2003 GMC ENVOY traction control

Buying New Tires
To ®nd out what kind and size of tires you need, look at
the Certi®cation/Tire label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Speci®cation (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 ¯anges 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.
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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 speci®ed government test course.
For example, a tire graded 150 would wear one and
a half (1.5) 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 signi®cantly 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 speci®ed 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.
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Tire Chains
{CAUTION:
Don't use tire chains. There's not enough
clearance. Tire chains used on a vehicle without
the proper amount of clearance can cause
damage to the brakes, suspension or other
vehicle parts. The area damaged by the tire
chains could cause you to lose control of your
vehicle and you or others may be injured in a
crash. Use another type of traction device only
if its manufacturer recommends it for use on
your vehicle and tire size combination and road
conditions. Follow that manufacturer's
instructions. To help avoid damage to your
vehicle, drive slowly, readjust or remove the
device if it's contacting your vehicle, and don't
spin your wheels. If you do ®nd traction devices
that will ®t, install them on the rear tires.
Accessory In¯ator
Your vehicle may be equipped with an air in¯ator
system. You can in¯ate things like basketballs and
bicycle tires. Also, you can use it to bring your tire
pressure up to the proper pressure. It is not designed to
in¯ate large objects which will require more than ®ve
minutes to in¯ate, such as an air mattress.
The air in¯ator is often
located in the rear
compartment on the
passenger's side of the
vehicle behind an
access cover.
To remove the cover, pull the two tabs on the cover and
pull it off.
5-62

Top Strap Anchor Location...............................1-41
Top Strap......................................................1-40
Torque Lock...................................................2-31
Total Weight on Your Vehicle's Tires..................4-54
Towing..........................................................4-45
Recreational Vehicle.....................................4-45
Towing a Trailer..........................................4-50
Your Vehicle...............................................4-45
Traction........................................................... 4-8
Assist System (TAS)...................................... 4-8
Trailer Brakes.................................................4-55
Trailer Wiring Harness.....................................4-60
TRANS HOT IDLE ENGINE.............................3-61
Transfer Case and Front Axle
(Four-Wheel Drive) Inspection.......................6-17
Transfer Case................................................5-48
Transmission Operation, Automatic....................2-23
Transmission, Transaxle, Transfer Case Unit
Repair Manual............................................7-10
Transmission..................................................5-21
Fluid, Automatic...........................................5-21
Transportation Options...................................... 7-7
Travel Note Recorder......................................2-45
Traveling to Remote Areas...............................4-17
Trip Information..............................................3-51
Trip Odometer................................................3-36
Turn and Lane Change Signals.......................... 3-8
TURN SIGNAL ON.........................................3-61
Turn Signal/Multifunction Lever........................... 3-7Turn Signals When Towing a Trailer..................4-57
Two-Wheel-Drive Vehicles................................4-46
U
Underbody Flushing Service.............................6-15
Understanding Radio Reception.......................3-105
Uniform Tire Quality Grading............................5-59
United States................................................... 7-4
Used Replacement Wheels..............................5-61
Using Cleaner on Fabric..................................5-81
Using HomeLink
ž...........................................2-43
Using RDS....................................3-67, 3-74, 3-84
Using Song List Mode.....................................3-90
V
Vehicle Identi®cation........................................5-88
Number (VIN).............................................5-88
Service Parts Identi®cation Label...................5-88
Vehicle Personalization....................................2-51
Memory Seat..............................................2-51
Vehicle Storage..............................................5-42
Vehicle............................................................ 4-5
Control........................................................ 4-5
Damage Warnings........................................... iv
Loading......................................................4-47
Symbols......................................................... iv
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