If this helps any, got 29’ pull behind, 6465lbs, 600 on tongue, have no level kit, have sway hitch, it squats a little in back , not a lot to make difference on feel for me, I thought I might have to do same thing until I pulled it , i know you have more weight, also think I set trailer brake at 3.0 or 3.1 , also don’t forget to program trailer, it will keep memory. Was very impressed with power though especially up inclines . Also carry a bottle of def , it seems it goes pretty quick, from Nola to Dallas I filled 3 x, it went through regen mode with half a tank and all of sudden it said refill asap hope this helps
