I owned a '98 6.5 diesel in a 2500 truck. I bought it used in 2006 and for the first two years of me owning it, it was pretty good. Not too many huge repairs or anything. But then the 3rd and 4th year of ownership was more of a nightmare. I spent almost $5k in repairs one year and $3k in repairs the other. About every 3 months I had something go wrong on the truck. I sold the truck in August 2010. The good thing about the 6.5 diesels is that they are relatively cheap to work on when you compare them to duramax, cummins or powerstroke engines. It definately doesn't have tons of power. It is slow but does tow okay. Even with a fairly light load, maybe 5000#, I'd really have to get into the throttle to get up to speed. When I compare it to my new 6.0L gas truck, it is blown out of the water, the 6.0 vortec has way more power and tows better. I didn't see the fuel economy that others have posted. I seemed to get 14 mpg pretty consistantly, and that was with a mix of city and highway driving. If I did all highway, I would maybe see 16, but that would be a stretch. If you plan on doing any type of performance mods to this truck, I'd move on and get a different diesel. The 6.5's have a very limited selection of performance parts really. The best place to get performance parts is from Heath diesel, but it will cost a pretty penny to gain any amount of noticable power. Performance parts just aren't out there like they are for other diesels. I had the PMD and injector pump problems, had both replaced in 2009. I had most of the typical problems that these trucks were known for. I ended up selling the truck when it had transmission problems. Mine had maybe 140k miles on it when I sold it.