[vgeek]

There are many other considerations, too. Years ago I scraped Craigslist and Autotrader, grouping cars by generation/make/model/drivetrain to be able to predict longevity based on quantity for sale versus original sales figures. If a model sold 100k per year for 10 years and only 3 were for sale in year 13, that isn't a great sign. Cheap cars will tend to have cheap owners who are more likely to skimp on maintenance, typically leading to more accrued issues and a shorter lifespan for the vehicle. Some cars are just poorly engineered, and the markets are relatively efficient in pricing resale value. The definition of "high mileage" is going to vary by who you ask. Domestics 150k, German 80k, Japanese 200k, Korean 100k. These are subjective averages (some cars like Theta engines, Darts, even late model GM 6.2s have engine failures <40k), based on when they start disappearing due to repairs being more than the vehicle is worth, but based on what I saw then and kind of observe still.

Leaning on those prior mentioned product mixes, keep in mind that Japanese manufacturers weren't in the American market 60 years ago, so market mix would be wildly different. (Multiple 400k+ mi Toyotas in my family, along with 60 year old GMs, but with aftermarket or rebuilt engines.) The cost of vehicles (and repairs) relative to prevailing wages will impact the repair vs replace balance. Trade publications like Cox/NADA/Adesa/etc. are always cited by financial blogs when mentioning consumer spending/state of economy by average age of cars on the road. Why cars get junked or totaled has shifted drastically, too. Steel bumpers were easy to replace, modern bumper covers with styrofoam backing and aluminum crumple zones, not so much. Tolerances is a vague term in that veiled PR piece on that wiki article. Machining has improved. Tech like direct injection and improved lubrication (synthetics) have done much more in terms of efficiency and longevity. In a lot of cases, manufacturers try to get more and more horsepower from the same displacement by pushing tighter engine tolerances (crank/main bearings, pistons/rings, valvetrain) and things like higher compression ratios and revs, leading to more heat and earlier failure. So while you have better initial engineering, you are closer to the point of failure. For another example, interference engines will grenade themselves if you ignore timing belt maintenance, but in the meantime, you get more horsepower by getting more air into the cylinders.

A v6 Camry or Accord is going to be have more hp, be faster,more reliable at same age, be quieter and get 3x the mpg than nearly any muscle car of the past. Unfortunately it seems that many Americans prefer giant vehicles that place more emphasis on their size (and status) than materially important factors like reliability engineering or fuel economy.

Obviously these are ancedotal examples, they can be confirmed by wasting hours reading about cars and watching mechanic review videos from people who work on them daily (I am partial to the CarCareNut on YT).