I have a 2015 RAM Quad Cab ( not a Dodge
) Laramie 4X4. It has 4 corner air suspension, 3:92 posi rear end, Hemi, 8 speed tranny. Once a year my RAM, not a Dodge, tows my 28RKX Wildcat MAXX (7,600lbs empty) round trip from Iowa to Seattle and back. This trip incorporate all types of terrain, desert, mountains, and everything in between. My Ram handles the Wildcat great, going up all the inclines and going down the other side. I know I'm on the edge for hauling capacity and went with the 1500 as it's my only vehicle and it's just what I wanted for a daily driver when not towing. We also use a Blue Ox Sway Pro WDH. Hope this helps at least a little.
PS- I towed this trailer once from Seattle to iowa with my 2011 Ram Quad Cab Hemi with 3:55 rear end. The Hemi did just fine even in the mountains with the 3:55, however, the coil rear suspension was 'taxed". Rear air bags would , IMHO, be needed to safely tow a 6000lb trailer with your truck.