YES... tires play a huge part in sway as does spongy suspension. His truck is new and would have come with E rated tires so tires should not be an issue (assuming he is towing within the limits the truck is designed for which I'm sure he is if his chev 2500 pulled it fine).Has anyone had luck correcting this with tires? I have head that tires can induce trailer sway. The fact that DRW trucks are less susceptible to trailer sway kinda leads me to think there is some truth to this. Maybe a tire with a higher load range rating would be a little stiffer?