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Passenger (P-Metric) Tire:A tire
used on passenger cars and some
light duty trucks and
multipurpose vehicles.
Recommended Inf lation
Pressure
:Vehicle manufacturer's
recommended tire inflation
pressure as shown on the
tire placard. See Tire Pressure
0 322 and
Vehicle Load Limits 0179.
Radial Ply Tire
:A pneumatic tire
in which the ply cords that extend
to the beads are laid at 90 degrees
to the centerline of the tread.
Rim
:A metal support for a tire
and upon which the tire beads are
seated.
Sidewall
:The portion of a tire
between the tread and the bead.
Speed Rating
:An alphanumeric
code assigned to a tire indicating
the maximum speed at which a
tire can operate. Traction
:The friction between
the tire and the road surface. The
amount of grip provided.
Tread
:The portion of a tire that
comes into contact with the road.
Treadwear Indicators
:Narrow
bands, sometimes called wear
bars, that show across the tread of
a tire when only 1.6 mm (1/16 in)
of tread remains. See When It Is
Time for New Tires 0330.
UTQGS (Uniform Tire Quality
Grading Standards)
:A tire
information system that provides
consumers with ratings for a tire's
traction, temperature, and
treadwear. Ratings are determined
by tire manufacturers using
government testing procedures.
The ratings are molded into the
sidewall of the tire. See Uniform
Tire Quality Grading 0333. Vehicle Capacity Weight
:The
number of designated seating
positions multiplied by
68 kg (150 lb) plus the rated cargo
load. See Vehicle Load Limits 0179.
Vehicle Maximum Load on the
Tire
:Load on an individual tire
due to curb weight, accessory
weight, occupant weight, and
cargo weight.
Vehicle Placard
:A label
permanently attached to a vehicle
showing the vehicle capacity
weight and the original equipment
tire size and recommended
inflation pressure. See “Tire and
Loading Information Label” under
Vehicle Load Limits 0179.
Tire Pressure
Tires need the correct amount of
air pressure to operate effectively.
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{Warning
Neither tire underinflation nor
overinflation is good.
Underinflated tires, or tires that
do not have enough air, can
result in:
.Tire overloading and
overheating which could
lead to a blowout.
.Premature or
irregular wear.
.Poor handling.
.Reduced fuel economy.
Overinflated tires, or tires that
have too much air, can result in:
.Unusual wear.
.Poor handling.
.Rough ride.
.Needless damage from
road hazards. The Tire and Loading Information
label on the vehicle indicates the
original equipment tires and the
correct cold tire inflation
pressures. The recommended
pressure is the minimum air
pressure needed to support the
vehicle's maximum load carrying
capacity. See
Vehicle Load Limits
0 179.
How the vehicle is loaded affects
vehicle handling and ride comfort.
Never load the vehicle with more
weight than it was designed to
carry.
When to Check
Check the pressure of the tires
once a month or more. Do not
forget the compact spare, if the
vehicle has one. The cold compact
spare tire pressure should be at
420 kPa (60 psi). See Compact
Spare Tire 0342. How to Check
Use a good quality pocket-type
gauge to check tire pressure.
Proper tire inflation cannot be
determined by looking at the tire.
Check the tire inflation pressure
when the tires are cold, meaning
the vehicle has not been driven for
at least three hours or no more
than 1.6 km (1 mi).
Remove the valve cap from the
tire valve stem. Press the tire
gauge firmly onto the valve to get
a pressure measurement. If the
cold tire inflation pressure
matches the recommended
pressure on the Tire and Loading
Information label, no further
adjustment is necessary. If the
inflation pressure is low, add air
until the recommended pressure is
reached. If the inflation pressure
is high, press on the metal stem in
the center of the tire valve to
release air.
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light comes on, stop as soon as
possible and inflate the tires to the
recommended pressure shown on the
Tire and Loading Information label.
SeeVehicle Load Limits 0179.
A message to check the pressure in a
specific tire displays in the Driver
Information Center (DIC). The low tire
pressure warning light and the DIC
warning message come on at each
ignition cycle until the tires are
inflated to the correct inflation
pressure. Using the DIC, tire pressure
levels can be viewed. For additional
information and details about the DIC
operation and displays see Driver
Information Center (DIC) 0132.
The low tire pressure warning light
may come on in cool weather when
the vehicle is first started, and then
turn off as the vehicle is driven. This
could be an early indicator that the air
pressure is getting low and needs to
be inflated to the proper pressure. A Tire and Loading Information label,
attached to your vehicle, shows the
size of the original equipment tires
and the correct inflation pressure for
the tires when they are cold. See
Vehicle Load Limits
0179 for an
example of the Tire and Loading
Information label and its location.
Also see Tire Pressure 0322.
The TPMS can warn about a low tire
pressure condition but it does not
replace normal tire maintenance. See
Tire Inspection 0329, Tire Rotation
0 329, and Tires0315.
Caution
Tire sealant materials are not all
the same. A non-approved tire
sealant could damage the TPMS
sensors. TPMS sensor damage
caused by using an incorrect tire
sealant is not covered by the
vehicle warranty. Always use only
the GM approved tire sealant
available through your dealer or
included in the vehicle.
TPMS Malfunction Light and
Message
The TPMS will not function properly if
one or more of the TPMS sensors are
missing or inoperable. When the
system detects a malfunction, the low
tire pressure warning light flashes for
about one minute and then stays on
for the remainder of the ignition cycle.
A DIC warning message also displays.
The malfunction light and DIC
warning message come on at each
ignition cycle until the problem is
corrected. Some of the conditions that
can cause these to come on are:
.
One of the road tires has been
replaced with the spare tire. The
spare tire does not have a TPMS
sensor. The malfunction light and
DIC message should go off after
the road tire is replaced and the
sensor matching process is
performed successfully. See “TPMS
Sensor Matching Process ”later in
this section.
. The TPMS sensor matching
process was not done or not
completed successfully after
rotating the tires. The malfunction
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If the turn signal lamp does not flash
within 15 seconds after starting to
inflate the tire, the tire fill alert has
not been activated or is not working.
If the hazard warning flashers are on,
the tire fill alert visual feedback will
not work properly.
The TPMS will not activate the tire fill
alert properly under the following
conditions:
.There is interference from an
external device or transmitter.
. The air pressure from the inflation
device is not sufficient to inflate
the tire.
. There is a malfunction in
the TPMS.
. There is a malfunction in the horn
or turn signal lamps.
. The identification code of the
TPMS sensor is not registered to
the system.
. The battery of the TPMS sensor
is low. If the tire fill alert does not operate
due to TPMS interference, move the
vehicle about 1 m (3 ft) back or
forward and try again. If the tire fill
alert feature is not working, use a tire
pressure gauge.
TPMS Sensor Matching Process
Each TPMS sensor has a unique
identification code. The identification
code needs to be matched to a new
tire/wheel position after rotating the
vehicle’s tires or replacing one or more
of the TPMS sensors. The TPMS
sensor matching process should also
be performed after replacing a spare
tire with a road tire containing the
TPMS sensor. The malfunction light
and the DIC message should go off at
the next ignition cycle. The sensors
are matched to the tire/wheel
positions, using a TPMS relearn tool,
in the following order: driver side
front tire, passenger side front tire,
passenger side rear tire, and driver
side rear tire. See your dealer for
service or to purchase a relearn tool.
A TPMS relearn tool can also be
purchased. See Tire Pressure Monitor
Sensor Activation Tool at www.gmtoolsandequipment.com or
call 1-800-GM TOOLS
(1-800-468-6657).
There are two minutes to match the
first tire/wheel position, and
five minutes overall to match all four
tire/wheel positions. If it takes longer,
the matching process stops and must
be restarted.
The TPMS sensor matching process is:
1. Set the parking brake.
2. Place the vehicle in Service Mode. See Ignition Positions
0 183.
3. Make sure the Tire Pressure info display option is turned on. The
info displays on the DIC can be
turned on and off through the
Options menu. See Driver
Information Center (DIC) 0132.
4. Use the five-way DIC control on the right side of the steering
wheel to scroll to the Tire
Pressure screen under the DIC
info page. See Driver Information
Center (DIC) 0132.
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5. Press and hold SEL in the centerof the five-way DIC control.
The horn sounds twice to signal
the receiver is in relearn mode
and the TIRE LEARNING ACTIVE
message displays on the DIC
screen.
6. Start with the driver side front tire.
7. Place the relearn tool against the tire sidewall, near the valve stem.
Then press the button to activate
the TPMS sensor. A horn chirp
confirms that the sensor
identification code has been
matched to this tire and wheel
position.
8. Proceed to the passenger side front tire, and repeat the
procedure in Step 7.
9. Proceed to the passenger side rear tire, and repeat the
procedure in Step 7.
10. Proceed to the driver side rear tire, and repeat the procedure in
Step 7. The horn sounds two
times to indicate the sensor identification code has been
matched to the driver side rear
tire, and the TPMS sensor
matching process is no longer
active. The TIRE LEARNING
ACTIVE message on the DIC
display screen goes off.
11. Turn the vehicle off.
12. Set all four tires to the recommended air pressure level
as indicated on the Tire and
Loading Information label.
Tire Inspection
We recommend that the tires,
including the spare tire, if the
vehicle has one, be inspected for
signs of wear or damage at least
once a month.
Replace the tire if:
.The indicators at three or more
places around the tire can
be seen.
.There is 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.
Tire Rotation
Tires should be rotated every
12 000 km (7,500 mi). See
Maintenance Schedule 0359.
Tires are rotated to achieve a
uniform wear for all tires. The first
rotation is the most important.
Anytime unusual wear is noticed,
rotate the tires as soon as
possible, check for proper tire
inflation pressure, and check for
damaged tires or wheels. If the
unusual wear continues after the
rotation, check the wheel
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alignment. SeeWhen It Is Time for
New Tires 0330 and
Wheel Replacement 0335.
Use this rotation pattern when
rotating the tires.
Do not include the spare tire in
the tire rotation.
Adjust the front and rear tires to
the recommended inflation
pressure on the Tire and Loading
Information label after the tires
have been rotated. See Tire
Pressure 0322 and
Vehicle Load Limits 0179. Reset the Tire Pressure Monitor
System. See
Tire Pressure Monitor
Operation 0325.
Check that all wheel nuts are
properly tightened. See “Wheel
Nut Torque ”under Capacities and
Specifications 0373, and
“Removing the Flat Tire and
Installing the Spare Tire ”under
Tire Changing 0337.
{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 a crash. When
changing a wheel, remove any rust
or dirt from places where the wheel
attaches to the vehicle. In an
emergency, a cloth or a paper towel
can be used; however, use a scraper
or wire brush later to remove all
rust or dirt.
Lightly coat the inner diameter of
the wheel hub opening with wheel
bearing grease after a wheel
change or tire rotation to prevent
corrosion or rust buildup. Do not
get grease on the wheel mounting
surface or on the wheel nuts or
bolts.
When It Is Time for New
Tires
Factors such as maintenance,
temperatures, driving speeds, vehicle
loading, and road conditions affect the
wear rate of the tires.
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Treadwear indicators are one way to
tell when it is time for new tires.
Treadwear indicators appear when the
tires have only 1.6 mm (1/16 in) or
less of tread remaining. SeeTire
Inspection 0329 and
Tire Rotation 0329.
The rubber in tires ages over time.
This also applies to the spare tire,
if the vehicle has one, even if it is
never used. Multiple factors including
temperatures, loading conditions, and
inflation pressure maintenance affect
how fast aging takes place. GM
recommends that tires, including the
spare if equipped, be replaced after six
years, regardless of tread wear. To
identify the age of a tire, use the tire
manufacture date which is the last
four digits of the DOT Tire
Identification Number (TIN) which is
molded into one side of the tire
sidewall. The first two digits represent
the week (01–52) and the last two
digits, the year. For example, the third
week of the year 2010 would have a
four-digit DOT date of 0310.Vehicle Storage
Tires age when stored normally
mounted on a parked vehicle. Park a
vehicle that will be stored for at least
a month in a cool, dry, clean area
away from direct sunlight to slow
aging. This area should be free of
grease, gasoline, or other substances
that can deteriorate rubber.
Parking for an extended period can
cause flat spots on the tires that may
result in vibrations while driving.
When storing a vehicle for at least a
month, remove the tires or raise the
vehicle to reduce the weight from the
tires.
Buying New Tires
GM has developed and matched
specific tires for the vehicle. The
original equipment tires installed
were designed to meet General
Motors Tire Performance Criteria
Specification (TPC Spec) system
rating. When replacement tires are needed, GM strongly recommends
buying tires with the same TPC
Spec rating.
GM's exclusive TPC Spec system
considers over a dozen critical
specifications that impact the
overall performance of the vehicle,
including brake system
performance, ride and handling,
traction control, and tire pressure
monitoring performance. GM's
TPC Spec number is molded onto
the tire's sidewall near the tire
size. If the tires have an all-season
tread design, the TPC Spec
number will be followed by MS for
mud and snow. See
Tire Sidewall
Labeling 0317, for additional
information.
GM recommends replacing worn
tires in complete sets of four.
Uniform tread depth on all tires
will help to maintain the
performance of the vehicle.
Braking and handling performance
may be adversely affected if all the
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tires are not replaced at the same
time. If proper rotation and
maintenance have been done, all
four tires should wear out at
about the same time. SeeTire
Rotation 0329 for information on
proper tire rotation. However, if it
is necessary to replace only one
axle set of worn tires, place the
new tires on the rear axle.
Winter tires with the same speed
rating as the original equipment
tires may not be available for H, V,
W, and ZR speed rated tires. Never
exceed the winter tire's maximum
speed capability when using
winter tires with a lower speed
rating.
{Warning
Tires could explode during
improper service. Attempting to
mount or dismount a tire could
cause injury or death. Only your
(Continued)
Warning (Continued)
dealer or authorized tire service
center should mount or
dismount the tires.
{Warning
Mixing tires of different sizes (other
than those originally installed on
the vehicle), brands, or types may
cause loss of control of the vehicle,
resulting in a crash or other vehicle
damage. Use the correct size, brand,
and type of tire on all four wheels.
{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
(Continued)
Warning (Continued)
and cause a crash. Use only
radial-ply tires with the wheels
on the vehicle.
If the vehicle tires must be
replaced with a tire that does not
have a TPC Spec number, make
sure they are the same size, load
range, speed rating, and
construction (radial) as the
original tires.
Vehicles that have a tire pressure
monitoring system could give an
inaccurate low-pressure warning if
non-TPC Spec rated tires are
installed. See Tire Pressure Monitor
Operation 0325.
The Tire and Loading Information
label indicates the original
equipment tires on the vehicle.
See Vehicle Load Limits 0179.