I bought my first diesel 3-1/2 years ago with 194,000 miles on it. Now has about 227k, it's also a plow truck, runs like a champ. High maintenance. It's a 1999 Ford 7.3 Liter F350 I have been checking these out for a while. My recommendation is to stay away from the 6.0 Fords bad design on the engines head gaskets go as the head studs get stretched under heavy load. rumor has it that they finally straightened out the mess with the 2015. That problem can be fixed with a head stud kit.
My dad puls his TT with a 2006 GMC Duramax Diesel, Crazy powerful and regular maintenance has been ok for him, it's been a solid truck he has overr 100k on it. I really like my Ford but I do all the repairs myself too to keep costs down.
Good luck!
huh this is my first post on this site. Just call me Newbie!... For now.. I'm Kevin