When It Is 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 1/16 inch
(1.6 mm) or less of tread
remaining. Some
commercial truck tires may
not have treadwear
indicators.
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 fabric showing through the
tire’s rubber.
The tread or sidewall is cracked, cut or snagged
deep enough to show cord or fabric.
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 nd out what kind and size of tires you need, look at
the Certi cation/Tire label or the Tire and Loading
Information label. SeeLoading Your Vehicle on
page 4-44for more information about these labels and
where they can be found on your vehicle.
The tires installed on your vehicle when it was new had a
Tire Performance Criteria Speci cations (TPC Spec)
number on each tire’s sidewall. When you get new tires,
GM recommends that you get tires 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, load range, traction, ride, tire
pressure monitoring system performance 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 an “MS” (for mud and snow).
Whenever you replace your tires with those not having
a TPC Spec number, make sure they are the same
size, load range, speed rating and construction
type (bias, bias-belted or radial) as your original tires.
If you replace your vehicle’s tires with those not having
a TPC Spec number, the tire pressure monitoring
system may give an inaccurate low pressure warning.
Non-TPC Spec tires may give a low pressure warning
that is higher or lower than the proper warning level you
would get with TPC Spec numbered tires.
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{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
or types (radial and bias-belted tires), the
vehicle may not handle properly, and you
could have a crash. Using tires of different
sizes may also cause damage to your vehicle.
Be sure to use the same size and type tires on
all wheels.
Your vehicle may be equipped with a different
size spare than the road tires (those originally
installed on your vehicle). When new, your
vehicle included a spare tire and wheel
assembly with a similar overall diameter as
your vehicle’s road tires and wheels, so it is all
right to drive on it. Because this spare was
developed for use on your vehicle, it will not
affect vehicle handling.
{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim anges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use only
radial-ply tires with the wheels on your vehicle.
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Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can’t know how it’s been used
or how far it’s been driven. It could fail suddenly
and cause a crash. If you have to replace a
wheel, use a new GM original equipment wheel.
Tire Chains
{CAUTION:
Do not use tire chains. There is not enough
clearance. Tire chains used on a vehicle
without the proper amount of clearance can
cause damage to the brakes, suspension or
other vehicle parts. The area damaged by the
tire chains could cause you to lose control of
your vehicle and you or others may be injured
in a crash. Use another type of traction device
only if its manufacturer recommends it for use
on your vehicle and tire size combination and
road conditions. Follow that manufacturer’s
instructions. To help avoid damage to your
vehicle, drive slowly, re-adjust or remove the
device if it is contacting your vehicle, and do
not spin your wheels. If you do nd traction
devices that will t, install them on the
rear tires.
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