I usually start out at 35psi and see how they wear. If they are wearing at the edges, then you need more air. If they are wearing in the center, then you need less air.
There is a method where you drive over chalk and you can see how your tire is touching the road.
How To Chalk Test Your Tires To Find Ideal Pressure for On-Road Driving - YouTube
61 II 109" Pickup (Restomod, 350 small block, TR4050)
66 IIA 88" Station Wagon (sold)
66 IIA 109" Pickup (Restomod, 5MGE, R380)
67 IIA 109" NADA Wagon (sold)
88, 2.5TD 110 RHD non-hicap pickup
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