I have never seen a GM half ton SUV with over 16000 pounds of payload. I'm sure some exist, but that seems more like a web site number. Looks for this sticker near the location of the one listing 7300 pounds.
6k dry is reasonable. That will likely be closer to 7500 pounds for a longer trip. You need more than suitcases of clothes. You need food, cooking/eating-ware, towels, bedding, probably some chairs for campfire, and any other recreational things.
Get a WDH with integrated sway control and proportional brake controller.
