The tires are rated for 2,755 lbs per tire at 65 psi. Actual loaded weight is 2,320, or 870 pounds under max weight for both tires on the front. The rear is rated for 2755 X 2= 5,510 per dual or 11,020 for both rear sides. The actual loaded weight for the rear is 8,240. That is why it performs better with lower pressures.
The chart didn't go below 65 psi, so I extrapolated the weight difference per tire in 10 psi increments in the other direction. The weight increase between 65 to 75 is 285 pounds. The difference between 75 and 85 is an increase of 275 pounds. The difference between 85 and 95 is 325 pounds. Based on the foregoing, I would believe the reduction in weight carrying per tire would be less than 300 pounds per tire for a 10 psi decrease in pressure, or 55 psi. Even that would give me a 200 pound margin of safety on the front, and 1,580 in the rear. So I settled on what I believe to be 60 psi, that will leave an even greater margin of safety.
