I figure my severe wheel hop is due to the back brakes having not been working thus heating up the fronts heavily... . and warping the rotors. I went to the parts house to order new rotors and there are two choices for the dana 60 3/4 ton truck. Does anyone know off hand which rotors I will be using ??? The book specifies a weight as well as serial # off the rotor itself. I don/t want to take off the rotors until I have the new in hand! If anyone has done this any help is appreciated. baron