For most fitfh wheels you can pull any trailer, the upgrade in pulling is just in stronger jaws. When you get into super heavy hauler the trailer they pull is matched to the tractor then it will have a different king pin setup.

I see. I've pulled things but never had to spec one out. It was always with a company truck. I never pulled anything more than the standard 80,000 with my own truck. Oversize, but not over weight.