alright emptypockets how come we've never seen your truck around I know pretty much all the diesel guys in the area between truck pullin, drag racing and anything involving diesels and i only know one guy with a 08 twined but he lives in janesville and is efi tuned...
as far as telling by miles for trucks possibly goin bad its a crap shoot...LB7 are 01-04 and have head gasket and injector issues and are wastegated turbos...04.5-06 are LLYs starting to show headgasket issues and the injector harnesses have been known to go bad on #2 & #7...06-07 LBZ are nice motors but would probably be more then your looking to spend on a mud truck...If you go cummins get a 12 valve P-pump found in 94-98 i believe and will make good power for cheap and easy to work on as its all mechanical injection