Black plate (76,1)GMC Sierra Owner Manual - 2011
10-76 Vehicle Care
The outer tire on a dual wheel
setup generally wears faster than
the inner tire. Your tires will wear
more evenly and last longer if you
rotate the tires periodically, seeTire
Inspection on page 10‑73 andTire
Rotation on page 10‑73. Also see
Scheduled Maintenance on
page 11‑2.
{WARNING
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) are properly inflated.
See Tire Pressure on page 10‑66,
for 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.
One way to tell when it is time for
new tires is to check the treadwear
indicators, which appear when the tires have only 1.6 mm (1/16 in)
or less of tread remaining.
Some commercial truck tires may
not have treadwear indicators.
See
Tire Inspection on page 10‑73
and Tire Rotation on page 10‑73
for additional information.
The rubber in tires ages over time.
This is also true for the spare tire,
if the vehicle has one, even if it is
not being used. Multiple conditions
affect how fast this aging takes
place, including temperatures,
loading conditions, and inflation
pressure maintenance. Tires will
typically need to be replaced due to
wear before they may need to be
replaced due to age. Consult the tire
manufacturer for more information
on when tires should be replaced.
Black plate (78,1)GMC Sierra Owner Manual - 2011
10-78 Vehicle Care
GM recommends replacing tires in
sets of four. This is because uniform
tread depth on all tires will help
keep the 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 the vehicle.
SeeTire Inspection on page 10‑73
and Tire Rotation on page 10‑73 for
information on proper tire rotation.
{WARNING
Tires could explode during
improper service. Attempting to
mount or dismount a tire could
cause injury or death. Only your
dealer or authorized tire service
center should mount or dismount
the tires.
{WARNING
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
might not handle properly, and
you could have a crash. Using
tires of different sizes, brands,
or types could also cause
damage to the vehicle. Be sure
to use the same size, brand,
and type of tires on all wheels.
This vehicle may have a different
size spare than the road tires
(those originally installed on the
vehicle). When new, the vehicle
included a spare tire and wheel
assembly with a similar overall
diameter as the vehicle's road
tires and wheels, so it is all right
to drive on it. Because this spare
was developed for use on the
vehicle, it will not affect vehicle
handling.
{WARNING
Using bias-ply tires on the
vehicle may cause the wheel
rim flanges to develop cracks
after many miles of driving.
A tire and/or wheel could fail
suddenly and cause a crash.
Use only radial-ply tires with
the wheels on the vehicle.
If you must replace the vehicle's
tires with those that do not have
a TPC Spec number, make sure
they are the same size, load range,
speed rating, and construction type
(radial and bias‐belted tires) as the
vehicle's original tires.
Black plate (79,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-79
Vehicles that have a tire pressure
monitoring system may give an
inaccurate low‐pressure warning
if non‐TPC Spec-rated tires are
installed on the vehicle. Non‐TPC
Spec-rated tires may give a
low‐pressure warning that is
higher or lower than the proper
warning level you would get with
TPC Spec-rated tires. SeeTire
Pressure Monitor System on
page 10‑68.
The vehicle's original equipment
tires are listed on the Tire and
Loading Information label. See
Vehicle Load Limits on page 9‑25
for more information about the Tire
and Loading Information label and
its location on the vehicle.Different Size Tires and
Wheels
If you add wheels or tires that are
a different size than the original
equipment wheels and tires, this
could affect the way the vehicle
performs, including its braking,
ride and handling characteristics,
stability, and resistance to rollover.
Additionally, if the vehicle has
electronic systems such as antilock
brakes, rollover airbags, traction
control, and electronic stability
control, the performance of these
systems can be affected.
{WARNING
If different sized wheels are used,
there may not be an acceptable
level of performance and safety
if tires not recommended for
those wheels are selected.
This increases the chance
of a crash and serious injury.
Only use GM specific wheel
and tire systems developed
for the vehicle, and have them
properly installed by a GM
certified technician.
See Buying New Tires on
page 10‑77 andAccessories
and Modifications on page 10‑3
for additional information.
Black plate (81,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-81
Traction–AA, A, B, C
The traction grades, from
highest to lowest, are AA, A, B,
and C. Those grades represent
the tire's ability to stop on
wet pavement as measured
under controlled conditions
on specified government
test surfaces of asphalt and
concrete. A tire marked C may
have poor traction performance.
Warning: The traction grade
assigned to this tire is based
on straight-ahead braking
traction tests, and does not
include acceleration, cornering,
hydroplaning, or peak traction
characteristics.
Temperature –A, B, C
The temperature grades
are A (the highest), B, and C,
representing the tire's resistance
to the generation of heat and its
ability to dissipate heat when tested under controlled
conditions on a specified
indoor laboratory test wheel.
Sustained high temperature can
cause the material of the tire to
degenerate and reduce tire life,
and excessive temperature
can lead to sudden tire failure.
The grade C corresponds to a
level of performance which all
passenger car tires must meet
under the Federal Motor Safety
Standard No. 109. Grades B
and A represent higher levels of
performance on the laboratory
test wheel than the minimum
required by law. Warning: The
temperature grade for this tire
is established for a tire that
is properly inflated and not
overloaded. Excessive speed,
underinflation, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.Wheel Alignment and Tire
Balance
The tires and wheels on the vehicle
were aligned and balanced carefully
at the factory to give the longest tire
life and best overall performance.
Adjustments to wheel alignment and
tire balancing will not be necessary
on a regular basis. However, if there
is unusual tire wear or the vehicle
pulls to one side or the other, the
alignment should be checked. If the
vehicle vibrates when driving on a
smooth road, the tires and wheels
might need to be rebalanced. See
your dealer for proper diagnosis.
Black plate (82,1)GMC Sierra Owner Manual - 2011
10-82 Vehicle Care
Wheel Replacement
Replace any wheel that is bent,
cracked, or badly rusted or
corroded. If wheel nuts keep coming
loose, the wheel, wheel bolts and
wheel nuts should be replaced.
If the wheel leaks air, replace it
(except some aluminum wheels,
which can sometimes be repaired).
See your dealer if any of these
conditions exist.
Your dealer will know the kind of
wheel you need.
Each new wheel should have
the same load-carrying capacity,
diameter, width, offset and be
mounted the same way as the
one it replaces.
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 can be dangerous. It could
affect the braking and handling
of the vehicle. Tires can lose air,
and cause loss of control, causing
a crash. 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
160, 1 600 and 10 000 km
(100, 1,000 and 6,000 miles)
of driving. For proper torque,
see
“Wheel Nut Torque” under
Capacities and Specifications on
page 12‑2.
See If a Tire Goes Flat on
page 10‑84 for more information.
Used Replacement Wheels
{WARNING
Replacing a wheel with a used
one is dangerous. How it has
been used or how far it has been
driven may be unknown. It could
fail suddenly and cause a crash.
When replacing wheels, use a
new GM original equipment
wheel.
Black plate (83,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-83
Tire Chains
{WARNING
If the vehicle has dual wheels
or P265/65R18, P275/55R20,
LT265/70R17, LT265/70R18,
LT265/60R20, P285/50R20,
P285/45R22 or 285/45R22 size
tires, do not use tire chains.
They can damage the 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 the vehicle and
you or others may be injured in
a crash.(Continued)
WARNING (Continued)
Use another type of traction
device only if its manufacturer
recommends it for use on the
vehicle and tire size combination
and road conditions. Follow
that manufacturer's instructions.
To help avoid damage to the
vehicle, drive slowly, readjust,
or remove the device if it is
contacting the vehicle, and do
not spin the vehicle's wheels.
If you do find traction devices that
will fit, install them on the rear
tires. Notice:
If the vehicle does not
have dual wheels and has a
tire size other than P265/65R18,
P275/55R20, LT265/70R17, LT265/
70R18, LT265/60R20, P285/50R20,
P285/45R22, or 285/45R22, use
tire chains only where legal and
only when you must. Use chains
that are the proper size for the
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 the 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 the vehicle.
Black plate (84,1)GMC Sierra Owner Manual - 2011
10-84 Vehicle Care
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 off the
road, if possible.
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 theaccelerator 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
Driving on a flat tire will cause
permanent damage to the tire.
Re-inflating a tire after it has
been driven on while severely
underinflated or flat may cause
a blowout and a serious crash.
Never attempt to re-inflate a tire
that has been driven on while
severely underinflated or flat.
Have your dealer or an authorized
tire service center repair or
replace the flat tire as soon
as 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.
Black plate (85,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-85
If a tire goes flat, avoid further tire
and wheel damage by driving slowly
to a level place, well off the road,
if possible. Turn on the hazard
warning flashers. SeeHazard
Warning Flashers on page 6‑5.
{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)
WARNING (Continued)
3. If you have afour-wheel-drive vehicle,
be sure the 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.