Greetings! I did a little thread necromancy in regards to the F250 vs F350 discussions going on, specifically in regards to 5th wheel towing. It hits right in my wheelhouse as I have a 2011 F250 6.7 Lariat 4x4 crew cab with a measly 2k payload "rating". I had already started my spreadsheet when I came across yours in another thread and I had a question.
I have the same 20" wheels on my 2011 and accounted for load in the same way. However I was curious as to how you came up with your 9750 axle rating? Was it based on the published F350 rear axle rating for the 10.5 Sterling?
Bottom line, I'm thinking a a 7k wheel limited rating minus whatever my loaded rear axle weight ends up being is probably how I'll base my payload as well.
I've always heard the rumors about 3/4 to 1 ton truck differences and I did a little of this research for my father's 2500 Ram. Nice to see I'm not the only OCD researcher out there

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