air condition GMC ENVOY 2002 User Guide

5-17
Engine Fan Noise
This vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions the clutch is not engaged. This improves
fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing, and/or high outside
temperatures, the fan speed increases when the clutch
engages. So you may hear an increase in fan noise.
This is normal and should not be mistaken as the
transmission slipping or making extra shifts. It is merely
the cooling system functioning properly. The fan will
slow down when additional cooling is not required and
the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
If a Tire Goes Flat
It's unusual for a tire to ªblow outº while you're driving,
especially if you maintain your tires properly. If air goes
out of a tire, it's much more likely to leak out slowly.
But if you should ever have a ªblowout,º here are a few
tips about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you'd use in a
skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop
-- well off the road if possible.
If a tire goes flat, the next part shows how to use your
jacking equipment to change a flat tire safely.

6-4 Gasoline Specifications
It is recommended that gasoline meet specifications
which were developed by the American Automobile
Manufacturers Association and endorsed by the
Canadian Vehicle Manufacturers' Association for better
vehicle performance and engine protection. Gasolines
meeting these specifications could provide improved
driveability and emission control system performance
compared to other gasolines.
In Canada, look for
the ªAuto Makers'
Choiceº label on
the pump.
Canada Only
California Fuel
If your vehicle is certified to meet California Emission
Standards (see the underhood emission control label),
it is designed to operate on fuels that meet California
specifications. If this fuel is not available in states
adopting California emissions standards, your vehicle
will operate satisfactorily on fuels meeting federal
specifications, but emission control system performance
may be affected. The malfunction indicator lamp may
turn on (see ªMalfunction Indicator Lampº in the Index)
and your vehicle may fail a smog
-check test. 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.

6-31
NOTICE:

Using the wrong fluid can badly damage
brake system parts. For example, just a few
drops of mineral
-based oil, such as engine
oil, in your brake system can damage brake
system parts so badly that they'll have to be
replaced. Don't let someone put in the
wrong kind of fluid.

If you spill brake fluid on your vehicle's
painted surfaces, the paint finish can be
damaged. Be careful not to spill brake fluid
on your vehicle. If you do, wash it off
immediately. See ªAppearance Careº in
the Index.
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 firmly).
CAUTION:
The brake wear warning sound means that soon
your brakes won't 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 first applied or lightly
applied. This does not mean something is wrong with
your brakes.

6-44
Temperature -- A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire's resistance to the generation of
heat and its ability to dissipate heat when tested under
controlled conditions on a specified indoor laboratory
test wheel. Sustained high temperature can cause the
material of the tire to degenerate and reduce tire life, and
excessive temperature can lead to sudden tire failure.
The grade C corresponds to a level of performance
which all passenger car tires must meet under the
Federal Motor Vehicle Safety Standard No. 109.
Grades B and A represent higher levels of performance
on the laboratory test wheel than the minimum required
by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inflated and not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at the factory to give you the longest tire life
and best overall performance.
Scheduled wheel alignment and wheel balancing are not
needed. However, if you notice unusual tire wear or
your vehicle pulling one way or the other, the alignment
may need to be reset. If you notice your vehicle
vibrating when driving on a smooth road, your wheels
may need to be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded. If wheel nuts keep coming loose, the wheel,
wheel bolts and wheel nuts should be replaced. If the
wheel leaks air, replace it (except some aluminum
wheels, which can sometimes be repaired). See your
dealer if any of these conditions exist.
Your dealer will know the kind of wheel you need.

6-53
Finish Damage
Any stone chips, fractures or deep scratches in the finish
should be repaired right away. Bare metal will corrode
quickly and may develop into a major repair expense.
Minor chips and scratches can be repaired with touch
-up
materials available from your dealer or other service
outlets. Larger areas of finish damage can be corrected
in your dealer's body and paint shop.
Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect on the underbody. If these are not
removed, accelerated corrosion (rust) can occur on the
underbody parts such as fuel lines, frame, floor pan
and exhaust system even though they have
corrosion protection.
At least every spring, flush these materials from the
underbody with plain water. Clean any areas where mud
and other debris can collect. Dirt packed in closed areas
of the frame should be loosened before being flushed.
Your dealer or an underbody car washing system can do
this for you.
Chemical Paint Spotting
Some weather and atmospheric conditions can create
a chemical fallout. Airborne pollutants can fall upon
and attack painted surfaces on your vehicle. This
damage can take two forms: blotchy, ringlet
-shaped
discolorations, and small irregular dark spots etched
into the paint surface.
Although no defect in the paint job causes this, GMC
will repair, at no charge to the owner, the surfaces of
new vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occurs first.

6-57 Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from
short circuits by a combination of fuses and circuit
breakers. This greatly reduces the chance of fires caused
by electrical problems.
Look at the silver
-colored band inside the fuse. If the
band is broken or melted, replace the fuse. Be sure you
replace a bad fuse with a new one of the identical size
and rating.
If you ever have a problem on the road and don't have
a spare fuse, you can borrow one that has the same
amperage. Just pick some feature of your vehicle that
you can get along without
-- like the radio or cigarette
lighter
-- and use its fuse, if it is the correct amperage.
Replace it as soon as you can.
Air Conditioning Refrigerant Capacity
If you do your own service work, you'll need the proper
service manual. See ªDoing Your Own Service Workº in
the Index for additional information. It is recommended
that service work on your air conditioning system be
performed by a qualified technician.Engine Compartment Fuse Block
The fuse block is located under the hood in the engine
compartment on the driver's side of the vehicle. See
ªEngine Compartment Overviewº in the Index for more
information on location.
Remove the cover by turning the fastener
counterclockwise. To reinstall the fuse panel cover, push
in and turn the fastener clockwise.

6-60
Mini Fuses Usage
30 Air Conditioning
31 TBC
50 Passenger's Side Trailer TRN
51 Driver's Side Trailer TRN
52 Hazard Flashers
J
-Case Fuses Usage
32 Trailer
33 Anti
-Lock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Ignition B
Micro Relays Usage
37 Headlamp Washer
38 Rear Window Washer
39 Fog LampsMicro Relays Usage
40 Horn
41 Fuel Pump
42 Windshield Wipers/Washer
43 High
-Beam Headlamp
44 Air Conditioning
Solid State
RelaysUsage
45 Cooling Fan
46 HDM
Mini Relay Usage
47 Starter
Miscellaneous Usage
48 Instrument Panel Battery
49 Fuse Puller

6-64 Wheel and Tires
Wheel Nut Torque 100 lb-ft (140 N´m) . . . . . . . . . . .
Capacities
Cooling System 13.9 quarts (13.1 L). . . . . . . . . . . . .
Air Conditioning R
-134a 1.9 lbs. (0.9 kg). . . . . . . . . .
Use Refrigerant Oil, R
-134a Systems
Engine Oil with Filter 7.0 quarts (6.6 L). . . . . . . . . .
Transmission
(Drain and Refill) 5.0 quarts (4.7 L). . . . . . . . . . . .
Differential Fluid
Rear 4.0 pints (1.9 L). . . . . . . . . . . . . . . . . . . . . . . .
Front 2.6 pints (0.8 L). . . . . . . . . . . . . . . . . . . . . . .
Fuel Tank 18.7 U.S. gallons (70.8 L). . . . . . . . . . . . .
All capacities are approximate. When adding, be sure to
fill to the appropriate level, as recommended in this
manual. Recheck the fluid level after filling.
Normal Maintenance
Replacement Parts
Engine Oil Filter PF58*. . . . . . . . . . . . . . . . . . . . . . .
Engine Air Cleaner/Filter A2014C*. . . . . . . . . . . . . . .
Automatic Transmission
Filter Kit GM Part No. 24200796. . . . . . . . . . . . . . .
Spark Plugs 41
-965* . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Filter GF831*. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Windshield Wiper Blade 20.0 inches (50.8 cm). . . . .
Backglass Wiper Blade 14.0 inches (35.6 cm). . . . . .
*ACDelco

part number

7-2
Have you purchased the GM Protection Plan? The Plan
supplements your new vehicle warranties. See your
Warranty and Owner Assistance booklet or your dealer
for details.
Introduction
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle in good working condition, but also helps the
environment. All recommended maintenance procedures
are important. Improper vehicle maintenance can even
affect the quality of the air we breathe. Improper fluid
levels or the wrong tire inflation can increase the level
of emissions from your vehicle. To help protect our
environment, and to keep your vehicle in good
condition, please maintain your vehicle properly.
Maintenance Requirements
Maintenance intervals, checks, inspections and
recommended fluids and lubricants as prescribed in this
manual are necessary to keep your vehicle in good
working condition. Any damage caused by failure to
follow recommended maintenance may not be covered
by warranty.

7-3 How This Section is Organized
This maintenance schedule is divided into five parts:
ªPart A: Scheduled Maintenance Servicesº explains
what to have done and how often. Some of these
services can be complex, so unless you are technically
qualified and have the necessary equipment, you should
let your dealer's service department or another qualified
service center do these jobs.
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, have a qualified
technician do the work.
If you want to get the service information, see ªService
and Owner Publicationsº in the Index.ªPart B: Owner Checks and Servicesº tells you
what should be checked and when. It also explains
what you can easily do to help keep your vehicle in
good condition.
ªPart C: Periodic Maintenance Inspectionsº explains
important inspections that your dealer's service
department or another qualified service center
should perform.
ªPart D: Recommended Fluids and Lubricantsº lists
some recommended products necessary to help keep
your vehicle properly maintained. These products, or
their equivalents, should be used whether you do the
work yourself or have it done.
ªPart E: Maintenance Recordº is a place for
you to record and keep track of the maintenance
performed on your vehicle. Keep your maintenance
receipts. They may be needed to qualify your vehicle
for warranty repairs.