2004 GMC ENVOY XL wheel

Dolly Towing
Two-Wheel-Drive Vehicles
Two-wheel-drive vehicles should not be dolly towed.
Two-wheel-drive transmissions have no provisions
for internal lubrication while being towed. To properly
tow these vehicles, they should be placed on a platform
trailer with all four wheels off the ground.
Four-Wheel-Drive Vehicles
Four-wheel-drive vehicles can be dolly towed with
the rear wheels on the ground.
Use the following procedure to tow your vehicle:
1. Drive the vehicle onto the tow dolly.
2. Shift the automatic transmission to PARK (P).
3. Turn the engine off, but leave the ignition on.
4. Firmly set the parking brake.
5. Securely attach the vehicle being towed
to the dolly.
{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer
case into NEUTRAL can cause your vehicle
to roll even if the transmission is in Park (P).
You or others could be injured. Make sure
the parking brake is rmly set before you shift
the transfer case to NEUTRAL.
6. Shift the transfer case to NEUTRAL. See
Four-Wheel Drive on page 2-26for the proper
procedure to select the NEUTRAL position for
your vehicle.
7. Release the parking brake only after the vehicle
being towed is rmly attached to the towing
vehicle.
8. Turn the ignition off and lock the steering column.
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Before you start, check all trailer hitch parts and and
attachments, safety chains, electrical connection, lamps,
tires and mirror adjustment. If the trailer has electric
brakes, start your vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer
brakes are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as
you would when driving your vehicle without a trailer.
This can help you avoid situations that require
heavy braking and sudden turns.
Passing
You’ll need more passing distance up ahead when
you’re towing a trailer. And, because you’re a good
deal longer, you’ll need to go much farther beyond the
passed vehicle before you can return to your lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer to the left, just move that hand
to the left. To move the trailer to the right, move your
hand to the right. Always back up slowly and, if possible,
have someone guide you.
Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns than
normal. Do this so your trailer won’t strike soft shoulders,
curbs, road signs, trees or other objects. Avoid jerky or
sudden maneuvers. Signal well in advance.
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Parking on Hills
{CAUTION:
You really should not park your vehicle, with
a trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet. When parking uphill, turn your wheels
away from the curb. When parking downhill, turn
your wheels into the curb.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake, and then shift into PARK (P).
5. Release the regular brakes.
{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 — not
in NEUTRAL.
See “Four-Wheel Drive (Automatic Transfer
Case)” in the Index.
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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

Brake Wear
Your vehicle has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that make a
high-pitched warning sound when the brake pads are
worn and new pads are needed. The sound may come
and go or be heard all the time your vehicle is moving
(except when you are pushing on the brake pedal rmly).
{CAUTION:
The brake wear warning sound means that soon
your brakes will not work well. That could lead
to an accident. When you hear the brake wear
warning sound, have your vehicle serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes are rst applied or lightly
applied. This does not mean something is wrong with
your brakes.Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to GM torque specications.
Brake linings should always be replaced as complete
axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not return
to normal height, or if there is a rapid increase in pedal
travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
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Jump Starting
If your battery has run down, you may want to use
another vehicle and some jumper cables to start your
vehicle. But please use the following steps to do it safely.
{CAUTION:
Batteries can hurt you. They can be dangerous
because:
They contain acid that can burn you.
They contain gas that can explode or ignite.
They contain enough electricity to
burn you.
If you do not follow these steps exactly, some
or all of these things can hurt you.
Notice:Ignoring these steps could result in costly
damage to your vehicle that would not be covered
by your warranty.Trying to start your vehicle by pushing or pulling it
will not work, and it could damage your vehicle.
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
Notice:If the other vehicle’s system is not a 12-volt
system with a negative ground, both vehicles can
be damaged. Only use vehicles with 12-volt systems
with negative grounds to jump start your vehicle.
2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren’t touching
each other. If they are, it could cause a ground
connection you don’t want. You wouldn’t be able to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling, set the
parking brake rmly on both vehicles involved in the
jump start procedure. Put an automatic transmission
in PARK (P) or a manual transmission in NEUTRAL
before setting the parking brake. If you have a
four-wheel-drive vehicle, be sure the transfer case
is not in NEUTRAL.
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Four-Wheel Drive
Transfer Case
When to Check Lubricant
It is not necessary to regularly check uid unless you
suspect there is a leak or you hear an unusual noise.
A uid loss could indicate a problem. Have it inspected
and repaired.
How to Check Lubricant
To get an accurate
reading, the vehicle
should be on a level
surface.If the level is below the bottom of the ller plug hole,
you’ll need to add some lubricant. Add enough lubricant
to raise the level to the bottom of the ller plug hole.
Use care not to overtighten the plug.
What to Use
To determine what kind of lubricant to use, see
Recommended Fluids and Lubricants on page 6-13.
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(C) Aspect Ratio:A two-digit number that indicates
the tire height-to-width measurements. For example,
if the tire size aspect ratio is “75,” as shown in item “C”
of the illustration, it would mean that the tire’s sidewall
is 75% as high as it is wide.
(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire. The letter
“R” means radial ply construction; the letter “D” means
diagonal or bias ply construction; and the letter “B”
means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:The service description
indicates the load range and speed rating of a tire.
The load index can range from 1 to 279. Speed ratings
range from “A” to “Z”.(A) Light Truck (LT-Metric) Tire:The United States
version of a metric tire sizing system. The letter “LT”
as the rst two characters in the tire size means a light
truck tire engineered to standards set by the U. S.
Tire and Rim Association.
(B) Tire Width:The three-digit number indicates the
tire section width in millimeters from sidewall to sidewall.
(C) Aspect Ratio:A two-digit number that indicates
the tire height-to-width measurements. For example,
if the tire size aspect ratio is “75,” as shown in item “C”
of the illustration, it would mean that the tire’s sidewall
is 75% as high as it is wide.Light Truck (LT-Metric) Tire
5-60