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Vehicle Care 417
tires be installed on the
vehicle if frequent driving at
temperatures below
approximately 5 °C (40 °F) or
on ice or snow covered roads
is expected. See Winter Tires
0414.
Caution
High performance summer
tires have rubber
compounds that lose
flexibility and may develop
surface cracks in the tread
area at temperatures below
−7 °C (20 °F). Always store
high performance summer
tires indoors and at
temperatures above −7 °C
(20 °F) when not in use. If the
tires have been subjected to
−7 °C (20 °F) or less, let them
warm up in a heated space
to at least 5 °C (40 °F) for
24 hours or more before
being installed or driving a
vehicle on which they are
installed. Do not apply heat
(Continued)
Caution (Continued)
or blow heated air directly
on the tires. Always inspect
tires before use. See Tire
Inspection0429.
Tire Sidewall Labeling
Useful information about a
tire is molded into its
sidewall. The example
shows a typical passenger
tire sidewall.
Passenger Tire Example
(1) Tire Size:The tire size
is a combination of letters
and numbers used to
define a particular tire's
width, height, aspect ratio,
construction type, and
service description. See the
“Tire Size” illustration later
in this section.
(2) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed
to GM's specific tire
performance criteria have a
TPC specification code
molded onto the sidewall.
GM's TPC specifications
meet or exceed all federal
safety guidelines.
(3) DOT (Department of
Transportation)
:The
Department of
Transportation (DOT) code
indicates that the tire is in
compliance with the U.S.
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Vehicle Care 419
(2) Tire Width:The 3-digit
number indicates the tire
section width in millimeters
from sidewall to sidewall.
(3) Aspect Ratio
:A 2-digit
number that indicates the
tire height-to-width
measurements. For
example, if the tire size
aspect ratio is 75, as
shown in item (3) of the
illustration, it would mean
that the tire's sidewall is
75 percent as high as it
is wide.
(4) Construction Code
:A
letter code is used to
indicate the type of ply
construction in the tire. The
letter "R" means radial ply
construction; the letter "D"
means diagonal or bias ply
construction.
(5) Rim Diameter
:
Diameter of the wheel in
inches. (6) Service Description
:
These characters
represent the load index
and speed rating of the
tire. The load index
represents the load
carrying capacity a tire is
certified to carry. The
speed rating is the
maximum speed a tire is
certified to carry a load.
Tire Terminology and
Definitions
Air Pressure:The amount
of air inside the tire
pressing outward on each
square inch of the tire. Air
pressure is expressed
in kPa (kilopascal) or psi
(pounds per square inch).
Aspect Ratio
:The
relationship of a tire's
height to its width. Belt
:A rubber coated layer
of cords that is located
between the plies and the
tread. Cords may be made
from steel or other
reinforcing materials.
Bead
:The tire bead
contains steel wires
wrapped by steel cords
that hold the tire onto
the rim.
Bias Ply Tire
:A pneumatic
tire in which the plies are
laid at alternate angles less
than 90 degrees to the
centerline of the tread.
Cold Tire Pressure
:The
amount of air pressure in a
tire, measured in kPa
(kilopascal) or psi (pounds
per square inch) before a
tire has built up heat from
driving. See Tire Pressure
0 422.
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Vehicle Care 427
could damage the TPMS
sensors. See Tire Sealant and
Compressor Kit0439 for
information regarding the
inflator kit materials and
instructions.
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 light and the DIC
message should go off after
successfully completing the
sensor matching process.
See "TPMS Sensor Matching
Process" later in this section.
.One or more TPMS sensors
are missing or damaged. The
malfunction light and the DIC
message should go off when
the TPMS sensors are
installed and the sensor
matching process is
performed successfully. See
your dealer for service.
.Replacement tires or wheels
do not match the original
equipment tires or wheels. Tires and wheels other than
those recommended could
prevent the TPMS from
functioning properly. See
Buying New Tires
0432.
.Operating electronic devices
or being near facilities using
radio wave frequencies
similar to the TPMS could
cause the TPMS sensors to
malfunction.
If the TPMS is not functioning
properly it cannot detect or
signal a low tire pressure
condition. See your dealer for
service if the TPMS
malfunction light and DIC
message come on and stay on.
Tire Fill Alert (If Equipped)
This feature provides visual
and audible alerts outside the
vehicle to help when inflating
an underinflated tire to the
recommended cold tire
pressure.
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432 Vehicle Care
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 CriteriaSpecification (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
0417 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
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.
However, if it is necessary
to replace only one axle set
of worn tires, place the
new tires on the rear axle.
See Tire Rotation
0429.{Warning
Tires could explode
during improper service.
Attempting to mount or
dismount a tire could
(Continued)
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Vehicle Care 433
Warning (Continued)
cause injury or death.
Only your 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, tread
patterns, or types may
cause loss of vehicle
control, resulting in a
crash or other vehicle
damage. Use the correct
size, brand, and type of
tire on all 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 and cause a
crash. Use only radial-ply
tires with the wheels on
the vehicle.
Winter tires with the same
speed rating as the original
equipment tires may not be
available for H, V, W, Y and
ZR speed rated tires. Never
exceed the winter tires’
maximum speed capability
when using winter tires
with a lower speed rating.
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.
The Tire and Loading
Information label indicates
the original equipment tires
on the vehicle. See Vehicle
Load Limits
0255.
Different Size Tires
and Wheels
If wheels or tires are installed
that are a different size than
the original equipment wheels
and tires, vehicle performance,
including its braking, ride and
handling characteristics,
stability, and resistance to
rollover may be affected. If the
vehicle has electronic systems
such as antilock brakes,
rollover airbags, traction
control, electronic stability
control, or All-Wheel Drive, the
performance of these systems
can also be affected.
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Vehicle Care 435
well on the government
course as a tire graded
100. The relative
performance of tires
depends upon the actual
conditions of their use,
however, and may depart
significantly from the norm
due to variations in driving
habits, service practices
and differences in road
characteristics and climate.
Traction
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 tothis tire is based on
straight-ahead braking
traction tests, and does not
include acceleration,
cornering, hydroplaning,
or peak traction
characteristics.
Temperature
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 whichall 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 were
aligned and balanced at the
factory to provide the longest
tire life and best overall
performance. Adjustments to
wheel alignment and tire
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438 Vehicle Care
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 as used in a skid.
Stop pressing the accelerator
pedal and steer to straighten
the vehicle. It may be very
bumpy and noisy. Gently brake
to a stop, well off the road,
if possible.
The vehicle has no spare tire,
no tire changing equipment,
and no place to store a tire.
If the vehicle has run-flat tires,
there is no need to stop on
the side of the road to change
a flat tire. See Run-Flat Tires
0415.
If the vehicle has self-sealing
tires, see Self-Sealing Tires
0 415. Tread punctures
typically will not cause tires to
lose air. However, if the vehicle
does get a flat tire, there is no
spare tire, tire changing equipment, or place to store a
tire. Contact Roadside
Assistance for help.
{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
Special tools and
procedures are required to
service a run-flat tire.
If these special tools and
procedures are not used,
(Continued)
Warning (Continued)
injury or vehicle damage may
occur. Always be sure the
proper tools and
procedures, as described in
the service manual,
are used.
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. See Hazard Warning
Flashers 0149.
This vehicle may come with a
tire sealant and compressor
kit. To use the tire sealant and
compressor kit, see Tire
Sealant and Compressor Kit
0 439.
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Vehicle Care 449
4. Turn the ignition off. Turnoff all lights and
accessories in both
vehicles, except the hazard
warning flashers if needed.
{Warning
An electric fan can start up
even when the engine is not
running and can injure you.
Keep hands, clothing, and
tools away from any
underhood electric fan.
{Warning
Using a match near a
battery can cause battery
gas to explode. People have
been hurt doing this, and
some have been blinded.
Use a flashlight if you need
more light.
Battery fluid contains acid
that can burn you. Do not
get it on you. If you
accidentally get it in your
(Continued)
Warning (Continued)
eyes or on your skin, flush
the place with water and get
medical help immediately.
{Warning
Fans or other moving engine
parts can injure you badly.
Keep your hands away from
moving parts once the
engine is running.
5. Connect one end of the red positive (+) cable to the
remote positive (+)
terminal on the discharged
battery.
6. Connect the other end of the red positive (+) cable to
the positive (+) terminal of
the good battery.
7. Connect one end of the black negative (–) cable to
the negative (–) terminal of
the good battery. Do not let the other end
touch anything until the
next step. The other end of
the negative (–) cable does
not go to the dead battery.
It goes to a heavy,
unpainted metal
engine part.
8. Connect the other end of the black negative (–) cable
to the negative (–)
grounding point for the
discharged battery.
9. Start the engine in the vehicle with the good
battery and run the engine
at idle speed for at least
four minutes.
10. Try to start the vehicle that had the dead battery.
If it will not start after a
few tries, it probably needs
service.
Jumper Cable Removal
Reverse the sequence exactly
when removing the jumper
cables.