I have an 08 H.Q.C. I don`t use it everyday but use it to tow and get around when it snows, It is washed as soon as possible after being driven in the snow. A friend showed me something: In the rear wheel wells up against the outside of the truck there is an inner fender that has three big oval shaped holes that the moisture and crud can get in, I think this is why so many trucks like mine and older are rotting the moisture is getting in there and is getting trapped: I filled the holes real good with silicone sealer, hopefully this helps keep the moisture and crud out.