What kind of towing vehicle should I get for a 26ft bnkhs

I am not sure what year it was but a few years ago Ford built a F250 quad cab 4X4 long bed king ranch diesel that was so heavy all you could haul was 4 grown men and 500 lbs in the bed before you were over the "max" pay load for the truck.......how many really believe you were in danger if you were also pulling a 7K lb camper ? ? ?