2004 GMC ENVOY XL octane

Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-4. 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, misring, 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.Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the SERVICE
ENGINE SOON or CHECK ENGINE light is on or not
working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen if
you have recently replaced your battery or if your battery
has run down. The diagnostic system is designed to
evaluate critical emission control systems during normal
driving. This may take several days of routine driving.
If you have done this and your vehicle still does not pass
the inspection for lack of OBD system readiness, your
GM dealer can prepare the vehicle for inspection.
3-45

Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside
of Your Vehicle...........................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Specications....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-7
Filling a Portable Fuel Container.......................5-9
Checking Things Under the Hood....................5-10
Hood Release..............................................5-10
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-16
Engine Air Cleaner/Filter................................5-21
Automatic Transmission Fluid.........................5-22
Engine Coolant.............................................5-24
Radiator Pressure Cap..................................5-27
Engine Overheating.......................................5-28
Cooling System............................................5-30
Engine Fan Noise.........................................5-36
Power Steering Fluid.....................................5-37Windshield Washer Fluid................................5-38
Brakes........................................................5-39
Battery........................................................5-42
Jump Starting...............................................5-43
Rear Axle.......................................................5-48
Four-Wheel Drive............................................5-49
Front Axle......................................................5-50
Bulb Replacement..........................................5-51
Halogen Bulbs..............................................5-51
Headlamps..................................................5-51
Front Turn Signal and Sidemarker Lamps........5-51
Taillamps and Turn Signal Lamps...................5-52
Replacement Bulbs.......................................5-53
Windshield Wiper Blade Replacement..............5-53
Tires..............................................................5-55
Ination - Tire Pressure.................................5-64
Tire Inspection and Rotation...........................5-65
When It Is Time for New Tires.......................5-66
Buying New Tires.........................................5-67
Uniform Tire Quality Grading..........................5-68
Wheel Alignment and Tire Balance..................5-69
Wheel Replacement......................................5-69
Tire Chains..................................................5-71
Section 5 Service and Appearance Care
5-1

You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. SeeMaintenance Record on page 6-16.
{CAUTION:
You can be injured and your vehicle could be
damaged if you try to do service work on a
vehicle without knowing enough about it.
Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.
Be sure to use the proper nuts, bolts and
other fasteners. “English” and “metric”
fasteners can be easily confused. If you
use the wrong fasteners, parts can later
break or fall off. You could be hurt.
Adding Equipment to the Outside
of Your Vehicle
Things you might add to the outside of your vehicle
can affect the airow around it. This may cause
wind noise and affect windshield washer performance.
Check with your dealer before adding equipment to
the outside of your vehicle.
Fuel
Use of the recommended fuel is an important part of the
proper maintenance of your vehicle.
Gasoline Octane
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.
5-4

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.
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.
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 specications 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.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may be hard
to nd. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not
be covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
5-6

Using Your 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 4-49.
are driven on reasonable road surfaces within legal
driving limits.
are driven off-road in the recommended manner.
SeeOff-Road Driving with Your Four-Wheel-Drive
Vehicle on page 4-16.
use the recommended fuel. SeeGasoline Octane
on page 5-4.The services inScheduled Maintenance on page 6-4
should be performed when indicated. SeeAdditional
Required Services on page 6-6andMaintenance
Footnotes on page 6-8for 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
qualied technician do the work.
Some maintenance services can be complex. So, unless
you are technically qualied and have the necessary
equipment, you should have your GM Goodwrench
dealer do these jobs.
When you go to your GM Goodwrench dealer for your
service needs, you will know that GM-trained and
supported service technicians will perform the work
using genuine GM parts.
6-3

Erasing HomeLink®Buttons..............................2-45
Event Data Recorders (EDR)............................7-10
Exit Lighting...................................................3-19
Express Down Window....................................2-16
Extender, Safety Belt.......................................1-26
Exterior Lamps...............................................3-16
F
Filter
Engine Air Cleaner......................................5-21
Finding a Program Type (PTY)
Station (RDS and XM™)..............3-69, 3-80, 3-95
Finding a Station............................3-67, 3-78, 3-93
Finish Care....................................................5-92
Finish Damage...............................................5-93
Fixed Mast Antenna.......................................3-122
Flash-to-Pass................................................... 3-9
Flat Tire........................................................5-73
Flat Tire, Changing.........................................5-74
Fluid
Automatic Transmission................................5-22
Power Steering...........................................5-37
Windshield Washer......................................5-38
FM Stereo....................................................3-120
Fog Lamps....................................................3-18
Following Distance..........................................4-62
Four-Wheel Drive....................................2-26, 5-49
Front Axle......................................................5-50Front Storage Area.........................................2-47
Fuel............................................................... 5-4
Additives...................................................... 5-6
California Fuel.............................................. 5-5
Filling a Portable Fuel Container..................... 5-9
Filling Your Tank........................................... 5-7
Fuels in Foreign Countries.............................. 5-6
Gage.........................................................3-50
Gasoline Octane........................................... 5-4
Gasoline Specications.................................. 5-5
Low Warning Light.......................................3-50
Fuel Information..............................................3-52
FUEL LEVEL LOW.........................................3-62
Fuses
Fuses and Circuit Breakers...........................5-97
Windshield Wiper.........................................5-96
G
Gage
Check Gages Warning Light..........................3-49
Engine Coolant Temperature.........................3-42
Fuel..........................................................3-50
Oil Pressure...............................................3-46
Speedometer..............................................3-37
Tachometer.................................................3-37
Voltmeter Gage...........................................3-40
Garage Door Opener.......................................2-42
6

Gasoline
Octane........................................................ 5-4
Specications............................................... 5-5
Gate Ajar Light...............................................3-49
Gate Operator and Canadian Programming........2-45
Getting Familiar with Off-Road Driving................4-19
Glove Box.....................................................2-46
GM Mobility Program for Persons
with Disabilities............................................. 7-6
H
Hazard Warning Flashers................................... 3-6
Head Restraints............................................... 1-5
Headlamp High/Low-Beam Changer.................... 3-9
Headlamp Washer..........................................3-12
Headlamps....................................................5-51
Bulb Replacement.......................................5-51
Electrical System.........................................5-96
Front Turn Signal and Sidemarker Lamps.......5-51
Halogen Bulbs............................................5-51
Headphones.................................................3-107
Heated Seats................................................... 1-3
Highway Hypnosis...........................................4-37
Hill and Mountain Roads..................................4-38
Hitches..........................................................4-59
HomeLink
®Transmitter....................................2-42HomeLink
®Transmitter, Programming................2-43
Hood
Checking Things Under................................5-10
Release.....................................................5-10
Horn............................................................... 3-7
How to Add Coolant to the Coolant
Recovery Tank............................................5-32
How to Add Coolant to the Radiator..................5-34
How to Add Fluid............................................5-24
How to Check Lubricant...................................5-48
How to Check Power Steering Fluid..................5-37
How to Use This Manual...................................... ii
How to Wear Safety Belts Properly...................1-14
Hydroplaning..................................................4-32
I
ICE POSSIBLE..............................................3-62
If No Steam Is Coming From Your Engine..........5-29
If Steam Is Coming From Your Engine...............5-28
If the Light Is Flashing.....................................3-44
If the Light Is On Steady.................................3-44
If You Are Caught in a Blizzard.........................4-42
If You Are Stuck in Sand, Mud, Ice or Snow.......4-44
If You Do Decide To Pull A Trailer.....................4-56
Ignition Positions.............................................2-20
Infants and Young Children, Restraints...............1-29
7