I have a 97 HD k2500 and want to convert to a 1 ton. The truck specs indicate the same front end weight capacity on this truck as a 97 k3500 but the rear end does not have the same capacity. I do not know if the actual housing is different or the 2500 just has lighter springs and/or frame under it. The reason I want to do this is that the highway weight restrictions are getting tougher in my part of the world and the load I am carrying requires a 1 ton (dual wheels). My truck has 3.73 gears and I am having difficulty finding a 1 ton diff. that is not 4.10. Does anyone know if 3.73 was available for these trucks? Can I install a newer diff from 2001 and newer because the Duramax equipped 1 tons are available with 3.73 gears?