Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. The vehicle
was designed and tested with top-quality brake parts.
When parts of the braking system are replaced — for
example, when the brake linings wear down and new
ones are installed — be sure to get new approved
replacement parts. If this is not done, the brakes might
not work properly. For example, if someone puts in brake
linings that are wrong for the vehicle, the balance
between the front and rear brakes can change — for the
worse. The braking performance expected can change in
many other ways if the wrong replacement brake parts
are installed.
Battery
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
This vehicle has a maintenance free battery (or batteries).
When it is time for a new battery, see your dealer/retailer
for one that has the replacement number shown on the
original battery’s label. SeeEngine Compartment
Overview on page 5-14for battery location.
Warning:Battery posts, terminals, and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.
5-43
Notice:If the other vehicle’s system is not a 12-volt
system with a negative ground, both vehicles can
be damaged. Only use vehicles with 12-volt systems
with negative grounds to jump start your vehicle.
2. If you have a vehicle with a diesel engine with two
batteries, you should know before you begin that,
especially in cold weather, you may not be able
to get enough power from a single battery in another
vehicle to start your diesel engine. If your vehicle
has more than one battery, use the battery that
is closer to the starter -- this will reduce electrical
resistance. This is located on the passenger side, in
the rear of the engine compartment.
3. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles are not touching
each other. If they are, it could cause an unwanted
ground connection. You would not be able to start
your vehicle, and the bad grounding could damage
the electrical systems.
To avoid the possibility of the vehicles rolling, set the
parking brake rmly on both vehicles involved in the
jump start procedure. Put the automatic transmission
in P (Park) or a manual transmission in Neutral
before setting the parking brake. If you have a
four-wheel-drive vehicle, be sure the transfer
case is in a drive gear, not in Neutral.Notice:If you leave the radio or other accessories
on during the jump starting procedure, they could be
damaged. The repairs would not be covered by the
warranty. Always turn off the radio and other
accessories when jump starting the vehicle.
4. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or the accessory power outlets. Turn off
the radio and all the lamps that are not needed.
This will avoid sparks and help save both batteries.
And it could save the radio!
5. Open the hood on the other vehicle and locate the
positive (+) and negative (−) terminal locations on
that vehicle.
The positive (+) terminal, is located under a red
plastic cover at the positive battery post. To uncover
the positive (+) terminal, open the red plastic cover.
5-45
(C) Aspect Ratio:A two-digit number that
indicates the tire height-to-width measurements.
For example, if the tire size aspect ratio is 75, as
shown in item C of the light truck (LT-Metric) tire
illustration, it would mean that the tire’s sidewall is
75 percent as high as it is wide.
(D) 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; and the
letter B means belted-bias ply construction.
(E) Rim Diameter
:Diameter of the wheel in
inches.
(F) Service Description
:The service description
indicates the load range and speed rating of a
tire. The load index represents the load carry
capacity a tire is certi ed to carry. The load index
can range from 1 to 279. The speed rating is
the maximum speed a tire is certi ed to carry a
load. Speed ratings range from A to Z.
Tire Terminology and De nitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
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.
5-70
The TPMS sensor matching process is outlined below:
1. Set the parking brake.
2. Turn the ignition switch to ON/RUN with the
engine off.
3. Press the Remote Keyless Entry (RKE) transmitter’s
LOCK and UNLOCK buttons at the same time for
approximately ve seconds. The horn sounds twice
to signal the receiver is in relearn mode and TIRE
LEARNING ACTIVE message displays on the DIC
screen.
If your vehicle does not have RKE, press the Driver
Information Center (DIC) vehicle information button
until the PRESS
VTO RELEARN TIRE POSITIONS
message displays. The horn sounds twice to signal
the receiver is in relearn mode and TIRE LEARNING
ACTIVE message displays on the DIC screen.
If your vehicle does not have RKE or DIC buttons,
press the trip odometer reset stem located on the
instrument panel cluster until the PRESS
VTO
RELEARN TIRE POSITIONS message displays.
The horn sounds twice to signal the receiver is in
relearn mode and TIRE LEARNING ACTIVE
message displays on the DIC screen.
4. Start with the driver side front tire.5. Remove the valve cap from the valve cap stem.
Activate the TPMS sensor by increasing or
decreasing the tire’s air pressure for ve seconds,
or until a horn chirp sounds. The horn chirp,
which may take up to 30 seconds to sound,
con rms that the sensor identi cation code has
been matched to this tire and wheel position.
6. Proceed to the passenger side front tire, and repeat
the procedure in Step 5.
7. Proceed to the passenger side rear tire, and repeat
the procedure in Step 5.
8. Proceed to the driver side rear tire, and repeat the
procedure in Step 5. The horn sounds two times to
indicate the sensor identi cation code has been
matched to the driver side rear tire, and that the
TPMS sensor matching process is no longer active.
The TIRE LEARNING ACTIVE message on the DIC
display screen goes off.
9. Turn the ignition switch to LOCK/OFF.
10. Set all four tires to the recommended air pressure
level as indicated on the Tire and Loading
Information label.
11. Put the valve caps back on the valve stems.
5-80
You need new tires if any of the following statements
are true:
You can see the indicators at three or more places
around the tire.
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 in ation 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.
Buying New Tires
GM has developed and matched speci c tires for your
vehicle. The original equipment tires installed on your
vehicle, when it was new, were designed to meet
General Motors Tire Performance Criteria Speci cation
(TPC spec) system rating. If you need replacement tires,
GM strongly recommends that you get tires with the same
TPC Spec rating. 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’s exclusive TPC Spec system considers over a
dozen critical speci cations that impact the overall
performance of your 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 a MS, for mud
and snow. SeeTire Sidewall Labeling on page 5-66
for additional information.
GM recommends replacing tires in sets of four (or six if
your vehicle has dual rear wheels). 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. See
Tire Inspection and Rotation on page 5-81for information
on proper tire rotation.
5-84
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.
{CAUTION:
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 speci c wheel and tire
systems developed for your vehicle, and have
them properly installed by a GM certi ed
technician.
SeeBuying New Tires on page 5-84andAccessories
and Modifications on page 5-4for 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.
While the tires available on General Motors
passenger cars and light trucks may vary with
respect to these grades, they must also conform
to federal safety requirements and additional
General Motors Tire Performance Criteria (TPC)
standards.
5-86
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/retailer if any of these conditions exist.
Your dealer/retailer 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.{CAUTION:
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”
underCapacities and Specifications on page 5-129.
SeeChanging a Flat Tire on page 5-92for more
information.
5-89
Used Replacement Wheels
{CAUTION:
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.
Tire Chains
{CAUTION:
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
CAUTION: (Continued)
CAUTION: (Continued)
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 nd traction devices that will t, 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.
5-90