2015 Ram 2500 4x4 5.7 Hemi tows 11,500 lbs and does fine with my 24' V-Nose (26' total box length) enclosed, is just adequate with my 32' LQ trailer that weighs in at around 11K lbs loaded. 160K miles on it now with probably 50% miles towing and only issues I have had are with the carrier bearing in the rear cover under warranty,
The funny thing about science is that if you change one miniscule parameter you change the entire outcome to the way you want it.
