what size tires?
tire pressure depends on how you drive the car,.how tall the sidewalls are,. how much weight you're carrying,.
a tall tire will squirm under hard cornering,.
an underinflated tire runs hot,.and deflects a lot when you hit an obstacle (pothole)
tall underinflated tires break belts,. separate belts etc,..
underinflated tires use more fuel,.
underinflated tires may wear evenly,. but they will wear faster,.
on any of my 255-50-17's i run them at 40 psi minimum,.
60psi when i,m flogging the tires on a road course,.
the minivan tires are 215-65-16,.i run them at 38,.
the fancy ford has 225-60-16's,..i run them at 40.
I run my 11X24.5's at 105.