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Different Size Tires and Wheels
If you add wheels or tires that are a different size than
your original equipment wheels and tires, this could
affect the way your vehicle performs, including its
braking, ride and handling characteristics, stability, and
resistance to rollover. Additionally, if your vehicle has
electronic systems such as anti‐lock brakes, rollover
airbags, traction control, and electronic stability control,
the performance of these systems can be affected.
{WARNING:
If you add different sized wheels, your vehicle
may not provide an acceptable level of
performance and safety if tires not recommended
for those wheels are selected. You may increase
the chance that you will crash and suffer serious
injury. Only use GM specific wheel and tire
systems developed for your vehicle, and have
them properly installed by a GM certified
technician.
See Buying New Tires
on page 6‑83andAccessories
and Modificationson page 6‑4for additional
information.
Uniform Tire Quality Grading
Quality grades can be found where applicable on
the tire sidewall between tread shoulder and
maximum section width. For example:
Treadwear 200 Traction AA
Temperature A
The following information relates to the system
developed by the United States National
Highway Traffic Safety Administration (NHTSA),
which grades tires by treadwear, traction, and
temperature performance. This applies only to
vehicles sold in the United States. The grades are
molded on the sidewalls of most passenger car
tires. The Uniform Tire Quality Grading (UTQG)
system does not apply to deep tread, winter-type
snow tires, space-saver, or temporary use
spare tires, tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
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If you need to replace any of the wheels, wheel bolts,
wheel nuts or Tire Pressure Monitor System (TPMS)
sensors, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts, wheel nuts, and TPMS sensors
for the vehicle.
{WARNING:
Using the wrong replacement wheels, wheel bolts,
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make you
lose control. You could have a collision in which
you or others could be injured. Always use the
correct wheel, wheel bolts, and wheel nuts for
replacement.
Notice: The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance, and tire or tire chain
clearance to the body and chassis. Whenever a wheel, wheel bolt or wheel nut is replaced
on a dual wheel setup, check the wheel nut torque after
100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km)
of driving. For proper torque, see
“Wheel Nut Torque”
under Capacities and Specifications on page 6‑126.
See Changing a Flat Tire
on page 6‑90for more
information.
Used Replacement Wheels
{WARNING:
Putting a used wheel on the vehicle is dangerous.
You cannot know how it has been used or how far
it has been driven. It could fail suddenly and
cause a crash. If you have to replace a wheel, use
a new GM original equipment wheel.
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Tire Chains
{WARNING:
If your vehicle has dual wheels or P265/65R18,
P275/55R20 or LT265/70R17 size tires, do not
use tire chains. They can damage your vehicle
because 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, readjust, or remove the
device if it is contacting your vehicle, and do not
spin your vehicle's wheels.
If you do find traction devices that will fit, install
them on the rear tires.Notice:
If your vehicle does not have dual
wheels and has a tire size other than P265/65R18,
P275/55R20 or LT265/70R17, use tire chains only
where legal and only when you must. Use chains
that are the proper size for your tires. Install them
on the tires of the rear axle. Do not use chains on
the tires of the front axle. Tighten them as tightly as
possible with the ends securely fastened. Drive
slowly and follow the chain manufacturer's
instructions. If you can hear the chains contacting
your vehicle, stop and retighten them. If the contact
continues, slow down until it stops. Driving too fast
or spinning the wheels with chains on will damage
your vehicle.
If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your vehicle's tires properly.
If air goes out of a tire, it is much more likely to leak out
slowly. But if you should ever have a blowout, here are
a few tips about what to expect and what to do:
If a front tire fails, the flat tire creates a drag that pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
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A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you would
use in a skid. In any rear blowout remove your foot from
the accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop, well off the road if possible.
{WARNING:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without the
appropriate safety equipment and training. If a
jack is provided with the vehicle, it is designed
only for changing a flat tire. If it is used for
anything else, you or others could be badly
injured or killed if the vehicle slips off the jack. If a
jack is provided with the vehicle, only use it for
changing a flat tire.
If a tire goes flat, the next part shows how to use the
jacking equipment to change a flat tire safely.
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on the hazard
warning flashers. See Hazard Warning Flashers
on
page 4‑3.
{WARNING:
Changing a tire can be dangerous. The vehicle
can slip off the jack and roll over or fall on you or
other people. You and they could be badly injured
or even killed. Find a level place to change your
tire. To help prevent the vehicle from moving:
1. Set the parking brake firmly.
2. Put an automatic transmission shift lever in P (Park), or shift a manual transmission to
1 (First) or R (Reverse).
(Continued)
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WARNING: (Continued)
3. If you have a four-wheel-drive vehicle, be surethe transfer case is in a drive gear –not in
N (Neutral).
4. Turn off the engine and do not restart while the vehicle is raised.
5. Do not allow passengers to remain in the vehicle.
To be even more certain the vehicle will not move,
put blocks at the front and rear of the tire farthest
away from the one being changed. That would be
the tire on the other side, at the opposite end of
the vehicle. When the vehicle has a flat tire (B), use the following
example as a guide to assist you in the placement of
wheel blocks (A).
A. Wheel Block
B. Flat Tire
The following information explains how to use the jack
and change a tire.
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Make sure that the jack head is positioned so that
the rear axle is resting securely between the
grooves that are on the jack head.
{WARNING:
Getting under a vehicle when it is jacked up is
dangerous. If the vehicle slips off the jack, you
could be badly injured or killed. Never get under a
vehicle when it is supported only by a jack.
{WARNING:
Raising your vehicle with the jack improperly
positioned can damage the vehicle and even
make the vehicle fall. To help avoid personal
injury and vehicle damage, be sure to fit the
jack lift head into the proper location before
raising the vehicle.
6. Turn the wheel wrench clockwise to raise the vehicle. Raise the vehicle far enough off the
ground so there is enough room for the spare tire
to fit under the wheel well.
7. Remove all the wheelnuts and take off the
flat tire.
{WARNING:
Rust or dirt on a wheel, or on the parts to which it
is fastened, can make wheel nuts become loose
after time. The wheel could come off and cause
an accident. When changing a wheel, remove any
rust or dirt from places where the wheel attaches
to the vehicle. In an emergency, use a cloth or a
paper towel to do this; but be sure to use a
scraper or wire brush later, if needed, to get all the
rust or dirt off. See Changing a Flat Tire
on
page 6‑90
.
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8. Remove any rust or dirtfrom the wheel bolts,
mounting surfaces, and
spare wheel.
9. Install the spare tire.
{WARNING:
Never use oil or grease on bolts or nuts because
the nuts might come loose. The vehicle's wheel
could fall off, causing a crash.
10. Put the wheel nuts back on with the rounded end of the nuts toward the wheel.
11. Tighten each wheel nut by hand. Then use the wheel wrench to tighten the nuts until the wheel is
held against the hub.
12. Turn the wheel wrench counterclockwise to lower the vehicle. Lower the jack completely.
{WARNING:
If wheel studs are damaged, they can break. If all
the studs on a wheel broke, the wheel could come
off and cause a crash. If any stud is damaged
because of a loose-running wheel, it could be that
all of the studs are damaged. To be sure, replace
all studs on the wheel. If the stud holes in a wheel
have become larger, the wheel could collapse in
operation. Replace any wheel if its stud holes
have become larger or distorted in any way.
Inspect hubs and hub‐piloted wheels for damage.
Because of loose running wheels, piloting pad
damage may occur and require replacement of
the entire hub, for proper centering of the wheels.
When replacing studs, hubs, wheel nuts or
wheels, be sure to use GM original equipment
parts.
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{WARNING:
Wheel nuts that are improperly or incorrectly
tightened can cause the wheels to become loose
or come off. The wheel nuts should be tightened
with a torque wrench to the proper torque
specification after replacing. Follow the torque
specification supplied by the aftermarket
manufacturer when using accessory locking wheel
nuts. SeeCapacities and Specifications
on
page 6‑126
for original equipment wheel nut
torque specifications.
Notice: Improperly tightened wheel nuts can lead
to brake pulsation and rotor damage. To avoid
expensive brake repairs, evenly tighten the wheel
nuts in the proper sequence and to the proper
torque specification. See Capacities and
Specifications
on page 6‑126for the wheel nut
torque specification.
13. Tighten the nuts firmly in a crisscross sequence as
shown by turning the wheel wrench clockwise.
Have a technician check the wheel nut tightness of all
wheels with a torque wrench after the first 100 miles
(160 km) and then 1,000 miles (1600 km) after that.
Repeat this service whenever you have a tire removed
or serviced. See Capacities and Specifications
on
page 6‑126for more information.
When you reinstall the regular wheel and tire, you
must also reinstall either the center cap, or bolt-on hub
cap, depending on what your vehicle is equipped with.
6-102