Wheel Loading
Wheels are stamped with a maximum load and cold
inflation rating. Be sure you do not exceed these limits.
Dual Tire Operation
When the vehicle is new, check the wheel nut tightness
on all wheels with a torque wrench after your first
100 miles (160 km) and then 1,000 miles (1 600 km) after
that. Whenever a wheel, wheel bolt or wheel nut is
removed or serviced, repeat the 100 miles (160 km), and
then 1,000 mile (1 600 km) wheel nut tightness check.
SeeTightening the Wheel Nuts on page 5-80for wheel
nut tightening information and proper torque values.
{CAUTION:
If you operate your vehicle with a tire that is badly
underinflated, the tire can overheat. An overheated
tire can lose air suddenly or catch fire. You or
others could be injured. Be sure all tires (including
the spare, if any) are properly inflated.
SeeTires on page 5-76andInflation - Tire Pressure on
page 5-77for more information on proper tire inflation.
When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions,
influence when you need new tires.
Replace your tires when the tread depth is down to
1/8 of an inch (3.2 mm) for the front tires, or 1/16 of an
inch (1.6 mm) for a rear tire. Also, you need a new
tire if:
•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
cannot be repaired well because of the size or
location of the damage.
The rubber in tires degrades over time, even if they are
not being used. This is also true for the spare tire, if your
vehicle has one. Multiple conditions affect how fast this
aging takes place, including temperatures, loading
conditions, and inflation pressure maintenance. With
proper care and maintenance tires will typically wear out
before they degrade due to age. If you are unsure about
the need to replace your tires as they get older, consult
the tire manufacturer for more information.
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If your vehicle has four-wheel drive, the axle differentials,
propshafts, and transfer case may be damaged if tires
of different sizes, brands or tread types are installed
on the front and rear axles. That damage would not be
covered under your warranty.
Buying New Tires
GM has developed and matched specific tires for your
vehicle. If you need replacement tires, GM strongly
recommends that you get tires that are the same size,
brand, load range, speed rating, and construction type
(radial and bias-belted tires) as your vehicle’s original
tires. This way, your vehicle will continue to have tires
that are designed to give the same performance and
vehicle safety, during normal use, as the original tires.
GM recommends replacing tires in sets of six or eight as
applicable. This is because uniform tread depth on all
tires will help keep your vehicle performing most like it did
when the tires were new. Replacing less than a full set of
tires can affect the braking and handling performance of
your vehicle.
{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different
sizes, brands, or types (radial and bias-belted
tires) the vehicle may not handle properly,
and you could have a crash. Using tires of
different sizes, brands, or types may also
cause damage to your vehicle. Be sure to
use the correct size, brand, and type of tires
on your vehicle’s wheels.
{CAUTION:
If you use bias-ply tires on the vehicle, the
wheel rim flanges 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 the
vehicle.
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