2003 GMC SONOMA brakes

Throttle System Inspection
Inspect the throttle system for interference or binding,
and for damaged or missing parts. Replace parts
as needed. Replace any components that have high
effort or excessive wear. Do not lubricate accelerator
and cruise control cables.
Transfer Case and Front Axle
(Four-Wheel Drive) Inspection
Every 12 months or at engine oil change intervals,
check front axle and transfer case and add lubricant
when necessary. Auid loss could indicate a problem;
check and have it repaired, if needed. Check vent
hose at transfer case for kinks and proper installation.
More frequent lubrication may be required on
off-road use.
Brake System Inspection
Inspect the complete system. Inspect brake lines and
hoses for proper hook-up, binding, leaks, cracks,
chang, etc. Inspect disc brake pads for wear and rotors
for surface condition. Also inspect drum brake linings
for wear and cracks. Inspect other brake parts, including
drums, wheel cylinders, calipers, parking brake, etc.
Check parking brake adjustment. You may need to have
your brakes inspected more often if your driving
habits or conditions result in frequent braking.
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2003 - Sonoma OM

If NHTSA receives similar complaints, it may open an
investigation, and if itnds that a safety defect exists in
a group of vehicles, it may order a recall and remedy
campaign. However, NHTSA cannot become involved in
individual problems between you, your dealer or
General Motors.
To contact NHTSA, you may either call the Auto Safety
Hotline toll-free at 1-800-424-9393 (or 366-0123 in
the Washington, D.C. area) or write to:
NHTSA, U.S. Department of Transportation
Washington, D.C. 20590
You can also obtain other information about motor
vehicle safety from the hotline.
Reporting Safety Defects to the
Canadian Government
If you live in Canada, and you believe that your vehicle
has a safety defect, you should immediately notify
Transport Canada, in addition to notifying General
Motors of Canada Limited. You may write to:
Transport Canada
330 Sparks Street
Tower C
Ottawa, Ontario K1A 0N5
Reporting Safety Defects to General
Motors
In addition to notifying NHTSA (or Transport Canada)
in a situation like this, we certainly hope you’ll notify us.
Please call us at 1-800-GMC-8782 (1-800-462-8782),
or write:
Pontiac-GMC Customer Assistance Center
P.O. Box 33172
Detroit, MI 48232-5172
In Canada, please call us at 1-800-263-3777 (English)
or 1-800-263-7854 (French). Or, write:
General Motors of Canada Limited
Customer Communication Centre, 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.
RETAIL SELL PRICE: $120.00
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2003 - Sonoma OM

Audio System(s) (cont.)
Setting the Time for Radios with Radio
Data Systems (RDS)................................3-37
Setting the Time for Radios without Radio
Data Systems (RDS)................................3-36
Theft-Deterrent Feature................................3-67
Understanding Radio Reception.....................3-67
Automatic Headlamp System............................3-11
Automatic Transmission...................................2-22
Fluid..........................................................5-20
Operation...................................................2-25
Automatic Transmission Check..........................6-27
Automatic Transmission Shift Lock Control
System Check.............................................6-29
B
Backing Up....................................................4-58
Battery..........................................................5-42
Battery Replacement......................................... 2-6
Battery Rundown Protection.............................3-15
Bed Rails......................................................2-52
Before Leaving on a Long Trip.........................4-33
Before You Go Off-Roading..............................4-13
Body Lubrication Service..................................6-28
Brake
Parking......................................................2-32
System Inspection.......................................6-32Brake (cont.)
System Warning Light..................................3-27
Brake Adjustment............................................5-41
Brake Fluid....................................................5-39
Brake Pedal Travel.........................................5-41
Brake Wear...................................................5-41
Brakes..........................................................5-39
Braking........................................................... 4-5
Braking in Emergencies..................................... 4-7
Break-In, New Vehicle.....................................2-20
Bulb Replacement...........................................5-50
Center High-Mounted Stoplamp (CHMSL)........5-54
Halogen Bulbs............................................5-50
Headlamps.................................................5-50
One-Piece Front Turn Signal Lamps...............5-52
Replacement Bulbs......................................5-55
Taillamps....................................................5-55
Two-Piece Front Turn Signal Lamps...............5-53
Buying New Tires...........................................5-62
C
California Fuel.................................................. 5-5
Canada........................................................... 7-4
Canadian Owners................................................ ii
Canadian Roadside Assistance........................... 7-6
Capacities and Specifications............................5-94
Carbon Monoxide...................4-36, 4-51, 2-12, 2-37
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2003 - Sonoma OM

Top Strap Anchor Location...............................1-43
Torque Lock...................................................2-35
Total Weight on Your Vehicle’s Tires..................4-55
Towing
Recreational Vehicle.....................................4-42
Towing a Trailer..........................................4-51
Your Vehicle...............................................4-42
Trailer
Recommendations.......................................4-50
Trailer Brakes.................................................4-57
Transfer Case................................................5-48
Transfer Case and Front Axle
(Four-Wheel Drive) Inspection.......................6-32
Transmission
Fluid, Automatic...........................................5-20
Fluid, Manual..............................................5-23
Up-Shift Light..............................................3-27
Transmission Operation, Automatic....................2-25
Transmission Operation, Manual........................2-28
Transmission, Transaxle, Transfer Case Unit
Repair Manual............................................7-10
Transportation Options...................................... 7-7
Traveling to Remote Areas...............................4-15
Trip Odometer................................................3-23
Truck-Camper Loading Information....................4-48
Turn and Lane-Change Signals.......................... 3-5
Turn Signal/Multifunction Lever........................... 3-5
Turn Signals When Towing a Trailer..................4-58
Two-Piece Composite Headlamp System............5-51
Two-Tiered Loading.........................................4-48U
Underbody Flushing Service.............................6-30
Understanding Radio Reception........................3-67
Uniform Tire Quality Grading
............................5-63
United States
................................................... 7-4
Up-Shift Light
.........................................2-29, 3-27
Used Replacement Wheels
..............................5-66
Using Cleaner on Fabric
..................................5-80
Using RDS
....................................3-42, 3-50, 3-59
Using Song List Mode
.....................................3-65
Using the Recovery Hooks
...............................4-41
V
Vehicle
Control
........................................................ 4-5
Damage Warnings
........................................... iv
Loading
......................................................4-46
Parking Your
...............................................2-36
Symbols
......................................................... iv
Vehicle Identification
Number (VIN)
.............................................5-87
Service Parts Identification Label
...................5-88
Vehicle Personalization
Memory Seat
..............................................2-54
Vehicle Storage
..............................................5-42
Ventilation Adjustment
......................................3-19
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2003 - Sonoma OM