The rack, which has been the subject of previous threads, sucks on the 15. If mesa would put fenders over the wheels on the cab side, I would not have the two prominent ruts in the cab where the wheels rub. Any bumps, cracks, seams, or rocks cause the whole thing to wobble and rub. Mesa also graciously replaced the whole unit the last time I had it in to their shop because the wobble also cracked all the plastic parts in the assembly. I have a small, folding dolly that works much better for the extension cab. Oh the compression caps that keep the wheels on have failed too