The question is do you want to ignore the sticker or not. From what everyone guesses, 2500s are derated to stay under the 10000 lb GVWR. For the most part, tires are the limiting factor on what you can carry in the rear on 2500 and 3500s. So, that’s (2 x tire capacity) - weight on rear.
Also, passenger vehicles tend to include the weight of the passengers in the calculation of what TC you can carry at 150 lbs for each seat being filled.
Still, if you want significant more ability to carry, you should upgrade your tires, or switch to a DRW. Upgrading the tires on a SRW won’t make it stop faster, but will significantly decrease the chance of a blowout.
Finally, search for other recent threads to get more ideas.
'10 Ford F-450, 6.4, 4.30, 4x4, 14,500 GVWR, '06 Host Rainer 950 DS, Torklift Talon tiedowns, Glow Steps, and Fastguns. Bilstein 4600s, Firestone Bags, Toyo M655 Gs, Curt front hitch, Energy Suspension bump stops.
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