Tires are P rates, based on the 113T listed. 113 is the load category; T is the speed. I'm not aware of any of the half tons offering LT tires for 20" wheels. 18" and smaller LT offerings for half tons, or 20" on 3/4+ tons.
Anyway, that's a good payload for a truck typically found on dealer lots. Ford quickly followed GM from 2014 by bumping the payloads.