I'm in Tx. trying to buy a used F-250, I'm looking at 2 but the miles are very high. I've never owned a diesel so I'm not 100% confident on what to check, etc. there is a 2003 xlt crew can 4wd that's had; 2016-07-169519.10.13.jpg , all that done but not bulletproofed. 322,000 miles is a lot. I'm sure I can get the truck for $7,000 or $7,400. The other is a 2007 xlt crew cab 4wd and has about the same miles and the guy says the engine was built, studded, deleted at 270,000 miles. I can get it for around the same price. One thing is the 2003 is nearly in perfect shape and I've been told it's been in there family since new. Should I get one of these or keep looking?