I'de running 35 to 40 psi. around there somewhere, suit to your own comfort. Maybe a little more in the rear than the front if you continually carry loads.
Some people run the 4psi rule ie; 35 when cold, check when hot should be 4psi higher.
If higher you need more air to start with, if lower then a bit less.
Not a bad rule of thumb because every tyre and every 4by will be different.
Jok