I currently have a 2002 2500 4x4 qc that I use to haul a camper on. problem is the usual with a camper-it's too heavy for the truck. So I'm thinking about a dually 3500, but don't really want to buy 3rd gen $$$. Plus all of my extras-ride rites, pullout mirrors and torklift tie downs from the 02 will not work on 03and up. What I want to know is if there are significant diff between say 01-and 02 I think they changed the rear brakes that year midway thru but are there other upgrades between years?