The PSI is also tire dependent, which changes with trim and even years, so that obviously is what those tires on that GVWR vehicle require. OEM works in conjunction with tire mfrs to determine the proper PSI, just ask Firestone! You ought to see the Rebel and TRX PSI. I go lower than my sticker sometimes empty just for a better ride. There has been posted an online calculator when you change tire ratings as well.