Got E rated tires installed, 80psi max, Tire guy said it would be better to run around 65-70 psi as tires heat up. Always thought I should run max cold rating 80psi. FW weight is around 9000 lbs hooke...
Just be aware that lowering pressure below sidewall lowers the load rating. An E rated tire at 65 psi has the same load rating as a D rated tire. So my question would be, why upgrade tires if you aren't going to take advantage of the increased load capacity and safety margin that goes with it? I would start at max and work my way down if wear is uneven but your tires will probably be age limited before they run out of tread.