My buddy has a GMC 2500 Diesel and he runs Toyo At's and gets great life out of them. He bought the truck with 39,000 miles on it and it had what appeared to be a pretty new set of them on it. He wore them out and put another set on in December of 2010 and still has decent tread on them and his truck has 133,00miles on it now. I'd say they are holding up pretty well to be on a diesel truck. They are decent tread and dont roar.