Weighing at a scale is the most accurate method, esp. if the truck was ordered with options and/or you've added anything after it left the factory. Our F250 has a lot less payload than what the door pillar stickers says but the PO ordered a bunch of options and we added a canopy/topper. Excellent truck! Way better than our old F150 and the 4.1 rear end is great for towing and accelerating. Another factor is the receiver rating it has- ours is 1250/12,500 lbs max. We tow a TT just under 7Klbs which has a tongue wt. near 1K lbs and could tow a fair bit more (TT not FW).