I just got my truck, 1996 2500 6.5td, 5spd, xcab 4x4, at the end of May. The guy I bought the truck from didn't know the diff. ratio. How would I find out what mine is? I pressume it's stock because everything else was. My buddy thinks they're 3.73, but I don't have a clue. The only hint I have is that, unless I have a load on, and am stopped on a hill, I don't use 1st gear. Cheers! Brett