2008 GMC SIERRA brakes

Tire Terminology and Denitions
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.Cold Tire Pressure
:The amount of air pressure
in a tire, measured in pounds per square inch
(psi) or kilopascals (kPa) before a tire has built up
heat from driving. SeeInflation - Tire Pressure
on page 5-74.
Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant, but
without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identication Number (TIN),
an alphanumeric designator which can also identify
the tire manufacturer, production plant, brand, and
date of production.
GVWR
:Gross Vehicle Weight Rating. See
Loading Your Vehicle on page 4-36.
GAWR FRT
:Gross Axle Weight Rating for
the front axle. SeeLoading Your Vehicle
on page 4-36.
5-71

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
specic wheel and tire systems developed for
your vehicle, and have them properly installed
by a GM certied 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

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
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
CAUTION: (Continued)
CAUTION: (Continued)
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. 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.
5-90

Fuses Usage
1 Right Trailer Stop/Turn Lamp
2Electronic Suspension Control,
Automatic Level Control Exhaust
3 Left Trailer Stop/Turn Lamp
4 Engine Controls
5Engine Control Module, Throttle
Control
6 Trailer Brake Controller
Fuses Usage
7 Front Washer
8 Oxygen Sensor
9 Antilock Brakes System 2
10 Trailer Back-up Lamps
11 Driver Side Low-Beam Headlamp
12 Engine Control Module (Battery)
13Fuel Injectors, Ignition Coils
(Right Side)
14Transmission Control Module
(Battery)
15 Vehicle Back-up Lamps
16Passenger Side Low-Beam
Headlamp
17 Air Conditioning Compressor
18 Oxygen Sensors
19 Transmission Controls (Ignition)
20 Fuel Pump
21 Fuel System Control Module
22 Not Used
23 Not Used
24Fuel Injectors, Ignition Coils
(Left Side)
25 Trailer Park Lamps
26 Driver Side Park Lamps
5-127

J-Case Fuses Usage
57 Cooling Fan 1
58 Not Used
59 Heavy Duty Antilock Brake System
60 Cooling Fan 2
61 Antilock Brake System 1
62 Starter
63 Stud 2 (Trailer Brakes)
64 Left Bussed Electrical Center 1
65 Not Used
66 Heated Windshield Washer System
67 Four-Wheel Drive System
68Stud 1
(Trailer Connector Battery Power)
(Optional - 40A Fuse Required)
69 Mid-Bussed Electrical Center 1
70 Climate Control Blower
72 Not Used
73 Left Bussed Electrical Center 2Relays Usage
FAN HI Cooling Fan High Speed
FAN LO Cooling Fan Low Speed
ENG EXH VLV Not Used
FAN CNTRL Cooling Fan Control
HDLP LO/HID Low-Beam Headlamp
FOG LAMP Front Fog Lamps
A/C CMPRSR Air Conditioning Compressor
STRTR Starter
PWR/TRN Powertrain
FUEL PMP Fuel Pump
PRK LAMP Parking Lamps
REAR DEFOG Rear Defogger
RUN/CRANK Switched Power
5-129

Reporting Safety Defects to the
Canadian Government
If you live in Canada, and you believe that your vehicle
has a safety defect, notify Transport Canada
immediately, in addition to notifying General Motors of
Canada Limited. Call them at 1-800-333-0510 or write to:
Transport Canada
Road Safety Branch
2780 Sheffield Road
Ottawa, Ontario K1B 3V9
Reporting Safety Defects to General
Motors
In addition to notifying NHTSA (or Transport Canada) in
a situation like this, please notify General Motors.
Call 1-800-GMC-8782 (1-800-462-8782), or write:
GMC Customer Assistance Center
P.O. Box 33172
Detroit, MI 48232-5172
In Canada, call 1-800-263-3777 (English) or
1-800-263-7854 (French), or write:
General Motors of Canada Limited
Customer Communication Centre, CA1-163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
Service Publications Ordering
Information
Service Manuals
Service Manuals have the diagnosis and repair
information on engines, transmission, axle suspension,
brakes, electrical, steering, body, etc.
Service Bulletins
Service Bulletins’ give additional technical service
information needed to knowledgeably service General
Motors cars and trucks. Each bulletin contains
instructions to assist in the diagnosis and service
of your vehicle.
Owner Information
Owner publications are written specically for owners
and intended to provide basic operational information
about the vehicle. The owner manual includes the
Maintenance Schedule for all models.
In-Portfolio: Includes a Portfolio, Owner Manual, and
Warranty Booklet.
RETAIL SELL PRICE: $35.00 (U.S.) plus processing fee
Without Portfolio: Owner Manual only.
RETAIL SELL PRICE: $25.00 (U.S.) plus processing fee
7-15

Audio System (cont.)
Navigation/Radio System, see Navigation
Manual.................................................3-112
Radio Reception........................................3-125
Rear Seat Audio (RSA)...............................3-122
Setting the Clock.........................................3-81
Theft-Deterrent Feature...............................3-123
XM™ Satellite Radio Antenna System...........3-126
Audio System(s).............................................3-84
Automatic Headlamp System............................3-19
Automatic Transmission
Fluid..................................................5-22, 5-25
Operation...................................................2-28
Auxiliary Roof Mounted Lamp Switch.................3-20
B
Battery..........................................................5-45
Electric Power Management..........................3-22
Run-Down Protection...................................3-23
Brake
Emergencies................................................ 4-5
Brakes..........................................................5-42
System Warning Light..................................3-44
Braking........................................................... 4-3
Braking in Emergencies..................................... 4-5
Break-In, New Vehicle.....................................2-22
Bulb Replacement...........................................5-59Center High-Mounted Stoplamp (CHMSL) and
Cargo Lamp............................................5-61
Halogen Bulbs............................................5-59
Headlamp Aiming........................................5-56
Headlamps.................................................5-60
License Plate Lamps....................................5-64
Pickup Box Identication and Fender
Marker Lamps.........................................5-62
Replacement Bulbs......................................5-65
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps........................................5-62
Buying New Tires...........................................5-84
C
Calibration.............................................2-55, 2-57
California Fuel.................................................. 5-7
California Perchlorate Materials Requirements....... 5-5
California Proposition 65 Warning....................... 5-4
Canadian Owners................................................ ii
Capacities and Specications..........................5-130
Carbon Monoxide...................2-14, 2-53, 4-31, 4-55
Care of
Safety Belts..............................................5-115
Cargo Lamp...................................................3-22
Cargo Management System.............................2-78
CD, MP3 ............................................3-102, 3-106
Center Console Storage Area...........................2-76
2