1994 Pontiac Bonneville Owner's Manual - Page 226

When to Check Check your tires oncea month or more. Don't forget your compact sparetire. It should be at 60 psi (420 kPa). How to Check Use a good quality pocket-type gage to check tire pressure. Simply looking at the tires will.not tell you the pressure, especially if you have radial tires -which may look properly inflated even if they're underinflated. X5028 Use this rotation pattern. After the tires have been rotated, adjust the front and rear inflation pressure as shown on the Tire-Loading Information label. Make certain that all wheel nuts are properly tightened. See "Wheel Nut Torque" in the Index. If your tires have valve caps, be sure to put them back on. They help prevent leaks by keeping out dirt and moisture. Tire lnspecfion and Rotafion To make your tires last longer, have them inspected and rotated at the mileages recommended in the Maintenance Schedule. See "Scheduled Maintenance Services" in the Index. e 225 ..