On the one ton frame the metal is thicker and rail cross section is larger. There is really no reason to box the frame unless you are going to really abuse the truck. If your concern is load carrying, I have hauled several 2 ton loads on my 3/4 ton. Overload springs don't load until about 1.5 tons. Just distribute the load properly, and slow down when going over major obstruction.


Fred
52 3600
69 C-10