1997 Buick Century Owner's Manual - Page 306

; Time for New Tires One wav to tell when it's ., time for new tires is to check the treadwear indicators, which will appear when your tires have only 1/16 inch (1.6 mm) or less of tread remaining. I The tire has a puncture, cut or other damage that can't be repaired well because of the size orlocation of the damage. Buying New Tires To find out what kind and size of tires you need, look at the Tire-Loading Information label. The tires installed on your vehicle when it was new had a TirePerformance Criteria Specification (TPC Spec) number on each tire's sidewall. When you get new tires, get ones with that same TPC Specnumber. That way your vehicle will continue to have tires that are designed to give proper endurance, handling, speed rating, traction, ride and other things during normal service on your vehicle. If your tires have an all-season tread design, the TPC number will be followedby an "MS" (for mud and snow). You need a new tire if any of the following statements are true: You can see the indicators at three or more places around the tire. You can see cord or fabricshowing through the tire's rubber. 0 The tread or sidewall is cracked, cut orsnagged deep enough to show cord or fabric. The tire has a bump, bulge or split. 0 6-40