When To Check; How To Check - Pontiac 2005 GTO Owner's Manual

How you load your vehicle affects vehicle handling and ride comfort. When driving with less than the maximum load
capacity allowed for your vehicle, you can set tire inflation pressure to the recommended amounts shown in the
following chart. Never load your vehicle with more weight than it was designed to carry.
Tire Size
245/45ZR17 95W
235/40ZR18 91W
T145/70R17 96M
(Compact Spare)

When to Check

Check your tires once a month or more.
Do not forget your compact spare tire. It should be at
60 psi (420 kPa). For more information about your
vehicle's compact spare tire, see Compact Spare Tire
on page 5-76.

How to Check

Use a good quality pocket-type gage to check tire
pressure. You can't tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they're underinflated.
5-60
Recommended Cold Tire Inflation
Occupant and Cargo Weight:
470 lbs (210 kg) or Less
Front Tires
30 psi (210 kPa) 30 psi (210 kPa)
33 psi (230 kPa) 33 psi (230 kPa)
60 psi (420 kPa) 60 psi (420 kPa)
Occupant and Cargo Weight:
Rear Tires Front Tires
35 psi (240 kPa)
33 psi (230 kPa)
60 psi (420 kPa)
Check the tire's inflation pressure when the tires are
cold. Cold means your vehicle has been sitting for
at least three hours or driven no more than 1 mile
(1.6 km).
Remove the valve cap from the tire valve stem. Press
the tire gage firmly onto the valve to get a pressure
measurement. If the cold tire inflation pressure matches
the recommended pressure on the Tire and Loading
Information label, no further adjustment is necessary.
If the inflation pressure is low, add air until you reach the
recommended amount.
If you overfill the tire, release air by pushing on the
metal stem in the center of the tire valve. Recheck the
tire pressure with the tire gage.
Up to 740 lbs (330 kg)
(Vehicle Capacity Weight)
Rear Tires
35 psi (240 kPa)
39 psi (270 kPa)
60 psi (420 kPa)