Tire Math - Inflation vs axle ratings
Tire gurus -
I have a 2008 3500 dually. Frt GAWR = 4860lbs, 2430/ tire. RR GAWR = 8200 lbs, 2050/tire. The inflation sticker says 66lbs for the fronts, 60 for the rr.
I am running Toyo Open Country H/D Tuff Duty tires.
According to the Toyo load inflation chart -
(single) 60 psi = 2280, 65=2405, 70=2540, 75=2670, 80=2755
(dual) 60=2075, 65=2205, 70=2310, 75=2430, 80=2535
Given the above, I have run the fronts @ 70 psi. And the rears @ 60 psi. (Eases the ride when not towing and I am a bit lazy when it comes to fighting with the inside dually.)
But I read here and in other forums, and have been told more than once to inflate the rr's to 80 when towing. Why bother inflating the tires beyond the axle capacity?