1995 Pontiac Trans Sport Owner's Manual - Page 305

When to Check Check yourtires once a month or more. Don't forget your compact spare tire. It should be at 60 psi (420 P a ) . Tire Inspection and Rotation Tires should be inspected every 6,000 to 8,000 miles (10 000 to 13 000 krn) for any signs of unusual wear. If unusual wear is present, rotate your tires as soon as possible and check wheel alignment. Alsocheck for damaged tires or wheels. See "When it's Time for New Tires" and "Wheel Replacement'' later in this section for more information. The purpose of regular rotation is to achievemore uniform wear for all tires on the vehicle. The first rotation is the most important. See"Scheduled 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. If your tires have valve caps, be to put them back sure on. They help preventleaks by keeping out dirt and moisture. Maintenance Services" in the Index for scheduled rotation intervals. 6-36