I haven’t seen the correct procedure yet so I’m going to write the way it’s supposed to be done.
First, the replacement tires are required to provide a load capacity equal to or greater than what the OE tires provided as indicated by the certified recommended cold inflation pressures for them, depicted on the vehicle certification label.
Second, the vehicle manufacturer already accounted for the 10% decrease in load capacity for “P” tires with their recommended cold inflation pressures for the OE tires.
Third, you’ll need a load inflation chart for the replacement tires. With it you can set new recommend cold inflation pressures for the replacement tires with an inflation pressure that will meet the minimum requirements. Anything above your new recommended cold inflation pressures is optional all the way to tire sidewall max.
