I have a 2020 Silverado LTZ dmax that I use to pull my 26’ Gulf Stream with, last time I weighed it loaded it was ~5100lb. The truck pulls great, actually just got back from a 600 mile road trip (Houston to Fredricksburg), 400 of those were pulling in the Texas Hill Country. I got 11.5-12mpg towing with the cruise set between 65 and 70 the whole way, and I used about 1.5 gallons of DEF. I do have a small lift on my truck with upgraded Eibach/Bilstein shocks, which I highly recommend! The new shocks greatly helped with the bouncing. I did keep factory height tires (Nitto Ridge Grapplers 275/55r20), which is very important if you plan on towing, so you aren’t wasting torque trying to move a bigger tire.
Something to keep in mind is that I’m max out on GVWR with just my little trailer that has 500lb of tongue weight. Between a full tank of diesel, my family and dog, side steps, bedcover/bedmat, and tools; the truck is just maxed out payload wise. The truck feels like it could defiantly pull more than I’m towing, but I won’t be legal that’s for sure. (GVWR is 7200lb on my truck)
for reference this is my truck with a full tank of diesel and 2 passenger.