If you add things after mfg. The payload changes from sticker. Typical culprits are gooseneck or fifth wheel hitch or both. Tonneau cover. Ride Rite airbags and compressor. Nerf or step bars. Look at your trucks GVWR (most 2500s are 10000# for instance). Load up the truck as it will be for a trip (passengers, full tank gas, wife, kids, dog) and drive over to a truck stop and get a CAT scale weight ticket. Subtract that true weight from the trucks GVWR. My trucks GVWR sticker says 10000#. Sticker indicates payload 2512#. When I did the CAT my true payload is 2230#. I have added all those things I listed above and the took away almost 300# of my payload available to me for a fifth wheel pinweight.