fwiw, my 2011 Ford F-250 SD 6.7 Diesel has a payload sticker of 2878. It is SRW, 4x2, Supercab. Only once have I wished it was 4x4. I'm to old and the truck is to heavy to get it off road. I added a set of SuperSprings and Bilsteins shocks. Expectedly, neither Supersprings nor Ford will admit to a payload increase, but while they say no, there's that accompanying wink and a nod that I'm now equal to a 1 ton. When I asked the Ford service manager if adding the overload springs would increase payload, he nodded his head up/down while saying no.
2016 Ford F-350 Lariat CC, 4x4 SRW. B&W turnover with extender. 2015 CC Silverback 29RE, fitted with Reese Goose Box. Amateur Extra Class K5TS, 2016 nights camped 16