We have an '09 F250. I would get to the scale before making any guesses or decisions. Our actual payload is significantly less than the amount on the sticker on the door pillar which surprised me. Your limitation may not be the receiver/hitch rating but available payload cap.
We tow a TT weighing about 7K lbs and with about 950 lbs TW and are using 1200 lb spring bars. We're way below the tow capacity but don't have a lot of room left on payload cap. We have the 4.10 gears which is great for hills and acceleration.
I believe these trucks are known for a tendency to sag when loaded up. I know ours does. Great truck except I'd rather not have 4WD. Nice to have one with only 27K miles!
