Hi, I know exactly what you are going through. We had a 2005 granite ridge on a 450 chassis.I put new shocks , tires and had the front end aligned at a local shop and it was still a white knuckle experience to drive. I went on this forum and some good people gave me the camber and caster settings for the class c with the 450 chassis.My local shop would not set up the unit with the settings i was given so i found a truck alignment shop and they set the unit up with the new settings. The unit drove like a new car. The shop that did the work said they wish they had these settings before because there were a lot of people with class c units that have the same problem. I cant remember the settings now but i`m sure someone on this forum can tell you. Good luck