I've posted my story before. 1999 1500 Silverado 5.3 3.73 gears towing 24' Wanderer, no idea the actual weight but GVW was 8500, right at my max towing weight. BUT I had 3 kids and a dog in the truck plus fuel, firewood, etc.
Went through 3 transmissions.
I wouldn't pull anything besides a small camping trailer with that truck, that's my opinion. You might look at lowering the gearing, that would help some but you're really going to be pushing that 4.6, it won't like it and I'm afraid it won't live long.
