GMC ACADIA 2008 Owner's Manual

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.
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.
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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.
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.
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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 5-72for more
information.
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Used Replacement Wheels
{CAUTION:
Putting a used wheel on your 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
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 is contacting your vehicle, and do
not spin your vehicle’s wheels. If you do nd
traction devices that will t, install them on the
front tires.
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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.{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
The jack provided with your vehicle 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. Use the jack provided with your
vehicle only for changing a at tire.
If a tire goes at, the next part shows how to use the
jacking equipment to change a at tire safely.
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Changing a Flat Tire
If a tire goes at, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your vehicle’s
hazard warning ashers. SeeHazard Warning Flashers
on page 3-6for more information.{CAUTION:
Changing a tire can be dangerous. The vehicle
can slip off the jack and roll over or fall on you
or other people. You and they could be badly
injured or even killed. Find a level place to
change your tire. To help prevent the vehicle
from moving:
1. Set the parking brake rmly.
2. Put the shift lever in PARK (P).
3. Turn off the engine and do not restart
while the vehicle is raised.
4. Do not allow passengers to remain in the
vehicle.
To be even more certain the vehicle will not
move, you should put blocks at the front and
rear of the tire farthest away from the one
being changed. That would be the tire, on the
other side, at the opposite end of the vehicle.
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When your vehicle has a at tire, use the following
example as a guide to assist you in the placement of
wheel blocks.
The following information tells you how to use the jack
and change a tire.
Removing the Spare Tire and Tools
The tools needed to remove the spare tire are located
in the storage compartment on the driver side, at
the rear of the vehicle.
1. Open the jack storage compartment by squeezing
down on the latch tab and pulling the cover off.A. Tool Bag
B. Wing Bolt
C. Jack
2. Remove the wing bolt (B) by turning it
counterclockwise
3. Push the jack (C) up out of the holding bracket.
4. Turn the jack on its side, with the bottom facing
toward you.
5. Pull the jack straight out, bottom rst.
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The tools you will be using include the jack (A) and lug
wrench (B).
Removing the Spare Tire
The compact spare tire is located under the vehicle, in
front of the rear bumper. SeeCompact Spare Tire on
page 5-88for more information about the compact spare.A. Rear Convenience
Center
B. Lug wrench
C. Storage
Compartment
Cap HoleD. Hoist Shaft
E. Compact
Spare Tire
F. Retainer
G. Hoist Shaft
Assembly
1. Open the storage compartment door of the
convenience center that is nearest the liftgate.
2. Move the carpet cutout that is located through the
hole of the storage compartment.
3. Attach the lug wrench into the hoist shaft.
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4. Turn the lug wrench counterclockwise to lower the
spare tire to the ground. Continue turning the
wrench until the spare tire can be pulled out from
under the vehicle.
5. Tilt the retainer and slip it through the wheel
opening to remove the spare tire from the cable.
6. Turn the wrench clockwise to raise the cable back
up after removing the spare tire.
Do not store a full-size or a at road tire under the
vehicle. SeeStoring a Flat or Spare Tire and
Tools on page 5-84.To continue changing the at tire, seeRemoving the
Flat Tire and Installing the Spare Tire (Outlook) on
page 5-76.
If the spare tire will not lower, the secondary latch could
be engaged.
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Do the following to check the cable:
1. Check under the vehicle to see if the cable is
visible.
2. If it is not visible, seeSecondary Latch System on
page 5-81.
If it is visible, rst try to tighten the cable by turning
the lug wrench clockwise until you hear two
clicks or feel it skip twice. You cannot over-tighten
the cable.
3. Loosen the cable by turning the wrench
counterclockwise three or four turns.
4. If the spare tire did lower to the ground, continue
with Step 5 under “Removing the Spare Tire” listed
previously.
5. If you still cannot lower the spare tire to the ground,
seeSecondary Latch System on page 5-81.Removing the Flat Tire and
Installing the Spare Tire
1. Do a safety check before proceeding. SeeChanging
a Flat Tire on page 5-72for more information.
2. If the vehicle has a wheel cover, loosen the plastic
nut caps with the wheel wrench. They will not come
off. Then, using the at end of the wheel wrench,
pry along the edge of the cover until it comes off. Be
careful; the edges may be sharp. Do not try to
remove the cover with your bare hands.
Store the wheel cover securely in the rear of the
vehicle until you have the at tire repaired or
replaced.
If your vehicle has aluminum wheels, remove the
wheel nut caps using the wheel wrench.
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