Buick REGAL 1997 Manual page 318

When
&)s
T h e for New Tires
Rust or dirt on a wheel, or on the parts to which
it is fastened, can make wheel nuts 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 paper towel 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 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.
You need a new tire if any of the following statements
are true:
0
You can see the indicators at three or more places
around the tire.
0
You can see cord or fabric showing through the
tire's rubber.
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