since I don't use tires type/size mentioned on the door jam, I use my rule
of thumb

max. pressure on the side wall minus 8psi for the FRONT

max. pressure on the side wall minus 4psi for the REAR

tintop Syncro -  General Grabber AT2 27x8.5 LT14 - FRONT: 50-8=42psi /
REAR: 50-4=46psi

if the van is heavy loaded I add 1 more psi to all tires. Really empty
(driver + passenger only) I subtract 2 more psi to all tires. I never put
in the max on the side wall, always leave some room for expansion.