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Comment by jdietrich | Hacker News Reader

Most internal combustion engines are only good for ~200,000 miles, even with excellent maintenance. A worn-out engine is good only for scrap, but an EV battery pack with 50% capacity is still very useful as a solar storage battery.

Most of the 2011 Nissan Leafs are still going strong with ~80% capacity. Their outright failure rate is less than 0.02%. Cell and battery pack technology has improved dramatically since then, so I'd be very optimistic about the useful lifespan of a brand new Model S or Chevy Bolt.

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Well crap. Both of my cars have well north of 200,000 on them. I was really hoping to keep driving them for a long time to come.

I had 250k on an +20 year old Toyota pickup, though things slowly start to crap. Leaky carb diaphragms due to ethanol, harmonic balancer wearing out, corroded brakes lines, bad clutch cylinder, dead ignition module. Donated that after buying a new Toyota pickup. Had that for 12 years now with zero problems.

Purchased a used 2015 Nissan Leaf recently and very happy with that. We'll see how the battery holds up.

I think many will ditch their cars not due to engine wear, but for stupid reasons like their smartphone not linking to the stereo.

I think a much better reason that people ditch their cars is the increased safety in the newer models. Very few cars had side air bags and a decent amount didn't have ABS 15 years ago. There are a lot of other improvements surely made that I don't know about.

In Japan everyone junks their cars in 10 years because of the mandatory car check-ups (we pay $400-$2000 every 2 years for the check-up then have to pay every year once the car hits 10 years old). There are some exceptions and I don't know all the rules as I just own one car.

> for stupid reasons like their smartphone not linking to the stereo.

I'm hoping to install an after-market (Pioneer) wireless CarPlay stereo in our 2009 Mazda, assuming it can wire in to the existing reversing camera. The car's just fine, but it's stupid having this double-DIN stereo with a screen that's always turned off because it's useless.

Depends on the kind of car you get, but certain cars regularly get to twice that with proper maintenance. Of course, the interior and exterior start falling to bits around the drivetrain anyway.

In large swaths of the United States (and, presumably, most of Canada) road salt will destroy most cars long before the drivetrains are worn out. Collisions also destroy a significant number (in some cases partially destroying the drivetrain too, but not always). In both cases the drivetrain almost always gets disassembled for parts unless there's something really unimpressive about it. Pretty rare to see a car body go into the crusher with the engine still in it unless it was a bad frontend wreck, at least in my experience.

Electric vehicles will be subject to the same body rust and general degradation issues as combustion cars, and it's not obvious that the residual value of a battery pack is going to be that much higher than the residual parts value of an engine in a rusted-out but otherwise operable gas car.

We'll see, I guess, but it doesn't seem on the surface like the economics are likely to be all that much different on the scrap / recovery side of the equation. I suspect that supply chain and labor costs will dominate the price of used batteries rather than the lithium metal itself.

The barlytery will certainly hold its value quite well, for stationary storage if nothing else.

Also electric cars will have flatter and thicker bottom plates which will rust less. Not to mention that many are aluminum frame.

IMHO in that age range, "proper maintenance" means that you'll replace most of the key parts over the next years.

The difference between maintaining and buying new is thus whether you buy the new parts all at once, or replace them one-by-one as you go..

I replaced the engine and transmission in my vehicle at around 220k. I intend to get another 300k out of it, hopefully long enough for the first wave of cars to be remote controlled into the nearest lake and legislation to be passed requiring some security rating that does not yet exist.

I think you may have to do a Dukes of Hazard with them.

In recent years there's been a shift toward smaller engines with turbochargers. I have heard folks with luxury sports cars (Audis, mostly) complain about the cost of a busted turbo, and I've wondered whether people who bought an ordinary-seeming car with a turbocharged 4-cylinder are going to be in for a nasty surprise at 50k or 100k miles.

But I don't know what the life of turbos is, or if the cost of an Audi turbo replacement is partly/largely because it's an expensive car to begin with. Will Toyotas and Chevys be cheaper?

That rings true - I had a VW, so probably the same engine as in an Audi. I had to replace the turbo at about 100k miles. It cost me £700.

Glad to hear it's not more than that. I feared that this would be big profit driver for dealers doing repairs — and something that most consumers wouldn't consider when estimating the total cost of ownership of a $20-30k vehicle.

Turbos are fairly accessible, and so it isn't a lot of labor to replace (a few hours), and the turbo itself is only a few hundred.

The real worry about turbos is the common failure mode is it starts putting engine oil into the intake. In a gas engine that probably doesn't mean anything, but in a diesel engine that results in a run away engine: max throttle, higher RPMs than the engine is designed for - all while they engine is burning away its own oil that might protect things until the engine explodes. (In modern engines they put throttle valves specifically to shut off air if this happens, but old timers in industry can tell you stories)

Turbos have one moving part which runs (typically) on an oil bearing. They are basically immortal IF run at spec pressure and if not subjected to oil starvation. When you see busted turbos, it generally means it's been run at higher-than-spec boost.

I have a pair of Peugeot Partners(small mini-van cars) from 2001 - they both have turbo charged diesels. When they first came out people were saying that because of the turbo the engine will die quickly. The cars are both 16 years old, and have 250 thousand miles.......each. They are giving away to rust slowly, but the engines run absolutely fine.

I personally drive a 381bhp 2.0 petrol with the largest turbo installed in a production car ever(GLA 45 AMG) and I know a few people who have done over 100k miles in those cars - no problems with the engine.

I'm absolutely not worried about the turbos.

> ...largest turbo installed in a production car ever

Bigger than a Veyron?!

Veyron has multiple turbos, I don't think any one of them is "bigger" than the single turbo used in the 45 line of AMG cars. Well, they might be physically bigger(I don't know), but what I mean is that it provides the highest pressure(28psi) of any turbo used in a production car.

For comparison, Veyron has 4 turbos but they achieve "only" 18psi of boost( http://media.caranddriver.com/files/bugatti-veyron-164bugatt... )

Interesting, thanks!

>"Most internal combustion engines are only good for ~200,000 miles"

Interesting and I think that figure is is generally accepted and I believe this is due to shear stress on the engine block no?

I know older cars that came out of Detroit when engine block were cast iron could get up to ~300k miles(the slant 6 comes to mind) but I believe nearly all engine blocks in recent makes are aluminum now.[1] The referenced article says there's parity between now between the two but that doesn't correlate with my own admittedly limited and anecdotal observations.

[1]http://articles.latimes.com/2000/oct/18/news/hw-37969

It is generally accepted, but I'm not convinced that it is true. I suspect that most cars get replaced well before the engine's ultimate fairly.

In my own (anecdotal) experience, they burn a little oil at 200k, but have plenty of life left in them.

In the days of the Slant-6, cars never got to 300k miles unless they had ridiculously meticulous maintenance. Detroit cars were lucky to get to 100k without falling apart. These days, cars are barely broken-in at that age, and 200k is nothing remarkable. If you're not getting that kind of lifetime, then you need to stop buying a crappy brand.

>"In the days of the Slant-6, cars never got to 300k miles unless they had ridiculously meticulous maintenance"

As the former owner of mid 1960s Slant 6 purchased with ~ 220K miles on it that I personally put another 120K before the block cracked I am telling you that you claim of "never" is just plain wrong.

Aside from periodic oil changes I wouldn't describe my maintenance regime as ridiculously meticulous at all.

There are many vintage Duster/Dart/Valiant owners with cars that have 200K and greater miles on them. Here are some links with attestations that corroborate this fact:

http://www.forabodiesonly.com/mopar/threads/who-has-the-high...

http://www.onallcylinders.com/2014/01/20/top-10-engines-time...

http://www.nytimes.com/2003/12/15/automobiles/autos-monday-c...

http://www.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=ttal...

How ironic that you put it that way, considering that I've known slant 6s with 300K on them. I don't know if they all did that, as I've never known a slant 6 to die, so I'm not knowledgeable of their average life. And every small block Chevy (of that era or a little later) I've owned or knew the owner could easily top 100K. The later American compact four cylinders, OTOH...

Indeed. Both he Chevy small block 350 and Dodge Slant 6 are both considered legendary designs.

> due to shear stress on the engine block no?

What kills piston engines is sliding friction.

Unavoidable sliding friction on pistons, valves, and camshafts results in wear. The crankshaft journal bearings are partially lubricated and wear out. Because on the power stroke the film of oil between the crankshaft bearing and the crankshaft gets squeezed out resulting in direct contact. Fully lubricated journal bearings generally last 'forever'

Even if you solved the above problems, some parts like springs, valve seats, and other moving parts would eventually suffer from fatigue.

Interesting calculation to make it to look at the lifetime of automotive engines in terms of hours. 200,000 miles divided by 30 mph gives a lifetime of 6600 hours. Compare with industrial electric motors and gear trains where life times of 50,000 hours are common and you can see where things are going with electric cars.

All of this is true, but in my experience, it's the rare engine that meets its end due to piston/cam friction. Usually, the engine is abandoned due to the cost of maintaining all the things attached to it (e.g., water pump, alternator, master cylinder, etc.). If you're willing to suffer the nickel and dime expenses, the actual pistons/valves/camshafts usually last many hundreds of thousands of miles.

EVs don't have as many things attached to the engine. I wonder if some "new" EVs will just be refurbished older EVs with a new battery and cosmetic changes.

People want new bodywork, seats, electronics, etc.

It might be possible to make all that replaceable, so that a car can be fully refurbished, and certainly that is done to commercial vehicles all the time (passenger buses, etc.), but not sure about the economics of doing it to light-duty cars and trucks. The body itself is probably not that expensive.

Certainly seems like it ought to be possible to pull the motors out of an old car and drop them into a new one. But then again people do that with gasoline engines all the time, too. If you blow a head gasket in a lot of cars, the "fix" is often to replace the engine with a remanufactured engine that comes out of a crate. It's cheaper to do that than to pay for the labor to actually replace the gasket in a shop, at least in a high-cost area (NE US, especially at dealers).

GM had their "skateboard" concept with the idea of swapping bodies on a general platform (it was also completely drive-by-wire).

I could see springs, but most new vehicles have hardened valve seats that don't need tretraethyl lead for lubrication.

Ferrous metals, when used in a correctly designed part, have a near infinite fatigue life.

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

Most wear is during startup before oil pressure comes up. Some aircraft engines have electric oil pumps, so that oil pressure is at 100% before the engine starts. It's common to bring up oil pressure before starting on very large Diesel engines (ships, earthmovers, tanks) to extend the life. Those usually have a starting engine to provide startup power. Large diesels are often cranked with no compression (all valves lifted) and no fuel flow to get things well lubricated before combustion starts.

Auto engines could be run that way, but the slow cold start process acceptable for heavy equipment would annoy motorists.

> Compare with industrial electric motors and gear trains where life times of 50,000 hours are common and you can see where things are going with electric cars.

To be fair, industrial engines (for generation and the like) reach 20-30k hours.

Sure, but when the engine in an old Toyota gives out, you go and find a used one that works for few hundred dollars, put that in and continue driving.

If a battery pack dies, you have no choice but to buy a new one.

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