Chevrolet 1994 Blazer Owner's Manual page 281

When lt's Time
for
New Tires
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 2/32 inch
(1.6 mm) or less of
tread remaining.
You need a new tire if
0
You can see the indicators at three or more places around the tire.
You can see cord or fabric showing through the tire's rubber.
The tread or sidewall is cracked, cut or snagged deep enough to show
cord or fabric.
0
The tire has a bump, bulge or split.
The tire has a puncture, cut, or other damage that can't be repaired well
because of the size or location of the damage.
Buying New Tires
To find out what kind and size of tires you need, look at the
CertificatiodTire label.
The tires installed
on
your vehicle when it was new had a Tire Performance
Criteria Specification (TPC Spec) number on each tire's sidewall. When you
get new tires, get ones with that same TPC Spec number. 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 followed by a "MS" (for mud and snow).
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