent diesel engine runaway). Compressed air generated during the compression stroke acts as an air spring to push the piston back down. As such, even with fuel supply cut off and no power strokes taking place, a portion of the energy absorbed by the compression stroke within each cylinder is returned to the crankshaft. This results in very little engine braking being applied to the vehicle.

The typical compression brake consists of a hydraulic system using engine oil which transfers the motion of the fuel injector rocker arm to the engine's exhaust valve(s). When activated, the exhaust valve opens very briefly near the engine's top dead center, and releases the compressed air in the cylinder so that the energy is not returned to the crankshaft. If used properly, a compression release brake can assist a vehicle to maintain or even reduce speed with minimal use of the service brakes. The power of this type can be around the same as the engine power."

Basically, jake brakes vent the compressed air in the cylinders at the top of the cycle.

Most (many?) US municipalities prohibit the use of engine braking within their boundaries.

Unmuffled jake brakes, as far as I have ever seen. You can still use one as long as it's muffled.

1) https://www.google.com/search?q=no+engine+brake+sign+USA&tbm...

2) https://www.quora.com/Do-no-engine-brakes-signs-apply-to-muf...

Most of the time engine braking is banned within US city limits, there are signs posted outside of towns "No engine braking".

It varies by region, I'm sure, but every sign I've ever seen prohibiting engine braking has been specific that only unmuffled engine braking is prohibited.

No they aren't allowed whether they are muffled or not if it says "no engine breaking".

Seems like Mexicans are not punished for taking off the muffler or generally just using 'unsafe' vehicles.

Seems like Mexicans are not punished for taking off the muffler or generally just using 'unsafe' vehicles.

When I visit Juarez, I'm always surprised to see all of the used school buses that are no longer considered road-worthy in America that area used for all kinds of things. Very often they leave the names of the American schools on the side.

This is what the article should have been:

> Maximum length of a truck with a semi-trailer in Europe is 18.75 meters. Some countries have some exceptions, but generally that is the rule. In order to use the maximum of this length for the cargo the tractor unit has to be as short as possible. The best way to achieve that is to mount the cabin over the engine.

That's it. Headline with a question and that one paragraph. This article to me is an example of why articles on the modern web are bad. All the rest is there to keep you on the page longer and get better SEO.

It's not likely that Europe would move to traditional cab trucks if they relaxed the length rules since they still have to deal with the tighter road and parking conditions of European infrastructure

European cabs are traditional.

At least in Europe

Depends on what drives the requirements. The cabin over engine design is probably a bigger PITA to service. If that adds $, people would move away from it.

The other thing to consider is driving distance and how it drives design. I would imagine the count of trucks that need sleeper compartments is much higher in the United States, and adopting a design that keeps parts more consistent for sleeper cabin and non-sleeper models probably has manufacturing benefits.

>The cabin over engine design is probably a bigger PITA to service

not really, the whole cabin lifts up: https://i.imgur.com/pqXW1YH.jpg

Where's the engine? That level of access looks absolutely abysmal and a huge pain for the maintenance technician, compared to this:

https://www.dreamstime.com/brown-big-rig-semi-truck-open-hoo...

Given the regulation prevents this counterfactual from being tested at all, this is really just speculation.

I guess you didn't read the rest. The fact that European drivers also don't care about living quarters was another big reason. Additionally, regardless of whether there's a legal length requirement in the EU I would assume drivers would still choose the cab over engine design due to maneuverability in tight urban settings (also mentioned in the article).

I quite liked the other information provided. You suggesting that an article should contain less information seems quite silly. You know what you could do? Don't read the rest and you won't have an issue....

They could have put the answer to the question in the title at the top and follow with sections on pros / cons, history, etc. But that would lower reader numbers.

Anything about if the difference would remain if the regulation wasn't in place is just speculation. It's like saying, if C wasn't a hard limit for travel speed, would we have space ships that travel faster than light?

Whilst there is some SEO repetition in the article, there's also a lot more information in there than your "summary", including some of the pros and cons of each and actual descriptions of the different designs.

Pros/Cons don't directly answer the question though. That's just pontificating on the subject to add fluff.

Agree. Reading the whole article was painful. Especially the US trucks that reach "137km/h". Clearly a direct conversion from mph, but it doesn't read great.

So why is that rule there? The article describes the cultural and geographic reasons why the eruopean design is feasible and preferred in the EU, but makes less sense in the US.

Let me tell you about how my great grandmother traveled from Germany in the 1930s in a mail carrier to bring this cookie recipe to the new world.

>> Similar requirements in US have been revoked back in 1986 and trucks now can be much longer.

Why did they do that? Ugh. I'd much rather have the shorter and safer trucks around than the current US designs.

>> In Europe Semi-trucks are limited to 90 km/h

55 saves lives.

>> Cities in US have wide streets and interstate highways are very straight and wide.

#notallcities Too bad Boston doesn't have the authority to regulate truck designs allowed in the city. Or maybe they do and just aren't doing it because of the economic impact of requiring transshipping from highway semis to local delivery trucks outside the city. I wish they would anyway.

> 55 saves lives.

No, it doesn't. It was a pointless law that was seldom enforced and blatantly ignored. It really only served as yet another reason for authorities to pull someone over due to profiling. Traffic is much safer if you have everyone traveling at or near the same speed, rather than having a wide differential on the road. It's also why US interstates have minimum speeds. US highways would be safer if the speed limits were set to something that actually makes sense for the road. I gather from your comment you're east coast centric. There are humongous parts of the US after you get west of the Appalachians where 75-85 MPH speed limits are reasonable and would be safe on interstates.

Safety is much more than a catchy slogan.

> seldom enforced

I think that depends on where you lived and drove. In New Jersey it was heavily enforced for a couple of decades.

The US is lagging behind other countries in lowering deaths. https://data.oecd.org/transport/road-accidents.htm

I think you are both right. In Europe 55 (90 km/h) saves lifes, with some exceptions. Highways are rarely wide and straight, and they are packed with traffic. I cannot imagine a truck happily cruising at 120 km/h here.

Also we pay higher gas prices, no way a truck is profitable cruising at 120 km/h.

> 55 saves lives.

Actually that's not true. [1]

  In 1995 the Republican Congress repealed the 55-mile-per-hour federal speed
  limit law. At the time, the highway safety lobby and consumer advocacy
  groups made apocalyptic predictions about 6,400 increased deaths and a million
  additional injuries if posted speed limits were raised. Ralph Nader even said
  that “history will never forgive Congress for this assault on the sanctity of
  human life.”

  But almost all measures of highway safety show improvement, not more deaths
  and injuries since 1995. Despite the fact that 33 states raised their speed
  limits immediately after the repeal of the mandatory federal speed limit,
  the National Highway Traffic Safety Administration reported last October that 
  “the traffic death rate dropped to a record low level in 1997.” Moreover, the
  average fatality rate even fell in the states that raised their speed limits.

  Higher speed limits have not caused one million more auto injuries. In fact,
  in 1997 there were 66,000 fewer road injuries than in 1995, the year before
  the speed limits were raised. The injury rate per 100 million vehicle miles
  traveled fell to its lowest level ever recorded in 1997. If the injury rate
  on the roads had been as high in 1997 as it had been in 1995, approximately
  17,000 more Americans would have been injured on the roads.

[1] https://www.cato.org/policy-analysis/speed-doesnt-kill-repea...

But how much of that is due to safer automobiles?

How has the accident rate been affected?

The effects were measured right before and after the speed limits were change, and cars did not magically get a lot safer at that exact same time. Thus, automobile safety seems to be an irrelevant variable in the quoted study.

If cars, on average, last 20 years, 10% of cars get replaced in two years time. That can be significant.

I also would think cars that get replaced are driven a lot more kilometers per year, so chances are a lot over 10% of all kilometers driven were in newer cars.

⇒ I’m not convinced increasing the speed limit didn’t make roads less safe.

Reading https://www.cato.org/sites/cato.org/files/pubs/pdf/pa346.pdf, fatality rate dropped from about 1.7 to about 1.6. That’s about 6%.

Eyeballing figure 1 in https://www.euro.who.int/__data/assets/pdf_file/0015/43314/E..., I see a drop that could be of similar size in the EU, too.

⇒ I’m not convinced increasing the speed limits made the roads less safe, either.

In general, highways are about the safest roads, anyways, so you probably would have to look at safety only on those roads with higher speeds to be able to answer the question whether safety went up/down/nowhere.

There's a two year difference between measurements, as described in the quoted part of the above comment. Cars didn't change that much in those two years*, nor did everyone go out and buy new cars.

* Airbags were already mandated in the U. S. at that point, and though I oddly can't find a reference, I believe anti-lock brakes were mandatory at that point, too.

Reading through this, it doesn't sound like ABS was required in 2009: https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/....

Another source says it's been required (federally) as of 2013: https://knowhow.napaonline.com/what-does-abs-mean-on-a-car/.

Man, I could have sworn ABS became mandated standard sometime in the 90s. Thanks for going to the trouble to find references.

How many are attributable to widespread airbag installment. Introduced in the 80s, common by the 90s, mandatory by 98.

I searched a little and saw many references to 15,000 reduced deaths in the 20 years from 1980 to 2000 due to air bags.

It's been long known (yet unpopular to report) that speed variance is what is dangerous, not speed.

Basically the difference between the "common sense speed" for a road and the posted speed limit correlates to accident rate.

I skimmed through the analysis.

Figure 1 is pretty funny, given it's x-axis of 1.5 to 1.7 it on first glance seems to show a 50% drop in the deaths per 100M vehicle miles traveled in between 1996 and 1997 (1.7 to 1.6). That is even though they do show the exact numbers (1.69 and 1.64). But let's blame that on the word processors of the time (1999).

The difference in deaths per 100M miles of vehicle travel between 1995 and 1997 of all States that Raised Speed Limits is -5.6%, while it's -6.3% for the states which kept the old one.

They might be safer for someone who sneaks into a blind spot while the truck is stopped, but there's no reason that can't be solved with sensors and cameras. The longer style is probably safer for the driver in any case though.

> Too bad Boston doesn't have the authority

Boston most definitely bans trucks on certain roads. That’s their authority shining through.

Enforcement is practically automatic on Starrow Drive.

https://www.boston.com/news/local-news/2021/08/19/boston-sto...

55 saves lives.

I'm not sure that it it does based on accident statistics, and probably the best thing they could do to increase road safety is to remove the truck speed limit in my state, either let everyone go 70mph or everyone go 60mph, but don't intentionally increase interactions between cars and trucks by giving them different speed limits.

One thing 55mph does do is help with gas mileage. I drive a hybrid and get around 48 mpg at 55mph and 41 mpg at 70mph. This is a relatively aerodynamic sedan, I'd imagine that the difference is even greater for trucks and big SUV's.

As far as big SUVs go, I drive an '04 Ford Expedition (parents gave it to me years ago when they no longer needed the child transporter and it's stupid easy to keep running).

If I drive 55 mph, I get 20 mpg on the highway. If I "drive with the traffic" in CA, I can get as low as 14-15 mpg.

In my limited experience with LA traffic, "drive with the traffic" means stop-and-go traffic :-) In stop-and-go, I usually get around 52 mpg. Which is why I got the hybrid in the first place, to commute in rush hour traffic, but I bought it just before the pandemic and work-from-home, so never really used it to commute.

Oh, stop and go traffic is real, real bad for me (10-12 mpg). I was talking about matching speed with the person in front of you on the highway. That number doesn't necessarily correspond with the speed limit.

I might have gone to a hybrid or an electric car already if it wasn't for the fact that I lived next to my office and walked to work. Then the pandemic happened and I rarely go anywhere :(

Felt real weird having an apartment right next to your office but working from home because it was closed. Ended up just getting rid of it and moving in with my parents because living alone while not being able to see anyone was not doing kind things to my mental state.

The 55 mph speed limit was enacted as a way to improve fuel economy and reduce the reliance on foreign oil in the 70s. It had nothing to do with safety.

NYC bans truck+trailer lengths over 55’ long, which bans all 53’ trailers.

Unfortunately the city doesn’t do a good job enforcing this requirement, so we have a few dozen people die each year due to trucks that don’t fit on the street hitting a pedestrian or bicyclist.

> I'd much rather have the shorter and safer trucks around than the current US designs.

My grandmother's best friend, when I was a child, was killed by a truck running over her while she was in a crosswalk (legally crossing the street). The light turned green while she was in front of the truck and he ran her over. They are so tall and set back so far, many of them can't see a person walking right in front of it.

I sure made folks mad with the "55 saves lives" throwaway line.

I'm hoping the need to extend EV range brings US highway speeds down to something reasonable, but I'm not optimistic.

In the US, there's a trailer length limit and a limit for the entire consist.[1] Those are separate limits, and the difference between the two allows for a rather large tractor. That's something truck drivers lobbied for. If the limit for the entire length is the main constraint, there's economic pressure to have as much trailer length and as little cab space as possible.

[1] https://dot.ca.gov/programs/traffic-operations/legal-truck-a...

It's perhaps notable that Optimus Prime's vehicle mode is traditionally a cab-over tractor, but in the films, he's conventional-cab. I assume that reflects Japanese and American understanding of what lorries look like. I wonder if American kids who had the toys were baffled by his strange appearance.

When Optimus Prime came out 38 years ago, cab over tractor was much more common. BJ and the Bear, a popular (well, as I remember) early 80s TV show, had the protagonist in such a truck: https://www.gobytrucknews.com/b-j-and-the-bear-truck-still-a...

When I worked construction in my early 20s, I frequently had to drive various large trucks. I FUCKING LOVE the "cab over engine" design. The heightened visibility is everything.

My favorite truck was an Isuzu model (don't remember which) that was as elegant as it could possibly be for driving on narrow mountain roads in southern Appalachia (I covered an area surrounding the Smokey Mountains in TN/NC).

Those Isuzu trucks are still being made, and are popular in Australia, South Africa, etc. Hit Google Images with "Isuzu Truck" for examples.

I think the efficiency impact is important over the highway. There’s a pretty big drag difference. Drag being about half of the force needed for the engine to overcome at highways speeds in the US. Especially if you’re already making efforts to reduce rolling resistance, drag can make a significant impact on the range of electric Semis (plus of course the operating costs and time to recharge and cost and lifetime of the battery).

These things are easy to overlook if you’re just using diesel, but they matter a lot for electric. A cab-over semi might have a combined drag coefficient of over 0.7, whereas the Tesla Semi is around 0.35. So the 500 mile range of the Tesla Semi may be just 375 miles if using a conventional European cab-over design. That reduces the life of the battery as well, increases the proportion of the time spent charging, the cost per mile to charge, etc. And it can’t just be compensated with a bigger battery, either, because the vehicle is already near or at the weight limit.

Drag actually matters.

Length restrictions are generally looser in the US, but there's one very notable exception: 53' trailers may pass through NYC to Long Island on a couple of highways, but may not make pickups or deliveries anywhere in NYC https://www.dot.ny.gov/about-nysdot/faq/are-53-foot-long-tra.... 53' trailers are pretty much the standard large trailer in the US. They are recognizable because they have a little "53" written on the side. Don't bother reporting it to the NYPD if you see one though. They pretty much refuse to enforce laws meant to make NYC safer for its non-driving residents.

Lol do you know how unsafe it would be for 'non-driving' residents if trailers can't unload food and necessary items to NYC? Non-driving residents depend on semi as much or more than anyone, since non-drivers rarely have the means to transport heavy loads without driving (some may have a team of pack dogs or horses I suppose).

>They pretty much refuse to enforce laws meant to make NYC [undeliverable by standard trailers]

Good.

Or, you know, they could use shorter trucks. What a concept.

It's nice of you to opine on how traffic enforcement should happen in a place you (clearly) don't live. The NYPD choose not to enforce traffic laws across the board, and it leads to some dire consequences. In any case, whether or not longer trucks would be better for New York, the decision has already been made that they're not allowed. It's not up to the NYPD to second guess the law.

Do you live in the entire city of NYC? Or do you just like opining on what the entire rest of the boroughs should do? How practical do you really think it is for the entire country to make special considerations for some special snowflakes that can't handle the standard trailer everyone else uses? If you don't like the long trailers, you're free to choose to not shop at grocery stores and other places that may be using them. Free market and all, maybe someone can open up a store than only unloads cargo from short trailers, we can experiment on what is more successful.

If the NYPD enforced (were somehow able to) every single law at every moment to everyone, New Yorkers would be crying to go back to discretionary enforcement in no time.

> If you don't like the long trailers, you're free to choose to not shop at grocery stores and other places that may be using them. Free market and all

The free market solution would be that stores that want longer containers can pay for private roads that don't have the length limits, and then we'd see whether the benefit to them is worth the costs that they're imposing on everyone else.

The free market solution would be to privatize the public roads, yes, at which point the owner of the road would realize it would be much more profitable to allow standard trailers through. Non-drivers would finally start paying their share that way too, as the cost is passed on to the consumer -- more on that in a minute.

As it stands now, non-commercial drivers subsidize non-drivers by paying fuel and other taxes that pay for roads. Commercial (semis et al) benefit everyone (especially non-drivers that depend on commercial drivers bringing in goods to them from outside the city), but due to exponential nature of road wear vs vehicle weight, it actually turns out regular non-commercial passenger drivers disproportionately pay for road maintenance. Non-drivers in NYC are taking drivers for a fiscal ride, and all the while at least one of them seems to be begrudging the very semi trailers that keep them alive.

> non-commercial drivers subsidize non-drivers by paying fuel and other taxes that pay for roads.

The costs of roads are far from fully paid out of those taxes though. So non-drivers are also subsidizing commercial drivers extensively in practice.

> Commercial (semis et al) benefit everyone (especially non-drivers that depend on commercial drivers bringing in goods to them from outside the city)

Only to the extent that their shipping is providing value, and it's hard to assess that given the distorting subsidy that they're getting. They might be outcompeting more efficient alternative modes of transport, or they might be making marginal-benefit deliveries that actually aren't worth the road wear and space that they're taking up if those costs were fully accounted for.

> Non-drivers in NYC are taking drivers for a fiscal ride

Nonsense. The land value of roads alone is a huge implicit subsidy to drivers.

As a non-driving resident of a city where the maximum vehicle length is 12m and this is enforced, I assure you that that is not a dangerous restriction.

Worth noting here that the law is ignored by the NYPD in the outer boroughs but it’s actually pretty much impossible to get a 53’ truck onto Manhattan because there are so few ways onto the island, and the only one of the interstates on which 53’ trailers are legal passes through Manhattan.

And yet here’s a fun fact: it’s actually possible to buy food and necessary items in Manhattan. The NYPD ignores the law but the national chain stores that cover the island do not. It’s actually so easy to make deliveries and pickups that those stores are well stocked and serve residential neighborhoods that are literally some of the densest on earth.

Turns out humans have ways of moving stuff around without 53’ trailers.

> residential neighborhoods that are literally some of the densest on earth.

“Some of” is flexible enough to be completely meaningless, but the top, well, many of the densest neighborhoods on earth are anot in North America and have densities in people per square kilometer similar to or greater than NYC’s densest neighborhoods do in people per square mile.

If I thought they were the densest residential neighborhoods on earth I would have said so.

And I'm sure none of those trucks going into Manhattan come from distribution centers in the outer boroughs, which are in turn stocked by standard trailers.

Sure you can get stuff around in things other than 53' trailers, but I think those in Manhattan have decided that's a bad idea when they actually buy stuff trucked into NYC on those trailers.

Look, 53’ trailers illegally entering Manhattan is a problem. I’ll be the first to admit that. But if you think life on Manhattan is only possible because of a huge illegal trucking operation then I don’t know what to tell you.

The US doesn’t have dense cities except NYC, so you may not realise this but rules against big trucks in dense cities are extremely common globally. I get that this offends you aesthetically and you therefore want to think the people of Paris and London and Munich and Hong Kong are miserable and starving because they don’t let trucks in. But that’s not true.

I acknowledge you're right, life is definitely possible without it.

New Yorkers have decided to keep buying stuff brought on these trailers. You probably have too. People voted with their wallet and decided they would buy the goods that came in on the trailer. The reason is because it's just way more practical, and cost efficient, to go along with the standard the rest of the country is using.

Until 1997 Hong Kong was a possession that functioned much like its own country. NYC is simply incomparable to this situation; NYC is less than 5% of the country. I'd also note the tariffs and regulations on goods coming into Hong Kong were way more liberal than NYC before the handoff, so Hong Kong as able to withstand some higher ground transportation cost than NY can withstand at same price.

I'm going to say one more time: there are > 0 illegal 53' trailers in Manhattan, but not by much. It's incredibly hard to get a trailer onto the island. The tunnels aren't tall enough and only 2 of the 21 bridges allow 53' trailers (they are the entrance and exit to https://en.wikipedia.org/wiki/Trans-Manhattan_Expressway) at the far northern end (~170th St). The bridges are all controlled by Port Authority not NYPD. The trucks that end up on lower Manhattan are lost drivers, not making illegal deliveries to Target and Whole Foods. If the NYPD enforced the law _perfectly_ it would not be "unsafe" like you suggest. It would instead make almost no difference to the availability of goods on Manhattan.

I figured you'd focus on HK specifically. I don't agree it's incomparable, but forget I mentioned it. Big trucks are banned from big cities all over the world. The police forces that enforce those bans are not all sat in their cars playing games on their phones like they do in NYC. And yet life goes on.

I was mostly referring to 53' trailers that go into outer boroughs illegally, and then get shipped in by smaller trucks into Manhattan. Manhattan is still benefitting from these illegal trailers even when they don't go into Manhattan. I'd venture a great deal of goods in Manhattan come in this way.

Basically all your examples of cities involve places where the nation's trucking industry expects their major cities and a large portion of the populace (or in HK case, basically the entire territory) to require these shorter trailers. This isn't comparable to the situation in the US, and the result is that for pragmatic reasons NYPD have turned a blind eye to a poorly workable regulation. And it becomes doubly unpragmatic when we already in a situation where trucker drivers are scarce even before having to split their approach in two (travel NYC compliant, or travel rest of nation compliant).

They could be illegally transferring loads to smaller trucks in the expensive outer boroughs, or legally in Westchester and NJ where land is cheaper. It makes no difference to my point, which is:

There are almost no big trailers delivering goods to Manhattan. It works well, just like it works well all over the world. It allows people to move around more quickly and safely. It works well even though Manhattan is ~1% of the US population and doesn't dominate economically to the extent of some world cities. It's certainly not "unsafe" (?!) for the residents of Manhattan (a direct quote). I don't know what "unpragmatic" means when applied to a system that works.

Banning big trucks from places where there isn't room and they get in the way is great. I hope they ban them in more places. I hope they ban anything bigger than a Transit van. I hope they transfer enforcement to a less corrupt, lazy, anti-city/pro-suburb agency than the NYPD. In short: big trucks in cities suck. I'm done.

> It allows people to move around more quickly and safely. It works well even though Manhattan is ~1% of the US population and doesn't dominate economically to the extent of some world cities.

>There are almost no big trailers delivering goods to Manhattan

You keep focusing on Manhattan. We were talking about a regulation applying to NYC as a whole. If no one wants or finds it economical to take these trucks in, then the regulation isn't needed. Therefore you should be fine with deregulating truck length.

>I don't know what "unpragmatic" means when applied to a system that works.

A system that works so well, that people have to work around it, to the complaint of one New Yorker.

>It's certainly not "unsafe" (?!) for the residents of Manhattan (a direct quote).

An intentional misrepresentation, and modification of my quote; but nice that you cowardly run away "I'm done" after quoting me in this manner.

> I hope they ban them in more places. I hope they ban anything bigger than a Transit van.

You hope for a lot of odd things. I could hope you are banned from NYC, but instead of hoping bad things against people I'd rather just allow people to live and come in with the trailers that keep things simple and pragmatic for the trucking industry so truckers don't become an even rarer commodity at the expense of a few unusually fearful minority of New Yorkers.

"You keep focusing on Manhattan."

Because we were talking about what effect a ban on large trailers would have, and that's the only place in the US where there are no large trailers. We could have talked about ~all the capital cities of Europe if you'd preferred. Or the entire island of Britain.

"An intentional misrepresentation, and modification of my quote"

Well, it doesn't get better when I quote the full sentence, but here it is: "Lol do you know how unsafe it would be for 'non-driving' residents if trailers can't unload food and necessary items to NYC?". Large trailers can't unload in Manhattan. 53' trailers can't even be on freeways in much of Europe. It's not unsafe. No one starves.

Well if Manhattan is the only place in US not getting a net benefit from large trailers, you pretty much proved the point of how dumb it would be to enforce a ban on these trailers on the whole of NYC. Manhattan is just one borough of NYC. The regulation is pointless if the truckers already don't go there -- those who go there by accident would have broken the law anyway (didn't mean to go there) and those who are intentionally going somewhere to unload never end up there because by your own statement they can't even unload. Let the trucks go on to the outer boroughs so those in Manhattan can keep benefitting and buying the goods that come off these trailers.

NYPD are apparently acting 100% rationally and sober here by choosing not to enforce this regulation, and you've done nothing but systematically prove that point.

“That is also why Australian highways feature well-known road trains – extremely long distances and straight roads allow semi-trucks to pull up to four trailers.”

Driving around double-trailers in Indiana always made me anxious, so I had to see this unnerving statement in its reality, and I found this article [0] that talks about Australian road trains. Evidently they are used on single lane roads in the Outback, which makes sense. But, I am still wondering, as there must be some warehouse to transition to single-trailer loads or else they wouldn’t be able to safely do last-mile delivery?

[0]: https://www.smart-trucking.com/australian-road-trains/

You just park the truck and disconnect the extra trailers, usually there's a lot on the outskirts of town where the local short-haul trucks will take the trailers to their final destination.

Driving around double-trailers in Indiana always made me anxious

A bunch of American states permit triple trailers. Each individual trailer is a little shorter, but seeing all three going around a corner is a bit unnerving. Especially if they're heavy-load trailers that haul stuff like gravel or ore, because those are much longer to spread the weight out.

Answer to the question in the title, hidden deep inside the article: Length limits.

"Maximum length of a truck with a semi-trailer in Europe is 18.75 meters." so length is at a premium that cannot be outweighed by the other benefits of the "classic" US style design.

Higher speeds and bigger roads are other reasons to have the US truck in the US but not Europe (among many other advantages of the design) but the stated fact that "European style" trucks were much more common in the US when the US still had length limits indicates that the length limit is the deciding factor.

I work for John Christner Trucking. We made it (almost, sorta) to the front page of Hacker News!

Anecdotally from playing Euro Truck Simulator, shorter trucks are also helpful in German zipper merge lanes, which are quite a bit smaller than typical US merge lanes. This article has a pretty good photo.

https://www.ozy.com/the-new-and-the-next/german-roads-are-sm...

Another significant advantage to the conventional design over cabover designs is the heat issue. The heat coming off the engine is significant, and if you can move the cab behind the engine instead of over it, it's much easier to keep the cabin cool in the summer. Large parts of the US have significantly hotter summers than those found in Europe, so this is a big issue for much of the US.

I'd never heard of a "semi-truck". I've always known of them as "artics" - short for articulated.

Source: my childhood best friend's dad was a truck driver (not artic though) and a day out in the lorry was one of the best things to do in the school holidays.

EDIT: I notice the linked article "why are they called semis" actually calls them articulated.

Basically, they're semi trucks because they pull semi trailers... which are trailers with rear axles only

US trucks have a more ornate design, while European ones are blockier

I find this very similar to US vs EU fridges: US ones are metallic, rounded and bulky, European ones are, in new kitchens, integrated behind cabinet doors that look the same as the other cabinets, a more minimalist design.

But then why does software/apps from the US look so minimalist like the European fridges?

Johny Ive did it.

Last point is a big one, geography of roads traveled is vastly different

In general, true.

However, try driving the spectacularly scenic US550 road through the San Juans in southern Colorado, and note the completely regular semi-trucks negotiating this insane mountain road. I am sure this is not the only example.

I find it funny that in US English we've reached a point where the big trucks are called "semi" (as in, "half") and the pick-up trucks, which are the smallest trucks you can make, are simply called "trucks".

> Finally, roads in US and Europe are very different as well. Cities in US have wide streets and interstate highways are very straight and wide. In Europe trucks have to deal with narrow streets, winding country roads and cramped parking spaces.

Most comments in this thread are underestimating this point. I grew up in Italy (where virtually all trucks are cabover), and I now live in Australia (where conventional cabs are common). The road conditions are completely different. Can you imagine a conventional driving through Florence? Obviously it wouldn't be ideal.

There are also lots of European trucks that can't drive everywhere in Florence. There were roads in Borgia, Spain my navigation system sent me down in a rented passenger car where I literally want able to turn because it was too narrow.

Till the regulation is gone, everything else is just speculation about what would happen without it.

Finally! Someone who asked and explored this question!

I had this same question for years :)

Agreed :)

But I'm not quite sure I'm satisfied that this explains why they are so different. It is hard for me to believe that American semi-trucks are more fuel efficient than European ones (fuel is so much more expensive in Europe!), but this article seems to imply that they are.

Cab over is a less aerodynamic shape (it's essentially a box). Conventional designs allow more aero features.

> Conventional designs allow more aero features.

“Conventional” is such a poor label. Convention depends on the context. The conventional form factor here is cab over.

Like when Americans talk about a 'full size' car they mean an over-size one in our perspective.

Conventional in terms of trucks overall, cabover did not come first for trucks, nor is it a conventional design.

It's not uncommon for non-cabover to be referred to as conventional. GP is using the correct terminology.

https://www.innomotivesolutions.com/about/blog/item/cab-over...

https://www.smart-trucking.com/cabovers-make-a-comeback/

https://powertorque.com.au/cabover-vs-conventional-and-euro-...

I am not saying they were wrong, just that the terminology is stupid. Convention has nothing to do with what came first.

I'm saying your reasoning for why it's "stupid" is wrong.

Non OCE is conventional and OCE isn't, plain as that.

Aerodynamics.

Fuel is more expensive, but not more expensive than trimming 8 feet off of the trailer (and reducing hauling capacity).

I don't believe the US trucks have more efficient engines (yet--this is changing due to new EPA standards.) They just haul more, which is a more efficient use of expensive drivers in addition to making the most of the engine's fuel consumption.

I appreciate that explanation, thanks

> They just haul more

Not really, they are just longer. For example the US interstates have a rather strict total weight limit (even by European standards) of 36 tonnes. Where I live, the general legal limit is 76 tonnes, and there are specific (every-day) routes with vehicles weighing over 100 tonnes. Granted, such heavy trucks with special permits are longer than the 18.75 metres mentioned in the article, but even then you wouldn't want to make them any longer by wasting space for an overlong cab.

Weight, the longer wheelbase US trucks haul less total tonnage than the shorter wheelbase EU trucks purely due to regulations? Or are you talking about rare cases that hit the limit? Because I would never have suspected that.

Interesting; thank you. It looks like the federal limit in the US is 40 tons; some states are higher and others are lower. EU appears to mostly limit to 44 tons. Extensive freight rail in the US precludes much of the need for special high-tonnage routes, though you’ll see unusual items transported on trailers with extra axles from time to time.

Aerodynamic efficiency matters much more in North America as average speeds are much higher over much longer distances. Wind resistance increases with the square of speed, so it is entirely possible that American trucks are burning more fuel per mile in spite of being more aerodynamic.

One of my favorite shows as a kid was "B. J. and the Bear" about a trucker and his chimpanzee oddly (now that I think of it) named Bear:

https://duckduckgo.com/?q=bj+mccay+bear&ia=web

Yes, the truck is cab-on-top as well. :-D

Seems like the engine forward design could be made safer with the ubiquitous vehicle cameras of today, but neither the article nor the Volvo video make mention of them.

We have a mix here in Australia, which makes sense I think. I wonder if the long nose form factor gives any benfits for road trains. Long, long distance and big power requirements often on dirt roads. Perhaps you get some stability and comfort benefits. Moreso I think you just don't have to figure out how to stuff all that power in a tight form factor, which is just easier.

>In Europe Semi-trucks are limited to 90 km/h

Wow! That's slower than almost every freeway speed limit in the United States, barring some urban spots.

That's also slower than every freeway speed limit in Europe for cars. Trucks just have a lower speed limit. They are also limited to 80 km/h where cars are limited to 90 km/h.

IIRC trucks also get special speed limits (usually to 80 or 70) on some difficult highway spots, they also often et additional semi-dedicated “slow vehicle” lanes on climbs.

Interesting. I think parts of the US had truck speed limits, but we no longer have them. Same with night-time speed limits.

Trucks (almost all cabover) are limited to 80km/h in Japan, even in highway limited to 120km/h for cars.

I see cabover trucks (or at least trucks with snubby little noses) all the time in the US, in the city. I only occasionally see a traditional tractor trailer anywhere other than major roads and highways, because they're a great big PITA to maneuver. I assume that they have some significant advantages on the freeway, or they wouldn't remain popular for that.

Isn't field of view much better in the European version?

I've only been a passanger in an EU semi and I was itching to drive it, because just how high you were and how much you could see! It reminded me of the Homer's car from the Simpsons - ugly but you can't help but wonder how pleasant it would be to operate.

A few months ago I filmed the long lines of trucks in Georgia (the country) waiting to cross the Russian border. Here's lots of Euro-style trucks if you're interested.

https://www.instagram.com/p/CUIvO1fIfFV/

> This is what conventional cab trucks look like – these are much more common in US, Australia and elsewhere outside Europe.

Where, exactly? Do an image search for "China truck" or "Japan truck", and they're cab-over-engine.

https://www.roadprobrands.com/blog-posts/what-happened-to-ca...

Cab-over designs are used for things like garbage trucks.

When I worked in transportation, people said they faded away because of crash-protection.

My favorite cab-over semi is from the minibike chase scene in Terminator 2

If others are wondering what a road train looks like:

https://en.wikipedia.org/wiki/Road_train

TL;DR overall length restrictions.

The US had cab-overs too back when we had length restrictions but the marginally more expensive operating cost and greatly reduced operator comfort resulted in conventional trucks taking over once those restrictions were lifted. Applications where length matters a lot still use cabovers.

I always wondered this too. Australia seems to have the American style truck too. I find them a bit more fun and less “serious looking” than the European ones.

I think European lorry drivers mostly sleep in the beds above the driving area no? Where do US truck drivers sleep?

I was a little curious if there was a difference in honking power. Now that it became political to honk at the world.

I've always been curious what the live-in cabs are like in those big US rigs. Anyone got a good article?

I don't know a good article, but for some reason I was curious at one point and discovered the marketing pages for various big rigs. Marketing materials presumably showcase more flashy features and higher trim levels.

Also the /r/Truckers/ subreddit has users post their setup sometimes. But usually those are either "look what I was able to cook" or "check out my gaming setup".

https://www.peterbilt.com/trucks/highway/model-579

https://www.volvotrucks.us/trucks/vnl/interior/

https://www.macktrucks.com/trucks/anthem/features/

Where I live, the only requirement in a semi truck is an area to store large volumes of meth.

“I’ve got a semi” means something very different to right-pondians.

why do European trailers have 3 axles instead of 2?

I have wondered the same thing. My guess is that they use three axles with 6 tires, whereas the common North American trailer has two axles with 8 tires. The axles are mounted on a sled so they can be moved forward or backwards depending on the trailer weight to achieve the required weight distribution.

Euro trailers appear to be shorter and probably carry lighter loads, so they need fewer tires and maybe do not need to be adjustable. But not really sure.

> and probably carry lighter loads

The EU standard is 40 tonnes (88000 lbs), usually in 2/3 or 3/2 axle combinations (2/3 usually includes a lifting axle).

Some countries have higher limits e.g. Finland allows up to 76t with special permits

both designs are equally good a blocking road.

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