1993 Buick Park Avenue Owner's Manual - Page 275

When It's Time for New Tires CAUTION: Rust or dirt on wheel, or on the parts to which a it is fastened, can make wheelnuts become loose after a time. The wheel could come off and cause an accident. When you change a wheel, remove any rust or dirt from places where the wheel attaches to the vehicle. In an emergency, you can use a cloth or a papertowel to do this; but be sure to use a scraper or wire brush later, if you need to, to get all the rust or dirt off. (See "Changing a Flat Tire" in the Index.) One way to tell when it's time fornew tires is to check the treadwear. indicators, which will appear when your tires have only 2/32 inch (1.6 mm) or less tread of remaining. You need a new tire if: YOUcan see the indicators at three places around the tire. You can see cord or fabric showingthrough the tire's rubber. 0 The tread or sidewall is cracked, cut or snagged deep enough to show cord or fabric. The tire has a bump, bulge or split. 0 273