Fuse Usage
44 Left Headlamp - High Beam
45 Right Headlamp - High Beam
46Truck Body Controller- Accessory
(Gas), Truck Body Controller,
Transmission Control Module
Accessory (Diesel)
47 Front Windshield Wiper
48Anti-lock Brakes, Vehicle Stability
Enhancement System
49 Ignition A
50 Trailer
51 Climate Control Blower
52 Ignition B
63Spare (Gas), Engine Control Module
Actuator (Diesel)
64 SpareRelays Usage
53 Windshield Wiper
54 Air Conditioning
55Spare (Gas), Rear Fog Lamps
(Diesel)
56 Headlamp - High Beam
57 Fuel Pump
58 Headlamp - Low Beam
59 Horn
SPARE (G),
ECM (D)Spare (Gas), Engine Control
Module (Diesel)
STRTR Starter
Circuit Breaker Usage
PWR SEAT Power Seat
5-97
MaintenanceI— Use MaintenanceIif the change
engine oil light comes on within 10 months since
the vehicle was purchased or MaintenanceIIwas
performed.MaintenanceII— Use MaintenanceIIif the previous
service performed was MaintenanceI. Always use
MaintenanceIIwhenever the message comes on
10 months or more since the last service or if the
message has not come on at all for one year.
Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and filter. SeeEngine Oil (Gasoline Engine) on page 5-13.
Reset oil life system. SeeEngine Oil Life System (Gasoline Engine) on
page 5-16.An Emission Control Service.••
Lubricate chassis components.See footnote #.••
Visually check for any leaks or damage.See footnote (j).••
Inspect engine air cleaner filter. If necessary, replace filter. SeeEngine Air
Cleaner/Filter on page 5-17.See footnote (l).•
Rotate tires and check inflation pressures and wear. SeeTire Inspection
and Rotation on page 5-61and “Tire Wear Inspection” inAt Least Once a
Month on page 6-10.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer fluid levels and add
fluid as needed.••
Perform any needed additional services. See “Additional Required
Services” in this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
6-5
Maintenance Footnotes
(Gasoline Engine)
This maintenance section applies to vehicles with a
gasoline engine. If your vehicle has a diesel engine, see
the maintenance schedule section in the DURAMAX
®
Diesel Engine Supplement.
†The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle’s useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.
#Lubricate the front suspension, kingpin bushings,
steering linkage, and rear driveline center splines.
(a)Visually inspect brake lines and hoses for proper
hook-up, binding, leaks, cracks, cha ng, etc. Inspect
disc brake pads for wear and rotors for surface
condition. Inspect other brake parts, including calipers,
parking brake, etc.
(b)Visually inspect front and rear suspension and
steering system for damaged, loose, or missing parts,
signs of wear, or lack of lubrication. Inspect power
steering lines and hoses for proper hook-up, binding,
leaks, cracks, cha ng, etc.(c)Visually inspect hoses and have them replaced if they
are cracked, swollen, or deteriorated. Inspect all pipes,
ttings, and clamps; replace with genuine GM parts as
needed. To help ensure proper operation, a pressure test
of the cooling system and pressure cap and cleaning the
outside of the radiator and air conditioning condenser is
recommended at least once a year.
(d)Visually inspect wiper blades for wear or cracking.
Replace wiper blades that appear worn or damaged
or that streak or miss areas of the windshield.
(e)Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors, and anchorages
are working properly. Look for any other loose or
damaged safety belt system parts. If you see anything
that might keep a safety belt system from doing its
job, have it repaired. Have any torn or frayed safety belts
replaced. Also look for any opened or broken airbag
coverings, and have them repaired or replaced.
The airbag system does not need regular maintenance.
(f)Lubricate all key lock cylinders, hood hinges, hood
prop rod pivot, hood latch assembly, secondary
latch, pivots, spring anchor, release pawl, rear
compartment hinges, latches, locks, fuel door hinge,
and any moving seat hardware. More frequent
lubrication may be required when exposed to a corrosive
environment. Applying silicone grease on weatherstrips
with a clean cloth will make them last longer, seal
better, and not stick or squeak.
6-8
At Least Once a Year
Starter Switch Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. SeeParking Brake on page 2-23.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The vehicle
should start only in PARK (P) or NEUTRAL (N). If
the vehicle starts in any other position, contact your
GM Goodwrench
®dealer for service.
Automatic Transmission Shift Lock
Control System Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle. It should be parked on a level
surface.
2. Firmly apply the parking brake. SeeParking Brake
on page 2-23.
Be ready to apply the regular brake immediately if
the vehicle begins to move.
3. With the engine off, turn the ignition to RUN, but do
not start the engine. Without applying the regular
brake, try to move the shift lever out of PARK (P)
with normal effort. If the shift lever moves out
of PARK (P), contact your GM Goodwrench
®dealer
for service.
6-11
Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn
the ignition to LOCK in each shift lever position.
•The ignition should turn to LOCK only when the
shift lever is in PARK (P).
•The key should come out only in LOCK.
Contact your GM Goodwrench
®dealer if service is
required.
Parking Brake and Automatic
Transmission Park (P) Mechanism Check
{CAUTION:
When you are doing this check, your vehicle
could begin to move. You or others could be
injured and property could be damaged. Make
sure there is room in front of your vehicle in
case it begins to roll. Be ready to apply the
regular brake at once should the vehicle begin
to move.Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular brake, set the
parking brake.
•To check the parking brake’s holding ability: With
the engine running and transmission in
NEUTRAL (N), slowly remove foot pressure from
the regular brake pedal. Do this until the vehicle is
held by the parking brake only.
•To check the PARK (P) mechanism’s holding ability:
With the engine running, shift to PARK (P).
Then release the parking brake followed by the
regular brake.
Contact your GM Goodwrench
®dealer if service is
required.
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
6-12
Recommended Fluids and
Lubricants (Gasoline Engine)
This maintenance section applies to vehicles with a
gasoline engine. If your vehicle has a diesel engine, see
the maintenance schedule section in the DURAMAX
®
Diesel Engine Supplement.
Fluids and lubricants identified below by name, part
number, or specification may be obtained from
your dealer.
Usage Fluid/Lubricant
Engine OilEngine oil which meets GM
Standard GM6094M and displays
the American Petroleum Institute
Certified for Gasoline Engines
starburst symbol. GM Goodwrench
®
oil meets all the requirements for
your vehicle. To determine the
proper viscosity for your vehicle’s
engine, seeEngine Oil (Gasoline
Engine) on page 5-13.
Engine Coolant50/50 mixture of clean, drinkable
water and use only DEX-COOL
®
Coolant. SeeEngine Coolant on
page 5-21.
Usage Fluid/Lubricant
Hydraulic Brake
SystemDelco®Supreme 11 Brake Fluid or
equivalent DOT-3 brake fluid.
Windshield
WasherGM Optikleen
®Washer Solvent.
Parking Brake
Cable GuidesChassis Lubricant (GM Part No.
U.S. 12377985, in Canada
88901242) or lubricant meeting
requirements of NLGI #2, Category
LB or GC-LB.
Power Steering
SystemGM Power Steering Fluid (GM Part
No. U.S. 89021184, in Canada
89021186).
Automatic
TransmissionDEXRON
®-VI Automatic
Transmission Fluid.
Key Lock
CylindersMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241, in
Canada 10953474).
Chassis
LubricationChassis Lubricant (GM Part No.
U.S. 12377985, in Canada
88901242) or lubricant meeting
requirements of NLGI #2, Category
LB or GC-LB.
Front Wheel
BearingsWheel bearing lubricant meeting
requirements of NLGI #2, Category
GC or GC-LB (GM Part No. U.S.
1051344, in Canada 993037).
6-13
Vehicle Data Collection and Event
Data Recorders
Your vehicle, like other modern motor vehicles, has a
number of sophisticated computer systems that monitor
and control several aspects of the vehicle’s performance.
Your vehicle uses on-board vehicle computers to monitor
emission control components to optimize fuel economy,
to monitor conditions for airbag deployment and, if so
equipped, to provide anti-lock braking and to help the
driver control the vehicle in difficult driving situations.
Some information may be stored during regular
operations to facilitate repair of detected malfunctions;
other information is stored only in a crash event by
computer systems, such as those commonly called
event data recorders (EDR).
In a crash event, computer systems, such as the Airbag
Sensing and Diagnostic Module (SDM) in your vehicle
may record information about the condition of the vehicle
and how it was operated, such as data related to
engine speed, brake application, throttle position, vehicle
speed, safety belt usage, airbag readiness, airbag
performance, and the severity of a collision. If your
vehicle is equipped with StabiliTrak
®, steering
performance, including yaw rate, steering wheel angle,
and lateral acceleration, is also recorded. This
information has been used to improve vehicle crash
performance and may be used to improve crash
performance of future vehicles and driving safety.Unlike the data recorders on many airplanes, these
on-board systems do not record sounds, such as
conversation of vehicle occupants.
To read this information, special equipment is needed
and access to the vehicle or the device that stores
the data is required. GM will not access information
about a crash event or share it with others other than:
•with the consent of the vehicle owner or, if the
vehicle is leased, with the consent of the lessee,
•in response to an official request of police or similar
government office,
•as part of GM’s defense of litigation through the
discovery process, or
•as required by law.
In addition, once GM collects or receives data, GM may:
•use the data for GM research needs,
•make it available for research where appropriate
confidentiality is to be maintained and need is
shown, or
•share summary data which is not tied to a specific
vehicle with non-GM organizations for research
purposes.
Others, such as law enforcement, may have access to
the special equipment that can read the information
if they have access to the vehicle or the device
that stores the data.
7-10
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 call them at
1-800-333-0510 or write to:
Transport Canada
Place de Ville Tower C
330 Sparks Street
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:
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.
7-14