While the truck is rated to pull 8000#, I pulled a 5000# trailer with the same truck. it worked pretty hard, but I guess it did OK. I would have proably gone 6000#, but that would have been tops for me and still have a margin. Watch tongue weight and payload. Those are going to be your weak links, and remember, air bags will not increase the carrying capacity, they just make it level.
2011 Double Cab-Black/Black-Max Legal Window Tint-Rostra B/U Camera-ARE Bed Cover-Westin Oval Black Step Rails-Transfer Flow Fuel Tank-Extendable Tow Mirrors