I have 40 max psi on my tires what psi should I have in them
Open the drivers door and on the door jamb there will be a plaque that lists what the tire pressure should be . Or any tire shop will answer this for you .
Most passenger cars take 32psi but it’s always best to follow @VOLVO_V70 's advice for your specific vehicle.
Just remember that the pressure is measured “cold”, before driving your car, typically first thing in the morning.
No, you don’t!
The max pressure will be one of the following: 35, 36, 41, 44, 50, or 51. Long story why that is so. (Barry’s Tire Tech: Load Tables)
The 40 psi is a warning not to exceed this value when seating the beads. That’s not the max usage pressure.