2003 Dodge 2500 Hemi towing improvement advice

Thanks for the responses. I am running 295 tires on stock wheels, 265 are stock. The tires are 1.5" taller per tire calculator. I am towing out west on 7-8% grades. I guess the consensus is the truck should tow much beter than it does. That's what I was wondering was if others had the same experience towing with the Hemi and 3.73 gears as I do. My Cummins with 10,500 lb 5th wheel towed great, I wasn't expecting diesel towing power but 5500 lbs is light.