The new GM box is almost 6" deeper and a 1500 2WD top of the Box is now the same height as a Classc 4 X 4 HD. Ford and Dodge are a problem to fit 5th Wheels under and now GM has coppied them. I feel that the designers have done it again and copied the others without thinking of us RV owners. The only 4 x 4 short box HD trucks that could fit well under a 5th Wheel RV was the GM and now I have completrely lost confidence on getting a new model and will have to keep my 98 even longer until these designers come up with something worthwhile. Maybe they don't want us to pull 5th wheels with 4 x 4. Then the RV industry better get busy making noise about it. Whats your comments on this problem.