My travel trailer isn't a big one, 25', 4700 lbs., 470 lb. tongue weight. Also, one of the options on this truck was the heavy duty rear springs. I pulled it once with the stock engine last summer and it did fine, just didn't have much power climbing up any hills. If I had a trailer like my best friends, 8900 lbs., I wouldn't have bought this half ton pickup for the reasons you stated. Next year, I'm going to do a TH400 changeover to seal the deal.