
Black plate (57,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Vehicle Care 10-57
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 TireQuality 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.
All Passenger Car Tires Must
Conform to Federal Safety
Requirements In Addition
To These Grades.
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 (1½) 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.

Black plate (58,1)GMC Acadia/Acadia Denali Owner Manual - 2011
10-58 Vehicle Care
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. 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 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.

Black plate (59,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Vehicle Care 10-59
Wheel Alignment and Tire
Balance
The tires and wheels were
aligned and balanced at the
factory to provide the longest tire
life and best overall performance.
Adjustments to wheel alignment and
tire balancing will not be necessary
on a regular basis. However, check
the alignment if there is unusual tire
wear or if the vehicle is pulling to
one side or the other. If the vehicle
vibrates when driving on a smooth
road, the tires and wheels might
need to be rebalanced. See your
dealer for proper diagnosis.
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.
Some aluminum wheels can be
repaired. See your dealer if any
of these conditions exist.
Your dealer will know the kind of
wheel that is needed.
Each new wheel should have
the same load-carrying capacity,
diameter, width, offset, and be
mounted the same way as the
one it replaces.
Replace wheels, wheel bolts,
wheel nuts, or Tire Pressure Monitor
System (TPMS) sensors with new
GM original equipment parts.{WARNING
Using the wrong replacement
wheels, wheel bolts, or wheel
nuts can be dangerous. It could
affect the braking and handling
of the vehicle. Tires can lose air,
and cause loss of control, causing
a crash. 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 If a Tire Goes Flat on
page 10‑61 for more information.

Black plate (60,1)GMC Acadia/Acadia Denali Owner Manual - 2011
10-60 Vehicle Care
Used Replacement Wheels
{WARNING
Replacing a wheel with a used
one is dangerous. How it has
been used or how far it has been
driven may be unknown. It could
fail suddenly and cause a crash.
When replacing wheels, use a
new GM original equipment
wheel.
Tire Chains
{WARNING
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.(Continued)
WARNING (Continued)
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, readjust
or remove the device if it is
contacting the vehicle, and do not
spin the vehicle's wheels. If you
do find traction devices that will
fit, install them on the front tires.

Black plate (61,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Vehicle Care 10-61
If a Tire Goes Flat
It is unusual for a tire to blowout,
especially if the tires are maintained
properly. See Tires. If air goes out of
a tire, it is much more likely to leak
out slowly. But if there is ever a
blowout, here are a few tips about
what to expect and what to do:
If a front tire fails, the flat tire
creates 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 off the
road, if possible.AA rear blowout, particularly on a
curve, acts much like a skid and
may require the same correction
as used in a skid. Stop pressing
the accelerator pedal and steer to
straighten the vehicle. It may be
very bumpy and noisy. Gently
brake to a stop, well off the road,
if possible.
{WARNING
Driving on a flat tire will cause
permanent damage to the tire.
Re-inflating a tire after it has
been driven on while severely
underinflated or flat may cause
a blowout and a serious crash.
Never attempt to re-inflate a tire
that has been driven on while
severely underinflated or flat.
Have your dealer or an authorized
tire service center repair or
replace the flat tire as soon
as possible.
{WARNING
Lifting a vehicle and getting
under it to do maintenance or
repairs is dangerous without the
appropriate safety equipment and
training. If a jack is provided with
the vehicle, it is designed only for
changing a flat tire. If it is used for
anything else, you or others could
be badly injured or killed if the
vehicle slips off the jack. If a jack
is provided with the vehicle, only
use it for changing a flat tire.
If a tire goes flat, avoid further tire
and wheel damage by driving slowly
to a level place, well off the road,
if possible. Turn on the hazard
warning flashers. See Hazard
Warning Flashers on page 6‑3.

Black plate (82,1)GMC Acadia/Acadia Denali Owner Manual - 2011
10-82 Vehicle Care
Have the hoist shaft assembly
inspected as soon as you can.
You will not be able to store a spare
tire using the hoist assembly until it
has been repaired or replaced.
Compact Spare Tire
{WARNING
Driving with more than one
compact spare tire at a time
could result in loss of braking
and handling. This could lead
to a crash and you or others
could be injured. Use only one
compact spare tire at a time.
The compact spare tire, if the
vehicle has one, was fully inflated
when the vehicle was new, however,
it can lose air after a time. Check
the inflation pressure regularly.
It should be 60 psi (420 kPa). After installing the compact
spare on the vehicle, stop as
soon as possible and make sure
the spare tire is correctly inflated.
The compact spare is made to
perform well at speeds up to
65 mph (105 km/h) for distances up
to 3,000 miles (5 000 km), so you
can finish your trip and have the
full-size tire repaired or replaced
at your convenience. Of course,
it is best to replace the spare with
a full-size tire as soon as possible.
The spare tire will last longer and be
in good shape in case it is needed
again.
Notice:
When the compact
spare is installed, do not take
the vehicle through an automatic
car wash with guide rails. The
compact spare can get caught on
the rails which can damage the
tire, wheel and other parts of the
vehicle. Do not use the compact spare on
other vehicles.
And do not mix the compact spare
tire or wheel with other wheels or
tires. They will not fit. Keep the
spare tire and its wheel together.
The All-Wheel Drive (AWD) system
will be automatically disabled
when you use the compact spare.
To restore the AWD and prevent
excessive wear on the clutch in
your AWD, replace the compact
spare tire with a full-size tire as
soon as possible.
Notice:
Tire chains will not fit the
compact spare. Using them can
damage the vehicle and can
damage the chains too. Do not
use tire chains on the compact
spare.

Black plate (89,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Vehicle Care 10-89
Once the destination is reached:
1. Set the parking brake.
2. Reinstall the fuses in theunderhood fuse block.
3. Shift the transmission to P (Park), turn the ignition to
LOCK/OFF and remove the
key from the ignition.
4. Disconnect the vehicle from the towing vehicle.
Notice: Do not tow a vehicle
with the front drive wheels on
the ground if one of the front tires
is a compact spare tire. Towing
with two different tire sizes on the
front of the vehicle can cause
severe damage to the
transmission.Dolly Towing
(All-Wheel‐Drive Vehicles)
All-wheel‐drive vehicles must not
be towed with two wheels on the
ground. To properly tow these
vehicles, they should be placed on
a platform trailer with all four wheels
off of the ground or dinghy towed
from the front.
Dolly Towing
(Front-Wheel‐ Drive
Vehicles Only)
To tow a front-wheel‐drive vehicle
from the front with two wheels on
the ground:
1. Put the front wheels on a dolly.
2. Move the shift lever to P (Park).
3. Set the parking brake.
4. Clamp the steering wheel in a
straight-ahead position with a
clamping device designed for
towing.

Black plate (94,1)GMC Acadia/Acadia Denali Owner Manual - 2011
10-94 Vehicle Care
Tires
Use a stiff brush with tire cleaner to
clean the tires.
Notice:Using petroleum-based
tire dressing products on the
vehicle may damage the paint
finish and/or tires. When applying
a tire dressing, always wipe off
any overspray from all painted
surfaces on the vehicle.
Sheet Metal Damage
If the vehicle is damaged and
requires sheet metal repair or
replacement, make sure the body
repair shop applies anti-corrosion
material to parts repaired or
replaced to restore corrosion
protection.
Original manufacturer replacement
parts will provide the corrosion
protection while maintaining the
vehicle warranty.
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 major repair expense.
Minor chips and scratches can be
repaired with touch-up materials
available from your dealer. 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, corrosion and rust can
develop 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 debris can collect.
Dirt packed in close areas of the
frame should be loosened before
being flushed. Your dealer or an
underbody car washing system
can do this.
Chemical Paint Spotting
Some weather and atmospheric
conditions can create a chemical
fallout. Airborne pollutants can fall
upon and attack painted surfaces
on the vehicle. This damage can
take two forms: blotchy, ring-shaped
discolorations, and small, irregular
dark spots etched into the paint
surface.