Comment Re: Life Expectancy Study. (Score 1) 104
Timing chains and head gaskets are an integral part of the engine so the lifetime of an engine is also the lifetime of those.
Timing *chains* are not universal, but they do help. Timing belts are quite common. Headgaskets still go and are still a massive labor cost. Within the last couple of years I've had to pay for timing belt change, a new radiator, new hoses due to leaks, a new evap canister, a new alternator. This is on a 2015. I'm told I'm "lucky" the turbo hasn't keeled over on me as this model is notorious for turbo issues. My colleague has had to pay for *two* headgaskets on a 2017 in the last few years. These aren't "solved" problems because it's pretty fundamental physics. Some things are more solved, e.g. I would have had to pay money probably for power steering problems, but the switch to electric power steering pumps greatly helps.
I have personally never heard of a timing belt failing.
Because it's preventative maintenance and if you have one, you are expected to change it every 100,000 miles. Since we have interference engines, you don't want to push your luck since a failed timing belt will ruin the engine.