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When I was seventeen my dad said I could have the old family station wagon to drive if I would replace the water pump on it. He got me a water pump from a junk yard and the appropriate Chiltons manual for a 1973 Chevy Impala and it took me about four days (real mechanic time would probably be 4 hours) and then my dad sold me the car for $1.

Some things about it stand out in memory. Engines were so big and un-compacted back then it was relatively easy to fit your hands and tools where ever they needed to go and pieces of the engine basically looked like what you’d expect them to be.

The other thing I found out later was that my father was desperate to sell me the car, because it allowed him to get me off his insurance. I was a 17 year old boy, with one fender bender already under my belt and my parents had just bought a new Mercedes sedan. For insurance purposes, as a licensed driver living with them, without my own car the insurance company considered me a driver of the new car and the insurance was outrageous. After my dad sold me the car, I was off their main policy and on a separate one. Very tricky dad.

Something that is extremely anecdotal experience for me, especially given I have never owned a car, is that things like "check your oil" are weirdly a feature mainly of american media. To the extent that its sort of led me to believe its something that isn't really necessary, like taking vitamins when your doctor hasn't told you you have a deficiency. I'm only really realising this assumption of mine now, so is this even remotely true?

I don't think ive ever heard about people talking about changing their oil here in europe in actual day-to-day life, but I have heard much more about antifreeze or windscreen wiper fluid or even water/coolant.

I looked up the oil change schedule for my car once. Same car and specs available in both the US and the UK (minor compliance issues like colour of indicators beside.) In the UK the manufacturer recommends changing every 20,000 miles or two years, in the US every 5,000 miles or six months. Same car!

I have never changed my oil in my car, despite having it over a year, and won't look to do it for another year yet. I think that would give most Americans a heart attack.

They've got an entire industry over there changing oil 4x more frequently than actually required.

Absolutely bizarre.

I presume that the UK schedule specifies synthetic oil, that does let the oil last a little bit longer. But not that massive difference.

One of the reasons people give for buying German luxury cars is because they only need the oil changed once a year vs the 3-4x a year for American or Japanese or Volkswagen cars.

> One of the reasons people give for buying German luxury cars is because they only need the oil changed once a year vs the 3-4x a year for American or Japanese or Volkswagen cars.

No clue about American & Japanese cars, but for VW (and Opel) it's definitely just once per year (in Switzerland).

> need the oil changed once a year vs the 3-4x a year for American or Japanese or Volkswagen cars

We bought a VW Polo, kept it for ten years, then changed it for a VW Sharan, and recently added a VW Up. Total miles driven must be around 200k.

Based on a sekrit strategy - called reading then following the service manual - can confirm that (at least our) Volkswagens do not need their oil changing "3-4x a year"!

Are you in North America? The OP said that North America and Europe had very different oil change schedules. I haven't owned a Volkswagen for 30 years, so I guess it isn't surprising if it has changed.

Nope, American/Canadian manuals for VW cars tend to specify 16000 km or 10000 miles. I have experience with mk4 and mk5 VWs (diesel and gas) and they all had similar or the same oil change interval.

https://www.volkswagen.co.uk/en/owners-and-drivers/servicing...

(assuming you're not doing significantly more than 10,000 miles per year) "For the first three years of ownership, your car will require an annual service inspection and oil service."

This seems to be the recommendation for US/Canada too...

This isn't true. The VW service manuals for at least the last 15 years have had a 10k mile service interval for changing the oil and not 3-4X a year.

The plan I had with my VAG garage was a service once every 2 years. No need to change the oil more often than that unless I were to do a lot of miles.

I have a Japanese car (Mitsubishi), made in Japan and imported to Poland, sold with a manual in Polish. The manual says to change oil every year or 20kkm, whichever comes first.

And if it was sold in North America it would say something very different in the manual.

An oil change is cheap. It’s also far better to preventatively change the oil, that way the engine is running with optimum lubrication most of the time. If you wait to change the oil when it’s black sludge, it’s likely damage will slowly build up from allowing the engine to run with poor oil.

So why don’t the manufacturer recommend it? Especially since it’s comprehensively warrantied for seven years so entirely their problem?

Either 5 is justified by engineering or 20 is? One of them must be some kind of misrepresentation?

Maybe the oil sold in Europe is more uniformly higher grade?

If I go to the local auto parts store here, I can spend ~$1.00/qt for oil or more than $10.00/qt for oil. Guess which oil most people will buy?

Also I don't really have any confidence that the dealers are using factory specified oil. I think they probably use the cheapest bulk oil they can buy. That's why I change my own oil, that way I know what is in the engine.

A counterpoint to this is that my car is manufactured in a single plant in Europe. It ships with engine oil in it (because it's driven on and off the transport ship). So I presume one sold in the UK and the US have the same oil in, yet Land Rover will tell you to change that exact same oil in the exact same engine after 20k miles in the UK and 5k miles in the US.

There’s a weird subset of Americans who are very “passionate” about motor oil. They argue about oil filters and formulations… almost audiophile like.

My guess is the guidance is to avoid some PR nightmare.

Fuel and oil quality is a lot more variable in the US, so are the environmental conditions, so you have to set the guidelines according to the minimum likely to be encountered.

Amazing. Not only do the dealers I've used not use bulk oil (unlike most 3rd party shops) but I get the leftover (new) oil in the original metal can they used. It is definitely the factory specified oil. The specific car is part of the paint scheme directly on the can.

Seems to me reading the thread that the difference is because US dealers use crappy oil so they specify more oil changes? Or maybe it's just greed.

Its hard to give a good recommendation as oil degrades at different rates depending on use age and weather. Lots of short and aggressive trips in the city will wear it out differently to some smooth motorway driving, mileage being equal.

Is it really a 4x difference? And don’t British people drive more shorter trips than the US so even if that’s the case it’s also the wrong way around?

Fuel and oil quality is a lot more variable in the US as it’s set at the state level, plus it’s just generally worse, so are the environmental conditions, so you have to set the guidelines according to the minimum / worst case likely to be encountered.

I used to help develop Diesel Engines before I moved into Software Engineering.

If they followed anything like what we did, they would just run load cycles on the engine in a test cell to simulate approximately however many miles of ‘normal’ use they want to validate the engine up to. During the testing the engine would be maintained, fueled, and oiled according to the maintenance schedule and customer guidelines the engine will be sold with.

After the testing, the engine would be completely broken down and analyzed. If there weren’t any signs of abnormal wear then the engine would be considered validated __under those conditions__.

The problem is when real-world use deviates from the testing conditions. Which is pretty much always. Then the manufacturer guidelines no longer apply.

If you run your engine harder than the test cycle load factor, you will need to replace the engine oil more regularly. If your fuel quality is crap, i.e. has any ethanol in it, you will need to replace your oil more regularly as fuel eventually gets into the oil, and ethanol results in high water content in fuels, and hence oil, which will break down seals as well as reduce overall lubrication.

If your engine breaks down due to poor oil quality from lack of regular inspection and replacement, then as a manufacturer I’d be very resistant to paying out on any warranty claim. Even if you followed the “guidelines” for oil changes, you still have a duty to inspect the oil regularly, both as a responsible driver and under the car manual guidelines. Using bad oil and / or fuel is very easy to test for.

Long story short, the oil change intervals guidelines are just that, guidelines, and real-world use dictates the maintenance schedule. Frequent oil changes, before the oil breaks down / becomes crap, is just a quick, cheap way to prolong the life of your engine or any mechanical device with bearings or sliding surfaces for that matter.

> Even if you followed the “guidelines” for oil changes, you still have a duty to inspect the oil regularly, both as a responsible driver and under the car manual guidelines.

No this isn’t true. I check my oil as regularly as the manual tells me to, which is every two years. That’s literally the published inspection schedule in the UK for this car. If that isn’t regular enough and the engine wears that’s a warranty issue covered by the manufacturer.

Most manuals tell you to inspect the oil monthly or before a long car journey.

Waiting two years before realizing your engine is drinking oil is probably reckless which wouldn’t be covered under any warranty.

You mean literally checking the dip-stick? Yes they do recommend to do that more regularly, but if you mean dumping the oil out, they don't.

No consumer law would uphold that. Your 80 year old granny have to be able to see something is wrong with the oil by looking at the dip. Demanding anything else is requiring someone educated look at it which won't hold in any court in the EU.

>If your fuel quality is crap, i.e. has any ethanol in it, you will need to replace your oil more regularly

That is real-world use in most of Europe and is included in the higher mileage between oil changes compared to the US discussed here. I don't even think most Europeans inside the EU have access to ethanol free petrol? At least around here (Denmark) it would be illegal. If a car breaks down because of ethanol in the petrol it is of course covered by the manufacturer. Otherwise they might as well state "warranty 5 years but not if petrol has been added at any point".

The manufacturer specified intervals are just fine and you'd need to be an extreme outlier to have any problems with your oil following them. Maybe if you have a caravan attached at all times or drive off-road or racing or all of the above at the same time. Otherwise consumer law would mandate the manufacturer pay for any damages caused, as it damn well should. It is also the manufacturer that would have to prove the fault is yours. Not possible if the car have been serviced even if done by a third-party shop. The oil would have to be visible damaged even if looked at by a granny (they cannot demand you understand oil better than "it looks like oil and is inside the specified mileage").

Newer cars will usually tell you. Iirc, it averages around 8-11k miles or 4-5 months for my Honda.

It’s a weird topic that people get religious about. I will say that in the 90s when I changed it myself, the viscosity of the oil was very different if you went longer between changes.

Is this possibly related to E10? E10 is the norm in the US but, as I understand it, E5 is more common in Europe. I don't know the chemistry but I do know that there are concerns about ethanol adversely affecting the life of engine seals, moreso in older vehicles not designed for it, but there's at least a fringe of people who insist it's an issue for modern engines as well.

I also know that there are some appreciable differences between EU and US standards for diesel (higher cetane number in Europe) which adversely impacts the performance of small diesel engines in the US, but I don't know if there are any similar issues with gasoline.

I'd also be curious about the manufacturer's specified oil. It is surprisingly common for new vehicles in the US to still specify conventional or blended oil, where 5k miles is a more common change interval. I've seen as high as 15k mile change interval specified in the manual for a US vehicle but the manual also specified full synthetic only (this was a turbocharged engine which tends to adversely impact life, I wonder if a similar naturally aspirated may have listed 20k).

In any case the "change oil every 3k miles" guideline is long gone in the US, with 5k-14k being more common, but nonetheless 3k was common for long enough that it seems to be thoroughly instilled into the minds of many members of the baby boomer generation. I think this has given a certain license to the chain lube shops, long a source of suspect business practices, to continue to use 3k miles for their window stickers. That said I've seen even Jiffy Lube put in a window sticker for 7k miles, for a blended oil. There's a story (I don't know if it's true) that the 3k mile recommendation stuck around for so long only because the domestic automakers were uninterested in going to the expense of longer testing, and that situation changed due to both media involvement (Consumer Reports for example took this on as a big issue in the '90s) and competition from the Japanese automakers that had invested more money into research.

5k actually seems unusually low for a new production vehicle and I would tend to think that must have been specified for conventional or at least blended. Outside of some older engines with detergent-related concerns pretty much the only thing keeping conventional oil on the market is price and more and more vehicles are specifying synthetic only.

Finally, temperatures across the UK are much more moderate than across the US. While synthetic oils have less issues this way, oil behavior in terms of actual viscosity and lubricity tends to vary appreciably by temperature, and worst of all mostly when it matters most right after startup. This has an adverse impact on both oil and engine life. It's become less common for US vehicles to specify different oil grades for different seasons/temperature ranges (although some still do), but US maintenance guidelines are still going to be developed for a pretty wide temperature range that notably includes ambient temperatures in the 80-100F/26-37C range that significantly thin oil and are uncommon in the UK. A similar problem exists at the low end, in parts of the US cold start temperatures of 20F/-7C are routine and most vehicle manuals no longer call for block heat until you get down to nearly 0F. Oil can take a long time to "limber" starting from these low temperatures and that's hard on engine life and puts a lot of metal shavings in the oil. Manufacturers kind of have to set their maintenance recommendations at "lowest common denominator" since practical experience with seasonal/climate-based oil recommendations have shown that vehicle owners and maintenance shops are both extremely bad at following them.

I would expect the schedule for the first $X months/$Y km to differ from subsequent periods. Manufacturing tolerances are incredible these days but there is still going to be a period of high wear leading to less and less new particulate in the fluids. At some early point, months if not weeks or days after the mechanical bits all have experienced a range of conditions, a fluids change would be beneficial. Most of the wear having taken place, it will take much more time to reach the same level of contamination after the first fluids change.

Does your owner’s manual recommend abiding by certain speed/rpm limits during a break-in period? I’m pretty sure my (Canadian) old car/old truck do.

If your car is newish (under 8 years and under 100K miles), you can pretty safely ignore any routine oil checking and just change it every year or ~12K miles. At some oil change, the mechanic will tell you [or you will see] that you have an oil leak or consumption issue and should then start checking it more often. A newer car will use way under a half-quart of oil in 10K miles, which can be ignored entirely.

I change the oil on our CR-V every year (about 5-6K miles) and because it’s 17 years and 225K miles old it uses some oil, which I top up twice between annual changes.

The amount of oil changing done in the US is indeed excessive and driven by promoting the practice to consumers who, in general, couldn’t find their oil filter nor explain the function of oil and oil filtration, and can only judge based on what everyone is doing and whether they can afford it. The little reminder stickers to bring your car back in 3K (yes!) miles are a critical business supply for an oil change franchise.

In the 1980s, with conventional motor oil, 3k mile changes made sense. It was cheap insurance. With engines made today and synthetic oil, 10k mile intervals are not unusual. The quick-lube places will still put 3k miles on their reminder sticker, because it's more business for them.

Also be sure they are actually using the correct synthetic oil for your car, and not conventional 10w40 that would be appropriate for a 1978 Chevy.

The advent of closed-loop fuel control has helped oil service life as well, but I think the “it’s cheap insurance” psychology is a message that makes sense to primitive human brains well beyond the underlying engineering data, leading us to over-service expensive things.

> ... you can pretty safely ignore any routine oil checking and just change it every year...

No, no, no, no, no.

Stretch the oil change intervals a little if you have to, but you need to check the oil on a regular basis.

The oil level and quality are critical to the life of the engine. By the time the oil pressure warning light comes on, you may already have irreparable damage to the main bearings.

In the 1970s and before getting 100,000 miles on a car was a big deal, you would call all your friends for that, put oil in the engine, drive off in a cloud of blue smoke and 10 minutes latter having crossed that mark return and put more oil in. In the 1980s cars got a lot more reliable and so most don't remember how bad they used to be. Few cars, even old worn out beaters need their oil checked between changes, but it used to be a big deal and not doing it's would destroy your engine fast since it would run out.

So mostly it is pandering to old people, but it is still an expression

My car has 160k km since 2005. The problems are everywhere else except the engine

First - it is rusting a lot. Then the car door doesn't close properly when it is colder than -15 or -20. Then the car has decided that the esp is faulty 2 times on longer rides in cold weather and that the max speed should be 20kmh (luckily a restart of the car fixed that)

This is it - a car's structure just rots away at a certain point if it's being used. It's not a mechanical thing you can refurbish or replace - the car as a whole just starts breaking apart.

With the exception of a crappy Dodge which lost a timing chain which took out a bunch of the powertrain (under warranty--but it was never the same again), it's mostly fair to say that every car I've owned was retired due to rust.

  > Some engines can have the head gasket start to leak

It's OK, I drive a Subaru too.

I don't drive a Subaru, but it can be a problem on other makes as well.