tires GMC ENVOY 2002 Owner's Guide

6-41
After the tires have been rotated, adjust the front and
rear inflation pressures as shown on the
Certification/Tire label. Make certain that all wheel nuts
are properly tightened. See ªWheel Nut Torqueº in
the Index.
CAUTION:
Rust or dirt on a wheel, or on the parts to which
it is fastened, can make wheel nuts become loose
after a time. The wheel could come off and cause
an accident. When you change a wheel, remove
any rust or dirt from places where the wheel
attaches to the vehicle. In an emergency, you can
use a cloth or a paper towel to do this; but be
sure to use a scraper or wire brush later, if you
need to, to get all the rust or dirt off. See
ªChanging a Flat Tireº in the Index.
When It's Time for New Tires
One way to tell when it's
time for new tires is to
check the treadwear
indicators, which will
appear when your tires have
only 1/16 inch (1.6 mm) or
less of tread remaining.
You need a new tire if any of the following statements
are true:

You can see the indicators at three or more places
around the tire.

You can see cord or fabric showing through the
tire's rubber.

The tread or sidewall is cracked, cut or snagged deep
enough to show cord or fabric.

The tire has a bump, bulge or split.

The tire has a puncture, cut or other damage that
can't be repaired well because of the size or location
of the damage.

6-42 Buying New Tires
To find out what kind and size of tires you need, look at
the Certification/Tire label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number on each tire's sidewall. When you get new tires,
get ones with that same TPC Spec number. That way
your vehicle will continue to have tires that are designed
to give proper endurance, handling, speed rating,
traction, ride and other things during normal service on
your vehicle. If your tires have an all
-season tread
design, the TPC number will be followed by an ªMSº
(for mud and snow).
If you ever replace your tires with those not having
a TPC Spec number, make sure they are the same
size, load range, speed rating and construction type
(bias, bias
-belted or radial) as your original tires.
CAUTION:
Mixing tires could cause you to lose control while
driving. If you mix tires of different sizes or types
(radial and bias
-belted tires), the vehicle may not
handle properly, and you could have a crash.
Using tires of different sizes may also cause
damage to your vehicle. Be sure to use the same
size and type tires on all wheels.
CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim flanges could develop cracks after
many miles of driving. A tire and/or wheel could
fail suddenly, causing a crash. Use only radial
-ply
tires with the wheels on your vehicle.

6-43 Uniform Tire Quality Grading
Quality grades can be found where applicable on the tire
sidewall between tread shoulder and maximum section
width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, which grades tires by
treadwear, traction and temperature performance.
(This applies only to vehicles sold in the United States.)
The grades are molded on the sidewalls of most
passenger car tires. The Uniform Tire Quality Grading
system does not apply to deep tread, winter
-type snow
tires, space
-saver or temporary use spare tires, tires with
nominal rim diameters of 10 to 12 inches (25 to 30 cm),
or to some limited
-production tires.
While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course.
For example, a tire graded 150 would wear one and
a half (1 1/2) times as well on the government course
as a tire graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart significantly from the norm
due to variations in driving habits, service practices and
differences in road characteristics and climate.
Traction
-- AA, A, B, C
The traction grades, from highest to lowest, are AA,
A, B, and C. Those grades represent the tire's ability
to stop on wet pavement as measured under controlled
conditions on specified government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance. Warning: The traction grade
assigned to this tire is based on straight
-ahead braking
traction tests, and does not include acceleration,
cornering, hydroplaning, or peak traction characteristics.

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.

6-45
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted the
same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts and wheel nuts for your vehicle.
CAUTION:
Using the wrong replacement wheels, wheel bolts
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make
you lose control. You could have a collision in
which you or others could be injured. Always
use the correct wheel, wheel bolts and wheel nuts
for replacement.
NOTICE:
The wrong wheel can also cause problems with
bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper
height, vehicle ground clearance and tire or tire
chain clearance to the body and chassis.
See ªChanging a Flat Tireº in the Index for
more information.
Used Replacement Wheels
CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can't know how it's been used or
how far it's been driven. It could fail suddenly
and cause a crash. If you have to replace a wheel,
use a new GM original equipment wheel.

6-52
Cleaning Aluminum Wheels
Keep your wheels clean using a soft clean cloth
with mild soap and water. Rinse with clean water.
After rinsing thoroughly, dry with a soft clean towel.
A wax may then be applied.
The surface of these wheels is similar to the painted
surface of your vehicle. Don't use strong soaps,
chemicals, abrasive polishes, abrasive cleaners, cleaners
with acid or abrasive cleaning brushes on them because
you could damage the surface. Do not use chrome polish
on aluminum wheels.
Don't take your vehicle through an automatic car
wash that has silicon carbide tire cleaning brushes.
These brushes can also damage the surface of
these wheels.
Cleaning Tires
To clean your tires, use a stiff brush with a tire cleaner.
NOTICE:
When applying a tire dressing always take care to
wipe off any overspray or splash from all painted
surfaces on the body or wheels of the vehicle.
Petroleum
-based products may damage the paint
finish and tires.
Sheet Metal Damage
If your vehicle is damaged and requires sheet metal
repair or replacement, make sure the body repair shop
applies anti
-corrosion material to the parts repaired or
replaced to restore corrosion protection.
Original manufacturer replacement parts will provide
the corrosion protection while maintaining the warranty.

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

Scheduled Maintenance
7-9
7,500 Miles (12 500 km)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.

Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
15,000 Miles (25 000 km)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.

Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
22,500 Miles (37 500 km)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.

Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE

Scheduled Maintenance
7-10
30,000 Miles (50 000 km)

Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.

Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)

Replace fuel filter.
An Emission Control Service. (See footnote
.)
37,500 Miles (62 500 km)
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.
Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
45,000 Miles (75 000 km)
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.
Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE

Scheduled Maintenance
7-11
50,000 Miles (83 000 km)

Change automatic transmission fluid and filter if the vehicle is mainly driven
under one or more of these conditions:
± In heavy city traffic where the outside temperature regularly reaches 90
F
(32
C) or higher.
± In hilly or mountainous terrain.
± When doing frequent trailer towing.
± Uses such as found in taxi, police or delivery service.
If you do not use your vehicle under any of these conditions, change the fluid
and filter at 100,000 miles (166 000 km).
Automatic Transfer Case Only: Change transfer case fluid.
52,500 Miles (87 500 km)
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.
Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE