I had an 2000 Chevy 1500 with the 5.3'and 3.42 gears with the old 4 speed. At that time I was pulling a small 24 footer 5th wheel around 6500lbs. I had no issues with it, sure it was slower in Georgia mountains but overall a good truck. That being said I would not have wanted to go any heavier then that with the truck. Now it appears that u have an 08 so u should have the 6 speed and since a 4x4, u may have the 3:73 or at least 3:42. So your truck should do better since it has more HP and TQ plus the 6 speed auto. Good luck with your purchase.
Kris
