I have a '14 Ram 2500 with the 5.7 Hemi, 6 speed, 3.73 gear and is rated to tow 13k. We tow our bullet 31BHPR with it which weighs 6400lbs dry and scales at 7600lbs loaded.
It tows ok in the flats and small hills but it really struggles in the mountains. I'm not afraid to wind it out either. The killer is the 3.73 gear. We've encountered several hills where we were unable to get out of first gear when accelerating from a stop. Lots of power up to redline in first but when it would shift to second it bogged down and couldn't hold speed. Forget about accelerating. We were stuck manually shifting to hold it in first, at redline and 35mph, to the top of the hills while holding up traffic. For comparison, my old Tundra towed the same TT over the same hills effortlessly and could acclerate. Same power but 4.30 gears.
Needless to say we were a little surprised since we were barely 1/2 the tow rating. I looked at trading the truck in but would lose my shirt. Right now I'm considering a gear swap to 4.10s before next towing season.
