I live in the rust belt, where the average life expectancy of a car is about 10 years. 12-15 if you _really_ baby it. Except for one car that was totaled (got rear-ended by a texter), all of the cars I no longer own succumbed to a rotted out frame. Engines were fine, bodies were fine, interiors were fine.

But a frame. Can't really replace a frame. You can _sometimes_ repair it. You can buy some time by paying for an oil-based undercoating every year, but finding someone who will do it affordably _and_ do a good job is hard. (It's a messy, annoying job.)

I sort of want congress to mandate stainless steel or aluminum frames in all cars sold in the US, and I don't even care if it makes the cars cost more. It won't happen via state laws because the auto manufacturers are big campaign donors around here.