The fastest killer of an engine is short trips. The engine never gets warm enough to burn out the acids and moisture in the oil, so it collects and starts to eat away at the bearings and everything else in the engine.
I always buy high mileage used vehicles, not so much to avoid depreciation, but because they simply don't want to sell 'bare bones' vehicles any more (base trucks with no options are typically only available in fleet numbers) So I buy older trucks/cars and strip out the AC and everything else I have no use for,and if needed convert from auto to manual trans.
I always run dino juice, that gets changed at 6000 mile intervals, filter at 3000, and they are always spotless inside, but my typical drive to work ranges from 25 miles to 200+, plenty of time to bake out the contaminants, blowby etc, and get the oil warm enough to go through the filter and not the bypass. I typically drive them for at least 10 years, and only get rid of them when I find something I like better (or when they start to rot out from the salty Michigan roads)
My current truck has 400k on it, swapped timing chain three months ago and it was still spotless inside. It runs like a top, but the body is starting to get eaten way, so if I find a good body I'll swap everything over and start again.
that baby is just getting broken in. I have a buddy in NH going for 1,000,000 miles on his Honda accord. He's at close to 800k now with original engine and transmission. Oil has been changed at the cheapest spot in town every 8k with cheap Dino oil.. Oils are much better today than they were in the past.. I generally only buy cars that have 100k or more on the clock cause I prefer to let some other person take the depreciation hit...
