service GMC ACADIA 2009 Owner's Manual

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 5-49
andAccessories 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 nominalrim 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 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
Service and Appearance Care 5-51

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.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 specied 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 inated and
not overloaded. Excessive
speed, underination, or
excessive loading, either
separately or in combination,
can cause heat buildup and
possible tire failure.
5-52 Service and Appearance Care

Wheel Alignment and
Tire Balance
The tires and wheels on your vehicle
were aligned and balanced carefully
at the factory to give you the longest
tire life and best overall performance.
Adjustments to wheel alignment and
tire balancing will not be necessary
on a regular basis. However, if you
notice unusual tire wear or your
vehicle pulling to one side or the
other, the alignment might need to be
checked. If you notice your vehicle
vibrating when driving on a smooth
road, the tires and wheels might
need to be rebalanced. See your
dealer/retailer 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 (except some
aluminum wheels, which can
sometimes be repaired). See your
dealer/retailer if any of these
conditions exist.
Your dealer/retailer will know the
kind of wheel you need.
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, wheel nuts,
or Tire Pressure Monitor System
(TPMS) sensors, replace them only
with new GM original equipment
parts. This way, you will be sure to
have the right wheel, wheel bolts,
wheel nuts, and TPMS sensors 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.
SeeChanging a Flat Tire on
page 5-69for more information.
Service and Appearance Care 5-53

Used Replacement Wheels
{CAUTION
Putting a used wheel on the
vehicle is dangerous. You cannot
know how it has been used or
how far it has been driven. It
could fail suddenly and cause a
crash. If you have to replace a
wheel, use a new GM original
equipment wheel.
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.
(Continued)
CAUTION (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 nd
traction devices that will t, install
them on the front tires.
5-54 Service and Appearance Care

If a Tire Goes Flat
It is unusual for a tire to blowout
while you are driving, especially
if you maintain the tires properly.
SeeTires on page 5-35.Ifair
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 will
create 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 youwould 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 at, avoid further tire
and wheel damage by driving slowly
to a level place and stopping.
1. Turn on the hazard warning
ashers. SeeHazard Warning
Flashers on page 3-5.
2. Park the vehicle. Set the parking
brake rmly and put the shift
lever in P (Park).
3. Turn off the engine.
4. Inspect the at tire.{CAUTION
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
at 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 at tire.
This vehicle may come with a jack
and spare tire or a tire sealant
and compressor kit. To use the jack
and spare tire, seeChanging a
Flat Tire on page 5-69. To use the
tire sealant and compressor kit,
seeTire Sealant and Compressor
Kit on page 5-56.
Service and Appearance Care 5-55

Tire Sealant and
Compressor Kit
{CAUTION
Idling a vehicle in an enclosed
area with poor ventilation is
dangerous. Engine exhaust may
enter the vehicle. Engine exhaust
contains Carbon Monoxide (CO)
which cannot be seen or smelled.
It can cause unconsciousness
and even death. Never run the
engine in an enclosed area that
has no fresh air ventilation. For
more information, seeEngine
Exhaust on page 2-30.
{CAUTION
Over-inating a tire could cause
the tire to rupture and you or
others could be injured. Be sure to
read and follow the tire sealant and
compressor kit instructions and
inate the tire to its recommended
pressure. Do not exceed the
recommended pressure.
{CAUTION
Storing the tire sealant and
compressor kit or other equipment
in the passenger compartment of
the vehicle could cause injury. In a
sudden stop or collision, loose
equipment could strike someone.
Store the tire sealant and
compressor kit in its original
location.If this vehicle has a tire sealant and
compressor kit, there may not be a
spare tire, tire changing equipment,
and on some vehicles there may not
be a place to store a tire.
The tire sealant and compressor
can be used to temporarily
seal punctures up to
14inch (6 mm)
in the tread area of the tire. It can
also be used to inate an under
inated tire.
If the tire has been separated from
the wheel, has damaged sidewalls,
or has a large puncture, the tire
is too severely damaged for the tire
sealant and compressor kit to be
effective. SeeRoadside Assistance
Program on page 7-6.
Read and follow all of the tire
sealant and compressor kit
instructions.
5-56 Service and Appearance Care

This vehicle may have one of the following tire sealant and compressor kits. The kit includes:
Service and Appearance Care 5-57

5-58 Service and Appearance Care

A. Selector Switch (Sealant/Air or
Air Only)
B. On/Off Button
C. Pressure Gage
D. Pressure Deation Button
(If equipped)
E. Tire Sealant Canister
F. Sealant/Air Hose (Clear)
G. Air Only Hose (Black)
H. Power PlugTire Sealant
Read and follow the safe handling
instructions on the label adhered
to the sealant canister.
Check the tire sealant expiration
date on the sealant canister.
The sealant canister should be
replaced before its expiration date.
Replacement sealant canisters are
available at your local dealer/retailer.
See “Removal and Installation of the
Sealant Canister” following.
There is only enough sealant
toseal one tire. After usage, the
sealant canister and sealant/air hose
assembly must be replaced. See
“Removal and Installation of the
Sealant Canister” following.
Service and Appearance Care 5-59

Using the Tire Sealant and Compressor Kit to Temporarily Seal and Inate a Punctured Tire
Follow the directions closely for correct sealant usage.
5-60 Service and Appearance Care