I'm at 35psi on my 35s. doesn't seem to high.
my ranchos are so stiff, a bump in the road will make the rear go sideways
I drive the 35" with 38-39 psi on all 4 since long time and it seems (for me) to be the right pressure
like i said before - "proper" pressure is determined by your tires' load ratings/indices & how much weight is riding on them. if you run stock-spec tires, use the door sticker data; if you changed tire specs, then you need to do more research. a C-range 35 needs different pressure than a E-range 35; a truck with a trailer attached needs higher pressure in the rear than in the front (assuming you've loaded the trailer correctly for ~10% tongue weight).
saying "i run xx psi in my xx inch tires" is like saying "i bought Class 4 shingles for my blue house". other people with blue houses need more information to determine if Class 4 shingles are overkill for them or not.
practical example:
the factory Bridgestone Dueler A/T P265/75-16s (which are irrelevantly 31.6" tall) look to have a 114 load index & prescribe 30psi on the door sticker and are rated up to 35psi for their Standard Load construction. per published inflation charts, that 30psi spec is good for ~2400lb per tire. all's good in the world considering the front GAWR is 3050lb & the rear's 3400lb (only needing 1525f / 1700r capacity per tire before outperforming the axles)... technically a little over-inflated.
my wife's H3 is currently on Cooper Discoverer A/T3 XLT LT285/75-17s (irrelevantly 33.8" tall). these have a much heavier-duty load range E construction (being a Light Truck model) and a higher load index of 121. the inflation charts for these only publish capacities from 35-80psi, but even 35psi reads 2215lb each - still more than the axles. from there, you can plot the data & interpolate based on the trend line - then verify with a chalk test to ensure even wear once you dip below published figures.
her typical DD weight is ~5000lb (max GVWR of 6000), with a decent-enough distribution to call it 1250lb needed per corner for "normal use" & 1500lb tops. by that token, just over 25psi is all we'd ever really need, given how light duty these trucks are compared to the tires we're running. we drive at 30psi to keep the TPMS happy (because we get temperature swings of 30-50° sometimes), though it's still a little hard-riding because they're technically over-inflated for a max-loaded truck. 30psi does ride INFINITELY better than they did at 35-40psi that some shops have filled them to after doing a rotation.
that was a lot of words to highlight the bottom line of:
compare your specific tire's inflation charts to the weight that you carry to determine what pressure you should run.