2004 GMC ENVOY XUV section 5

Indicator Light
The indicator light on the in¯ator switch in the rear
passenger compartment also serves as an indicator for
internal system error. If the indicator light is ¯ashing
without the load leveling function or the in¯ator being
active, turn off the ignition. The next day turn on
the ignition and check the indicator light. The vehicle
can be driven with the light ¯ashing, but if it is you
should have the vehicle serviced as soon as possible.
Adding a Snow Plow or Similar
Equipment
Your vehicle was neither designed nor intended for a
snow plow.
Notice:Adding a snow plow or similar equipment
to your vehicle can damage it, and the repairs would
not be covered by warranty. Do not install a snow
plow or similar equipment on your vehicle.
Towing a Trailer
{CAUTION:
If you do not use the correct equipment and
drive properly, you can lose control when you
pull a trailer. For example, if the trailer is too
heavy, the brakes may not work well Ð or even
at all. You and your passengers could be
seriously injured. You may also damage your
vehicle; the resulting repairs would not be
covered by your warranty. Pull a trailer only if
you have followed all the steps in this section.
Ask your dealer for advice and information
about towing a trailer with your vehicle.
Notice:Pulling a trailer improperly can damage
your vehicle and result in costly repairs that would
not be covered by your warranty. Always follow
the instructions in this section and check with your
dealer for more information about towing a trailer
with your vehicle.
To identify what the vehicle trailering capacity is for your
vehicle, you should read the information in ªWeight of
the Trailerº that appears later in this section.
4-56

Trailering is different than just driving your vehicle by
itself. Trailering means changes in acceleration, braking,
handling, durability and fuel economy. Successful,
safe trailering takes correct equipment, and it has to be
used properly.
That's the reason for this part. In it are many time-tested,
important trailering tips and safety rules. Many of
these are important for your safety and that of your
passengers. So please read this section carefully before
you pull a trailer.
If You Do Decide To Pull A Trailer
If you do, here are some important points:
·There are many different laws, including speed limit
restrictions, having to do with trailering. Make sure
your rig will be legal, not only where you live
but also where you'll be driving. A good source for
this information can be state or provincial police.
·Consider using a sway control. See ªHitchesº later
in this section.
·Don't tow a trailer at all during the ®rst 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
·Then, during the ®rst 500 miles (800 km) that you
tow a trailer, don't drive over 50 mph (80 km/h)
and don't make starts at full throttle. This helps your
engine and other parts of your vehicle wear in at
the heavier loads.
·You can tow in DRIVE (D). You may want to shift
the transmission to THIRD (3) or, if necessary, a
lower gear selection if the transmission shifts
too often (e.g., under heavy loads and/or hilly
conditions).
Three important considerations have to do with weight:
·the weight of the trailer,
·the weight of the trailer tongue
·and the weight on your vehicle's tires.
4-57

{CAUTION:
It can be dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P) with
the parking brake ®rmly set. Your vehicle
can roll.
If you have left the engine running, the vehicle
can move suddenly. You or others could be
injured. To be sure your vehicle won't move,
even when you're on fairly level ground, use
the steps that follow.
Always put the shift lever fully in PARK (P)
with the parking brake ®rmly set.
If the transfer case on four-wheel drive
vehicles is in NEUTRAL, your vehicle will be
free to roll, even if your shift lever is in
PARK (P). So, be sure the transfer case is in a
drive gear Ð not in NEUTRAL.
See ªFour-Wheel Drive (Automatic Transfer
Case)º in the Index.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
·start your engine,
·shift into a gear, and
·release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you're
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission ¯uid (don't over®ll),
engine oil, axle lubricant, belt(s), cooling system and
brake system. Each of these is covered in this manual,
and the Index will help you ®nd them quickly. If
you're trailering, it's a good idea to review these sections
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
4-65

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 Speci®cations....................................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.....................5-10
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-15
Engine Air Cleaner/Filter................................5-20
Automatic Transmission Fluid.........................5-21
Engine Coolant.............................................5-23
Radiator Pressure Cap..................................5-26
Engine Overheating.......................................5-26
Cooling System............................................5-28
Engine Fan Noise.........................................5-34
Power Steering Fluid.....................................5-35
Windshield Washer Fluid................................5-36Brakes........................................................5-37
Battery........................................................5-40
Jump Starting...............................................5-41
Rear Axle.......................................................5-46
Four-Wheel Drive............................................5-46
Front Axle......................................................5-47
Bulb Replacement..........................................5-48
Headlamps..................................................5-48
Taillamps and Turn Signal Lamps...................5-49
Replacement Bulbs.......................................5-50
Windshield Wiper Blade Replacement..............5-50
Tires..............................................................5-52
In¯ation - Tire Pressure.................................5-60
Tire Inspection and Rotation...........................5-61
When It Is Time for New Tires.......................5-63
Buying New Tires.........................................5-64
Uniform Tire Quality Grading..........................5-65
Wheel Alignment and Tire Balance..................5-66
Wheel Replacement......................................5-66
Tire Chains..................................................5-68
Accessory In¯ator.........................................5-68
If a Tire Goes Flat........................................5-70
Changing a Flat Tire.....................................5-71
Spare Tire...................................................5-83
Section 5 Service and Appearance Care
5-1

Appearance Care............................................5-83
Cleaning the Inside of Your Vehicle.................5-84
Care of Safety Belts......................................5-87
Weatherstrips...............................................5-87
Cleaning the Outside of Your Vehicle..............5-87
Sheet Metal Damage.....................................5-89
Finish Damage.............................................5-89
Underbody Maintenance................................5-90
Chemical Paint Spotting.................................5-90
Vehicle Care/Appearance Materials..................5-90
Vehicle Identi®cation......................................5-91
Vehicle Identi®cation Number (VIN).................5-91
Service Parts Identi®cation Label.....................5-92Electrical System............................................5-92
Add-On Electrical Equipment..........................5-92
Headlamps..................................................5-92
Windshield Wiper Fuses................................5-92
Power Windows and Other Power Options.......5-92
Fuses and Circuit Breakers............................5-93
Capacities and Speci®cations........................5-101
Section 5 Service and Appearance Care
5-2

When to Add Engine Oil
If the oil is at or below the L mark for the L6 engine or
the cross-hatched area at the tip of the dipstick for the V8
engine, then you will need to add at least one quart of oil.
But you must use the right kind. This section explains
what kind of oil to use. For engine oil crankcase capacity,
see
Capacities and Speci®cations on page 5-101.
Notice:Do not add too much oil. If your engine has
so much oil that the oil level gets above the F
mark that shows the proper operating range for the
L6 engine or above the cross-hatched area for
the V8 engine, your engine could be damaged.
See
Engine Compartment
Overview on page 5-12for
the location of the
engine oil ®ll cap.
Be sure to add enough oil to put the level somewhere in
the proper operating range. Push the dipstick all the
way back in when you are through.
What Kind of Engine Oil to Use
Look for two things:
·GM6094M
Your vehicle's engine requires oil meeting GM
Standard GM6094M. You should look for and use
only an oil that meets GM Standard GM6094M. L6 Engine
V8 Engine
5-16

Brakes
Brake Fluid
Your brake master cylinder reservoir is ®lled with DOT-3
brake ¯uid. SeeEngine Compartment Overview on
page 5-12for the location of the reservoir.
There are only two reasons why the brake ¯uid level in
the reservoir might go down. The ®rst is that the
brake ¯uid goes down to an acceptable level during
normal brake lining wear. When new linings are put in,
the ¯uid level goes back up. The other reason isthat ¯uid is leaking out of the brake system. If it is, you
should have your brake system ®xed, since a leak
means that sooner or later your brakes will not work
well, or will not work at all.
So, it is not a good idea to ªtop offº your brake ¯uid.
Adding brake ¯uid will not correct a leak. If you add ¯uid
when your linings are worn, then you will have too
much ¯uid when you get new brake linings. You should
add (or remove) brake ¯uid, as necessary, only when
work is done on the brake hydraulic system.
{CAUTION:
If you have too much brake ¯uid, it can spill on
the engine. The ¯uid will burn if the engine is
hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
¯uid only when work is done on the brake
hydraulic system. See ªChecking Brake Fluidº
in this section.
Refer to the Maintenance Schedule to determine when
to check your brake ¯uid. See
Scheduled Maintenance
on page 6-4.
5-37

When the differential is cold, add enough lubricant to
raise the level to 1/2 inch (12 mm) below the ®ller
plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level to the
bottom of the ®ller plug hole.
What to Use
To determine what kind of lubricant to use, seeRecommended Fluids and Lubricants on page 6-13.
Bulb Replacement
For the type of bulbs, seeReplacement Bulbs on
page 5-50.
For any bulb changing procedure not listed in this
section, contact your dealer.
Headlamps
1. Open the hood.
2. Lift the inner quick release clips.
3. Pull the headlamp assembly away from the vehicle.
4. Remove the cover from the headlamp bulb.
5. Disconnect the wiring harness (C).
6. Remove the headlamp bulb (A) or turn signal
bulb (B) by turning the socket counterclockwise.
7. To install the replacement bulb, reverse
Steps 1 through 6.
5-48