Our Tesla Model 3 Hasn't Delivered Big Savings in Maintenance Costs | Hacker News Reader

Our Tesla Model 3 Hasn't Delivered Big Savings in Maintenance Costs

caranddriver.com

24 pointsclouddrover53 comments

"..part of the issue is that the Tesla version of these tires start with 1.5 32nds of an inch less tread depth than the off-the-shelf MXM4s. Although it might not sound like much, that's 20 percent less usable tread depth. "

that's a pretty shitty way to cut costs if that's true; they should at least give the 'tesla version' of the tire a new designation -- at least then it wouldn't look like an obvious attempt to hoodwink consumers.

a charitable take would be that they're shaving tires[0] so that their car has better tire performance , and that this process is actually costing Tesla money... but I somehow doubt it -- and if that IS the case the tire should still be re-designated given that a third party is taking it upon themselves to modify the rubber.

[0]: https://www.caranddriver.com/news/a18743693/the-lost-art-of-...

They aren't shaving tires. OEM tires are specifically designed for the vehicle and come direct from factory.

Reduced tread depth is mainly for meeting rolling resistance targets and to increase EPA range.

Source: I am in the automotive industry

They do this for motorcycle tires too. Tires normally made in one factory, tires “stock” made in a different factory like Brazil with much less tread.

That's weird, I'm at 25k miles, my model 3 tires are pretty close to new, and ICE drivers have commented that the tire treads look good.

I'm not a tire expert, but I've heard that there are huge differences in tire longevity, and for people that live near water should be using the higher longevity tires to reduce microplastics.

And if you live in the SF Bay Area, the microplastics in the ocean are mostly tire microplastics, not straws or bags or beads in shower gels.

Regenerative braking saves a lot of brake pad material at the price of increased wear of tires. Additionally, tires are formulated for energy savings at the price of longevity. In other words, it's normal that they wear off fast

How does regenerative braking increase wear on tires? I imagine the forces are the same to the tire.

How does bake Regen wear tires more thab regular braking?

I could see a situation where regenerative braking is generally more "grabby" than traditional braking, and so would result in generally more short stops/more intense pressure on the tires per stop, which over time would lead to increased tire wear

But regenerative braking isn't as hard as normal braking. If you relying on it you will generally have longer braking distances.

> That may be an extreme example, but it proves the point that having a high-voltage charger at home or at your office is critical if you want to reap the potential financial benefits of going electric.

Bullshit. We drove our Model 3 for over a year using L1 charging. My commute was 50 miles roundtrip and we could put 60 miles back on it charging over night. We only ever charged up to 80%.

With random outings and errands we'd be down to around 150-180 miles and would just top it back up over the weekend.

It was less convenient than an L2 charger but plugging your car in every night when you get home really isn't much more hassle than charging your phone.

The model 3 is more efficient too. The model 3 gains about 5 miles per kwh, but the model S only gains 2-3 miles per kwh. You get less in cold weather because a lot of power is diverted to heating the batteries. Even in San Jose, in the winter, charging outside dropped my miles gained to 1 mile per kwh on L1.

Higher amps are also more efficient. I believe the tesla mobile charger on L1 is 70-80% efficient whereas running at 40amps is 80-90% efficient.

The car’s energy meter can’t be trusted. The energy the car sees vs the energy the power company sees is different.

> You get less in cold weather because a lot of power is diverted to heating the batteries. Even in San Jose, in the winter, charging outside dropped my miles gained to 1 mile per kwh on L1.

When a Tesla is cold it will put an upper bound max on the charging rate but that limit is beyond what L1 is capable of, something like 17 amps. The Tesla will also pre-condition the battery for charging if necessary, it does this in hot or cold weather, and until that's complete the car won't be reporting much of a charge on L1 but that pre-conditioning is less than 30 minutes. When you are sitting in the vehicle, it will use power from the charger rather than the battery and, with climate control, on L1 charging will report a 0-1 mile per hour charge rate.

There are numerous videos on Youtube refuting the claim that you can't charge on L1 simply by plugging the car in and walking away for several hours to demonstrate that the car charges decently on 120v in cold temperatures (-28F).

Hmm, should changing the windshield and sunroof due to damage count as “maintenance costs”?

I think it’s useful to know that the cost of a new windshield looks 4-5x what it would be on a toyota corolla, but I think calling these high “repair costs” would be more accurate

The article does say that those costs aren't included in the maintenance total.

But considering that they replaced the entire windshield (and sunroof glass) for what they describe as a stone chip, I'm inclined to believe they may have been overpaying or overdoing maintenance anyways. AAA suggests the price to repair a windshield chip would be around $100, and that replacement isn't necessary if it's smaller than a quarter.

That's exactly what the article does. They don't include the windshield replacement cost under maintenance, they tally it under "repair & damages"

> Hmm, should changing the windshield and sunroof due to damage count as “maintenance costs”?

I am OK with the classification used in the article. A head-on collision would certainly be repair, not maintenance. But chipping a windshield or roof is IMHO maintenance, because it is expected to happen with a certain frequency and you can't really avoid it.

Odd, then why does insurance pay for it in many places? As if it was an accident. In CA and VA and probably many other states, $0 deductible.

In GA you have to pay the deductible unless you opt for additional glass coverage.

So in GA, it's still considered an accident, not a routine* wear situation.

Edit: spelling

Yup, it's accidental.

Breaking your windshield is an accident, according to your insurance.

Did I miss how they are calculating "fuel" costs? Seems like on of the big differentiators would be that cost.

If it really is 29 kWh per 100 miles[1], and the median energy rate is $0.1042/kWh [2], that is slightly more than $3/100 miles in "fuel" cost. Versus 4 gallons of gas (median fuel mileage of 24 mpg[3]) being $3/gal [4] so an equivalent cost of about $12. How do they account for the $9/100 miles saving? (they said they drove 3500 miles in a month which would be a savings in gas expense of $315 / month or am I missing something here?

[1] https://en.wikipedia.org/wiki/Tesla_Model_3#Specifications

[2] https://www.energybot.com/electricity-rates-by-state.html

[3] https://www.bts.gov/content/average-fuel-efficiency-us-light...

[4]https://gasprices.aaa.com/

One thing that is often overlooked is the vampire drain on EVs. In my experience, Tesla’s can use anywhere from 1-3 kwH every 24 hours sitting idle. The loss is due to keeping monitoring and connectivity on. It’s not an exact science, but if you let your car sit for days then you can expect to have less range than when you left it.

Yes, they’ve made improvements (there were claims of 10+ miles of range lost per night on Model S). There is a deep sleep that seems to kick in after awhile. You can turn off mobile connectivity to help save watts.

Overtime, these little losses add up. It’s not something the car tracks, either. In fact, Tesla’s odometer omits the vampire drain and only shows you energy used while driving. You need a separate energy meter on the charging outlet, or a smarter charger that measures all power being used.

I've noticed my Model 3 loses several miles a day. On the other hand my Leaf can sit for a week or more and show no loss.

a car burning 100w sitting there idle (2.4kWh/day) is ridiculous. I hope this isn't right.

I’ll also add that some people ignore this (or are obvious to this) because the car has 300+ miles of range. What’s a few miles lost the next morning? /s no big deal.

I’m a big tesla fan. But, sometimes the math doesn’t work. Especially if you aren’t driving it everyday.

Search Tesla vampire drain, it’s a thing.

The calculation is muddied even more because the tesla odometer doesn’t monitor two important things: vampire drain, and charging inefficiencies. The odometer only tracks power while your butt is in the seat (so if you park the car and use the ac, it will track that). This makes long term cost tracking hard: you can only depend on the miles driven metric from the car. You’ll need a separate meter to track total energy used to account for inefficiencies (power lost to heat and conversion) and vampire drain.

The car shows kWH used since last charge, and it almost never matched what my smart meter measures if the car has sat for days.

I can definitly be more if you let your Tesla out in the sun. The Tesla will protect it battery by cooling them appropriately. So active monitoring + cooling, 2.4 kWh/day is appropriate.

1-3kwH every 24 hours would be between 41 or 51 watts per hour, correct?

Maintenance costs never include fuel.

Okay, that's fair. So "nearly equivalent maintenance costs but a whole lot cheaper on fuel" would seem to be a less click baity headline. (I know, I'm asking for a lot)

The current title is not clickbait. The promise of lower maintenance costs has been front and centre in most EV marketing. If it turns out to be untrue and someone points it out, I would consider it a PSA not a clickbait.

One part struck out to me:

$100 for tire rotation?

I used official Tesla service. They came to me and only charged $25 to rotate them.

Oddly enough I mentioned checking the brakes. And they told me they were fine, nothing needed. This was at the 15k mark.

I had my 2 year scheduled maintenance done last Nov and it included a tire rotation all for $97.50.

* That's the only maintenance cost I have incurred so far since I purchased the car in 2018. Tires are fine even after driving from GA to CA.

The early versions of the Model X were trash too. Tesla has some serious quality control problems.

But the market doesn't really care apparently. They are now the largest car company in the world by market cap ... while making one twentieth the number of cars that Toyota does ... at vastly poorer quality.

It's as if your assumption that Tesla QC hasn't changed is wrong.

> But the market doesn't really care apparently.

Shorter term the market is frequently irrational and inefficient, highly susceptible to wild swings in investor emotion and speculation (see: meme stocks, aka high-flying pump & dump stocks, which existed 30-40 years ago too). You get rich in the market by taking advantage of how predictable and unchanging human behavior is. The market is made up of emotional humans, most of which struggle to be rational about very simple investment decisions. They frequently panic sell and panic buy. They fear standing alone above all else, so they sell when everybody else sells, and they chase-buy when everybody else is chasing (FOMO prompts remarkably foolish behavior when it comes to investing and speculating). Even the supposed pros on Wall Street are overwhelmingly mediocre when it comes to making rational investment decisions, and very prone to chasing fads (and getting buried by them), which is why their track records are so often subpar. They're consensus machines terrified of their own shadows (nobody ever got fired for buying IBM, same mental concept but applied to portfolio management), so they inevitably consensus slink down below the S&P500 average.

There isn't a single prominent US stock of the past ~50 years that has floated perpetually at an extreme valuation without delivering the goods. Often hitting expectations just gets you years of compression regardless, after having pulled results forward from so far into the future (Microsoft more than tripled in size and the stock went sideways for 15 years; compression). Tesla has to continue to deliver, or else. Short-term people lose sight of this fact of market history, that no stock actually escapes reality. They get caught up in thinking whatever the context is today that it'll continue to be the context. That was true in the speculations of the 1970s, 1980s, 1990s, 2000s, 2010s, and it's just as true today. Short-term often feels longer than it really is. A few years is short-term, not long-term.

Name any of the prominent hyper valuation tech stocks from the 1990s or 2000s that didn't either deliver on the growth promise (AMZN, GOOGL, NFLX, etc), implode (long list of dotcoms as one group example, or eg solar stocks from the commodity bubble of 2006-2008), or compress/stagnate sideways for many years (MSFT, INTC, CSCO, ORCL, etc). No stock escapes reality, they all ultimately have to deliver or else. Tesla won't be different.

Tesla is floating on immense expectations that they'll eventually become larger than companies like Toyota. And they're also floating on their significant growth in recent years (that's obviously the fuel for investors that keeps them believing the longer term story). Either they continue to deliver on growth expectations, or the consequences to the stock are obvious - the market cares very much about whether they continue to deliver.

I’ve never heard of annual brake lubrication in areas that use road salt. Seems excessive to me. I’ll wait until they start screeching and do it then maybe.

Modern calipers have slide pins that they move on (so that you only need pistons on one side). These can freeze up, and your brake pads won't wear evenly. By the time it starts screeching, the friction material is gone, the steel backing plate is rubbing, and you're replacing the rotor too. (I actually fixed this exact problem on a Ford truck the other day)

I have found that most auto shops always replaces the rotors. Not quite sure why. Maybe new rotors are just thinner so they can't be resurfaced? Or maybe it's just to save time. Or maybe since break pads can last a really long time it's just makes sense to always do both.

New rotors are cheaper than using a break lathe.

(There's a lot of Brake Lathes for sale on CL.)

Are you aware that most EV drivers rarely use the brakes? At 50k miles, mine look new.

Even if you rarely use the brakes, seems to me like a good idea to keep them functional. And based on my experience working on old, worn out shit, the less something is used, the more likely it is to get corroded or gunked up and not work.

I'm not sure who was advocating non-functional brakes? I looked around the conversation and didn't see anyone with that opinion. I mean, maybe you think yuppie_scum thinks that, but in my case, I know my brakes look like new because they were inspected.

On a Tesla the pins the calipers ride on can seize due to corrosion from road salt used in some places during the winter. It's recommended maintenance to inspect and lube them. I've only driven in the southern US so it's not been an issue for me and my brakes were fine when inspected last fall.

My Nissan Leaf's brake rotors rust up and I have to do a few hard brakes every month or so to clean them up.

Aren't Tesla's brakes supposed to last a really long time because of regenerative braking anyway?

That's actually why they need the lubrication. They are in use a lot less and so can seize up.

If you drive in Hold mode, you rarely need to use the brake pedal. https://www.tesla.com/support/videos/stopping-mode

The brakes latch in Hold mode so while you aren't using the brakes, the car is using them.

That being said, they don't engage until the vehicle has come to a complete stop so there's probably little if any wear incurred.

Thanks for the clarification, edited my comment to indicate "brake pedal" :)

How did Tesla hasn't catch on to drum brakes?

Check out how much flak VW is getting for using drum brakes in the rear of some EVs.

I thought they’ve got praise? They aren’t the only ones who got em either.

Reply on news.ycombinator.com