traction control GMC ENVOY 2009 Owner's Guide

Different Size Tires and Wheels
If you add wheels or tires that are a different size than
your original equipment wheels and tires, this could
affect the way your vehicle performs, including its
braking, ride and handling characteristics, stability, and
resistance to rollover. Additionally, if your vehicle
has electronic systems such as anti-lock brakes, rollover
airbags, traction control, and electronic stability control,
the performance of these systems can be affected.
{CAUTION:
If you add different sized wheels, your vehicle may
not provide an acceptable level of performance and
safety if tires not recommended for those wheels
are selected. You may increase the chance that you
will crash and suffer serious injury. Only use GM
specic wheel and tire systems developed for your
vehicle, and have them properly installed by a GM
certied technician.
SeeBuying New Tires on page 5-70andAccessories
and Modifications on page 5-3for additional information.
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 (NHTSA),
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
(UTQG) 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.
5-72

Treadwear
The treadwear grade is a comparative rating based
on the wear rate of the tire when tested under
controlled conditions on a specied 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 signicantly 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 specied 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.
5-73

Tire Chains
{CAUTION:
Do not use tire chains. There is 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 the 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 the vehicle and tire size combination and
road conditions. Follow that manufacturer’s
instructions. To help avoid damage to the vehicle,
drive slowly, re-adjust or remove the device if it is
contacting the vehicle, and do not spin the wheels.
If you do nd traction devices that will t, install
them on the rear tires.
If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your vehicle’s tires properly.
If air goes out of a tire, it is much more likely to leak out
slowly. But if you should ever have a blowout, here
are a few tips about what to expect and what to do:
If a front tire fails, the at tire creates a drag that pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel rmly.
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
would 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.
5-76

Tires (cont.)
Inspection and Rotation................................5-68
Installing the Spare Tire................................5-92
Pressure Monitor Operation...........................5-64
Pressure Monitor System..............................5-63
Removing the Flat Tire.................................5-92
Removing the Spare Tire and Tools...............5-89
Secondary Latch System..............................5-97
Spare Tire................................................5-102
Storing a Flat or Spare Tire and Tools..........5-100
Tire Sealant and Compressor Kit...................5-77
Tire Sidewall Labeling..................................5-54
Tire Terminology and Denitions....................5-57
Uniform Tire Quality Grading.........................5-72
Wheel Alignment and Tire Balance.................5-74
Wheel Replacement.....................................5-74
When It Is Time for New Tires......................5-69
Towing
Recreational Vehicle.....................................4-38
Towing a Trailer..........................................4-46
Your Vehicle...............................................4-38
Traction
StabiliTrak
®System....................................... 4-6
Transmission
Fluid, Automatic...........................................5-21
Transmission Operation, Automatic....................2-25Trip Odometer................................................3-29
Turn and Lane-Change Signals.......................... 3-7
Turn Signal/Multifunction Lever........................... 3-7
U
Uniform Tire Quality Grading............................5-72
Universal Home Remote System.......................2-46
Operation...................................................2-47
V
Vehicle
Control........................................................ 4-3
Loading......................................................4-31
Running While Parked..................................2-38
Symbols......................................................... iii
Vehicle Customization, DIC..............................3-56
Vehicle Data Recording and Privacy..................7-16
Vehicle Identication
Number (VIN)............................................5-111
Service Parts Identication Label..................5-111
Ventilation Adjustment......................................3-26
Visors...........................................................2-15
Voltmeter Gage..............................................3-34
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