It is a lariat with 20" wheels. Tires are marked max load of 3415 # (dual) or 3750 # (single) at 80 psi.
I am not sure exactly which number applies as I clearly have 2 tires (dual), but only one on each side (single), lol. They are 275/65 R20 Michelin AT2.
So, tire / wheel limit is at least 6830, axle is rated for much more. Seems like the only thing holding the truck back from having the capabilities of a SRW 1 ton is springs which I can remedy with air bags.
Rear axle weight with 4 occupants and 3/4 tank was 3350.