LOL you described my truck to a "T".I had a 2007.5 Ram 3500 Quad cab dually with 6.7 Cummins and 68RFE Automatic transmission. 350 HP/680 lb Torque. Pulled everything. Never thought I'd ever give it up. Till I drove my 2019 Ram 3500 Quad cab dually with 6.7 Cummins High Output (400 hp/1000 LB Torque) and Aisin transmission with 4:10 rear end. My trailer is DRV 38RSB3 wt 18000 lbs. The Ram is rated 35000 lb towing. It has the automatic exhaust brake and dash connected EOH disc brakes on trailer (Electric over Hydraulic) It tows this trailer easily. Up the Grapevine / Tejon pass in California and up Hwy 93 from Cranbrook to Banff. All the new diesel 1 ton trucks (Ford, Chevy/GMC, Ram) are rated to tow 35000. Someone always asks me why I always buy the dually. Simple: I always have two extra spare tires where-ever I go. LOL
My build date was January 2007. Quad cab 4x2 dually 4.10 rear end. Set the cruise and forget it. Up down hills no problem.