I too am REALLY curious about the 8 speed transmission comment. Mine performs excellently towing or not. My trailer is about 6500 lbs and only 24 feet long, but it tows like a dream behind my 2015 Ram 1500, regardless of terrain. No sway at all. I agree the rear springs are soft. I added Timbrens and absolutely hated them. Constantly bouncing off the bump stops is not a pleasant experience for a long tow. I would rather have the sag. Since then, I've upgraded to progressive heavy duty rear springs. My next trailer will be close to 30 feet, but not over.
