This obviously won't pertain to most shtf scenarios, but is one in and of itself, and would certainly apply for at least two other scenarios I can think of...

and it pertains to "special order" parts for your vehicle. You might want to identify them and get them while its "easy" to.

I brought my vehicle down to my mom's last Friday so my uncle and I could change a fuel pump. My uncle said "one day" at most. Lol. I'm a week in now after waiting for the pump, a steel fuel line, tracking down an o-ring for a nylon fuel line, figuring out how to repair a valve that is permanently attached to the tank, and now another steel line...

I could have purchased a second car for what I've got into parts now, and I officially hate the smell - and taste - of gasoline...

Oh well. It needed to be done I guess.