If the Light is Flashing
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed
Avoiding hard accelerations
Avoiding steep uphill grades
If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible
If the light stops ashing and remains on steady,
see “If the Light Is On Steady” following.
If the light continues to ash, when it is safe to do
so, stop the vehicle. Find a safe place to park your
vehicle. Turn the key off, wait at least 10 seconds and
restart the engine. If the light remains on steady, see
“If the Light Is On Steady” following. If the light is
still ashing, follow the previous steps, and see your
dealer for service as soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully
install the cap. SeeFilling the Tank on page 5-10.
The diagnostic system can determine if the fuel
cap has been left off or improperly installed.A loose or missing fuel cap will allow fuel to evaporate
into the atmosphere. A few driving trips with the cap
properly installed should turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-6. Poor fuel quality will
cause your engine not to run as efficiently as designed.
You may notice this as stalling after start-up, stalling
when you put the vehicle into gear, mis ring, hesitation
on acceleration, or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the
light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer can check the vehicle. Your dealer has
the proper test equipment and diagnostic tools to x
any mechanical or electrical problems that may
have developed.
3-45
Service............................................................5-4
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of
Your Vehicle..............................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-6
Gasoline Speci cations....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-7
Fuel E85 (85% Ethanol)..................................5-8
Fuels in Foreign Countries...............................5-9
Filling the Tank............................................5-10
Filling a Portable Fuel Container.....................5-12
Checking Things Under the Hood....................5-12
Hood Release..............................................5-13
Engine Compartment Overview.......................5-14
Engine Oil (Gasoline Engine)..........................5-20
Engine Oil Life System
(Gasoline Engine)......................................5-23
Engine Air Cleaner/Filter................................5-25
Automatic Transmission Fluid
(Except Allison Transmission
®) ....................5-27
Automatic Transmission Fluid
(Allison Transmission
®) ...............................5-30Manual Transmission Fluid.............................5-33
Hydraulic Clutch...........................................5-34
Engine Coolant.............................................5-35
Coolant Surge Tank Pressure Cap..................5-38
Engine Overheating.......................................5-38
Overheated Engine Protection Operating Mode
(V8 Engines Only)......................................5-40
Cooling System............................................5-40
Engine Fan Noise.........................................5-45
Power Steering Fluid.....................................5-46
Windshield Washer Fluid................................5-47
Brakes........................................................5-48
Battery........................................................5-51
Jump Starting...............................................5-52
All-Wheel Drive..............................................5-57
Rear Axle.......................................................5-58
Four-Wheel Drive............................................5-59
Front Axle......................................................5-60
Noise Control System.....................................5-61
Tampering with Noise Control System
Prohibited.................................................5-61
Section 5 Service and Appearance Care
5-1
Gasoline Octane
For all except vehicles with the 6.0L V8 (VIN Code N)
engine, use regular unleaded gasoline with a posted
octane of 87 or higher. If the octane is less than 87, you
may get a heavy knocking noise when you drive. If this
occurs, use a gasoline rated at 87 octane or higher as
soon as possible. Otherwise, you might damage your
engine. A little pinging noise when you accelerate or drive
uphill is considered normal. This does not indicate a
problem exists or that a higher-octane fuel is necessary.
If you are using 87 octane or higher-octane fuel and hear
heavy knocking, your engine needs service.
If you have the 6.0L V8 (VIN Code N) engine, use
premium unleaded gasoline with a posted octane of
91 or higher for best performance. You may also use
middle grade or regular unleaded gasoline rated at
87 octane or higher, but your vehicle’s acceleration may
be slightly reduced. If the octane is less than 87, you may
get a heavy knocking noise when you drive. If this occurs,
use gasoline rated at 87 octane or higher as soon as
possible. Otherwise, you might damage your engine.
Gasoline Speci cations
It is recommended that gasoline meet speci cations
which were developed by automobile manufacturers
around the world and contained in the World-Wide Fuel
Charter which is available from the Alliance of Automobile
Manufacturers at www.autoalliance.org/fuel_charter.htm.
Gasoline meeting these speci cations could provide
improved driveability and emission control system
performance compared to other gasoline.
California Fuel
If your vehicle is certi ed to meet California Emissions
Standards, it is designed to operate on fuels that meet
California speci cations. See the underhood emission
control label. If this fuel is not available in states adopting
California emissions standards, your vehicle will operate
satisfactorily on fuels meeting federal speci cations, but
emission control system performance may be affected.
The malfunction indicator lamp may turn on and your
vehicle may fail a smog-check test. SeeMalfunction
Indicator Lamp on page 3-44. If this occurs, return to your
authorized GM dealer for diagnosis. If it is determined
that the condition is caused by the type of fuel used,
repairs may not be covered by your warranty.
5-6
Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work properly. In
most cases, you should not have to add anything to your
fuel. However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. General Motors
recommends that you buy gasolines that are advertised
to help keep fuel injectors and intake valves clean. If your
vehicle experiences problems due to dirty injectors or
valves, try a different brand of gasoline. Also, your
GM dealer has additives that will help correct and prevent
most deposit-related problems.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area to contribute to clean air. General Motors
recommends that you use these gasolines, particularly if
they comply with the speci cations described earlier.Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.
Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does
not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system may
be affected. The malfunction indicator lamp may turn on.
If this occurs, return to your authorized GM dealer
for service.
5-7
Using the Maintenance Schedule
We at General Motors want to help you keep your vehicle
in good working condition. But we do not know exactly
how you will drive it. You may drive very short distances
only a few times a week. Or you may drive long distances
all the time in very hot, dusty weather. You may use your
vehicle in making deliveries. Or you may drive it to work,
to do errands or in many other ways.
Because of all the different ways people use their
vehicles, maintenance needs vary. You may need more
frequent checks and replacements. So please read
the following and note how you drive. If you have any
questions on how to keep your vehicle in good condition,
see your GM Goodwrench
®dealer.
This schedule is for vehicles that:
carry passengers and cargo within recommended
limits. You will nd these limits on the tire and
loading information label. SeeLoading Your Vehicle
on page 4-50.
are driven on reasonable road surfaces within legal
driving limits.
are driven off-road in the recommended manner.
SeeOff-Road Driving on page 4-20.
use the recommended fuel. SeeGasoline Octane
on page 5-6.The services inScheduled Maintenance (Gasoline
Engine) on page 6-4should be performed when
indicated. SeeAdditional Required Services (Gasoline
Engine) on page 6-7andMaintenance Footnotes
(Gasoline Engine) on page 6-9for further information.
{CAUTION:
Performing maintenance work on a vehicle can
be dangerous. In trying to do some jobs, you
can be seriously injured. Do your own
maintenance work only if you have the
required know-how and the proper tools and
equipment for the job. If you have any doubt,
see your GM Goodwrench
®dealer to have a
quali ed technician do the work.
Some maintenance services can be complex. So,
unless you are technically quali ed and have the
necessary equipment, you should have your GM
Goodwrench
®dealer do these jobs.
6-3
Front Reading Lamps......................................3-18
Front Storage Area.........................................2-75
Fuel............................................................... 5-5
Additives...................................................... 5-7
California Fuel.............................................. 5-6
E85 (85% Ethanol)........................................ 5-8
Filling a Portable Fuel Container....................5-12
Filling Your Tank..........................................5-10
Fuels in Foreign Countries.............................. 5-9
Gage .........................................................3-49
Gasoline Octane........................................... 5-6
Gasoline Speci cations.................................. 5-6
Low Warning Light.......................................3-49
Fuses
Center Instrument Panel Fuse Block.............5-126
Fuses and Circuit Breakers.........................5-123
Instrument Panel Fuse Block.......................5-124
Underhood Fuse Block...............................5-127
Windshield Wiper.......................................5-123
GGage
Engine Coolant Temperature.........................3-42
Fuel..........................................................3-49
Oil Pressure...............................................3-46
Speedometer..............................................3-33
Tachometer.................................................3-33
Transmission Temperature.............................3-42
Voltmeter Gage...........................................3-39Garage Door Opener.......................................2-70
Gasoline
Octane........................................................ 5-6
Speci cations............................................... 5-6
Glove Box.....................................................2-75
GM Mobility Reimbursement Program.................. 7-5
H
Hazard Warning Flashers................................... 3-6
Head Restraints............................................... 1-7
Headlamps............................................3-13, 5-63
Automatic Headlamp System.........................3-15
Bulb Replacement.......................................5-62
Daytime Running Lamps...............................3-14
Flash-to-Pass............................................... 3-9
Front Turn Signal, Sidemarker and Daytime
Running Lamps........................................5-64
Halogen Bulbs............................................5-62
High/Low Beam Changer................................ 3-8
On Reminder..............................................3-14
Pickup Box Identi cation and Fender
Marker Lamps.........................................5-69
Roof Marker Lamps.....................................5-66
Heated Seats................................................... 1-5
Heater...................................................3-20, 3-22
Heater...........................................................3-24
Highbeam On Light.........................................3-48
Highway Hypnosis...........................................4-41
6