[jjav]

But you're mixing things which are regular maintenance with things which are a larger repair job.

It almost feels like you're saying the mileage a car lasts is about how many miles it can last without maintenance?

Adjusting valves (on cars that need it) is a regular maintenance item.

Cat converters, timing chains or belts are also maintenance items. Same for bushings, hoses, seals. None of these are a big deal. (Well, a few seals might be, depending on access).

Valve stems and crank bearings are a more major engine rebuild. I've never had to do this on any car even into the 200k-250k mile range. But if it is necessary, the car is back on the road after that, so it still "lasts".

[smileysteve]

> Cat converters, timing chains or belts are also maintenance items. Same for bushings, hoses, seals. None of these are a big deal.

Each of those are major service items that, at 200k miles, often individually exceed the value of the depreciated automobile at shop times * shop rate. (which, unless it's a appreciating car is ~ traditionally $2000). So most people don't change them, which leads to cascading failure. (ie timing chain costs more than the value of the car, so eventually it stretches and the valves crash)

[jjav]

Well you have a different take on "major service". If maintenance is not allowed, it is true that going past 200K gets difficult.

But if you're open to doing maintenance, the car will usually last a lot longer than that.

Timing belts are routine maintenance (60K on most cars I've had), takes me about an hour. A cat converter takes even less, four bolts (may vary by car of course).

Hoses are for the most part very easy, though occasionally there is a hose that's very inaccessible to changing it is more work. Still doable. Bushings depend on access but most I can think of have been easy. Seals vary, depending on location. Some are easy some are harder.

> exceed the value of the depreciated automobile

That's a strange criteria, why would you care?

Maintenance is not like remodeling a kitchen, you will never get your money back on resale from doing maintenance. Whether it is less, or more, than the market value of the car doesn't change anything.

All that matters is whether it is cheaper to do this maintenance on the car you own, or go buy a whole new car. In nearly every case it is cheaper to do the maintenance than to buy a new (or used) car, so makes more sense to do that.

[smileysteve]

You're on to something; old cars lasted over 200k miles just as much as new ones do, if you're willing to spend the value of the car on engine and transmission rebuilds more often. (and fight rust proactively)

Maintenance vs Value is not that strange of a criteria; it tends to be the criteria warranties (and, in case of accident, theft, or flooding: auto insurance).

But newer cars do last longer, 200k miles pretty easily for many brands (the Ecoboost head gasket and collapsing lifter issue that destroy a camshaft being the American outlier of the last decade).

Timing belt is a great example of making maintenance easier and more cost effective than a timing chain, and is one of the major factors that took automobiles from 100k to 200k miles. (Timing Chain / Timing Chain tensioner early failure was an issue on Fords for a period of time)