I have an 03 QC 1500 with 4.7l engine. My trailer is a 33ft 6800lb fully loaded coachman ultra light. I use a hensley hitch. I plan to purchase a 6.7TD in two years when I turn 62. I pull from Arkansas to Washington State to my deep sea fishing boat yearly with this trailer however, here are my Mods: RV HD torque converter, HD kit in 545RFE trans, 4:56 gears with anti-slip, Type V hitch, Finned diff cover with temp monitor on the cover and trans pan, Firestone Air Bags, 3/4 T drive shaft with special yoke and u joints, Throttle body spacer (only lowers your peak torque RPM), and aftermarket, oversize radiator. I also added the HD fan clutch fan. Also aftermarket slotted and drilled rotors all around. Free flow magnaflow exaust converter with 70 series muffler into a 4" tail pipe. This truck has to cross three major mountain ranges each trip. The only thing is I rarely tow over 65 MPH and 60 MPH seems optimum for my set-up. Yes, I know I am pushing the limit on the truck, but I feel I have minimized the risk. I have to say, the TD Ram will be a welcome change in a few years. I once got into a 40 MPH headwind near twin falls ID. The truck wouldn't shift into third so I had to pull in second at 42 MPH until I could find a campground to wait out the wind! Other than that one instance, the truck has been a champ! Oh yes, I was supprised when I began monitoring Trans and Diff temp, that the Diff will run way hotter than the Trans when towing at 65 MPH! Monitor your temps! Good luck! Wish I had bought the Hemi on 03! One more bit of advice, I only use Casteroil Edge Synthetic oil in my 4.7l. This oil will not break down and create sludge! I change it religiously at 3k miles. Good luck and have a great day!