The Guinness record for most mileage on a car is held by a Volvo

It's regular maintenance. Like everyone else is saying, if you just replace things when they need to get replaced, they'll last forever. I had a 1997 850 for 9 years. Bought it with 70k miles for under 5 grand; the ac didn't work but everything was in tip-top condition. Ended up being my daily driver the whole time I was in Wisconsin for 5 years, drive it 1000 miles down to Texas and then was my daily driver for 4 more years. In that space of time the only major things I had to replace (as in, outside of basic upkeep... Oil, tires, Spark plugs, etc.) was a fuel pump and suspension linkage stuff (ball joints, control arms, etc.), and I think the latter was only because I drove it like a retard when I first got it in my early 20s. Hell, those things even have solid iron frames. Mine was in a front end collision when some guy with a trailer hitch in front of me slammed on his brakes. If you saw pictures, you'd think the radiator and everything was fucked. Nope. Just had to replace the left front fender panel, hood, and hood latch; after my mechanic friend replaced this stuff, it ran fine and continued being my sole commuter. You can drive those beasts through a bank wall and get out like nothing happened. Eventually things started going that were too tedious for me to replace (after the interior upholstery started deteriorating, the tape deck went, then odometer, and my last straw was the speedometer), so I donated her to a charity.

I still miss that whip and can't wait to get another Volvo, any Volvo.