@dutiful don, That 82psi is only applicable for the OEM tires, the Goodyear G670. So ignore that now on since your using some Michelins.
Get your rig weighed out at a truck stop. Most say to get a 4 corner weigh, but I've only used the axle scales at the truck stops. You'll find out that the 30DS is close to your axle rating in the rear if not over. And your steers have room to spare. Once you get the weight ticket from the scales, take a look at the loading chart here.
I'm guessing for the XZE, the lowest PSI listed is 75psi, which is the lowest you can go regardless of your weights. With the Goodyears, it was 80 psi. Enjoy your new kicks.
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