wheel CHEVROLET IMPALA 2009 9.G Workshop Manual

Reset the Tire Pressure Monitor System. SeeTire
Pressure Monitor Operation on page 5-63.
Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and Specifications on page 5-101.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the
vehicle. In an emergency, you can use a
cloth or a paper towel to do this; but be sure
to use a scraper or wire brush later, if
needed, to get all the rust or dirt off. See
Changing a Flat Tire on page 5-76.
When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions
inuence when you need new tires.
One way to tell when it
is time for new tires is to
check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of tread
remaining.
5-68

GM recommends replacing tires in sets of four.
This is because uniform tread depth on all tires will
help keep your vehicle performing most like it did
when the tires were new. Replacing less than a full
set of tires can affect the braking and handling
performance of your vehicle. SeeTire Inspection
and Rotation on page 5-67for information on
proper tire rotation.
{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different
sizes, brands, or types (radial and bias-belted
tires), the vehicle may not handle properly,
and you could have a crash. Using tires of
different sizes, brands, or types may also
cause damage to your vehicle. Be sure to
use the correct size, brand, and type of tires
on all wheels. It is all right to drive with your
compact spare temporarily, as it was
developed for use on your vehicle. See
Compact Spare Tire on page 5-88.
{CAUTION:
If you use bias-ply tires on the 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 the vehicle.
If you must replace your vehicle’s tires with those
that do not have a TPC Spec number, make
sure they are the same size, load range, speed
rating, and construction type (radial and
bias-belted tires) as your vehicle’s original tires.
Vehicles that have a tire pressure monitoring
system could give an inaccurate low-pressure
warning if non-TPC Spec rated tires are installed on
your vehicle. Non-TPC Spec rated tires may give a
low-pressure warning that is higher or lower than
the proper warning level you would get with TPC
Spec rated tires. SeeTire Pressure Monitor System
on page 5-62.
Your vehicle’s original equipment tires are listed
on the Tire and Loading Information Label.
SeeLoading the Vehicle on page 4-20, for more
information about the Tire and Loading Information
Label and its location on your vehicle.
5-70

Different Size Tires and Wheels
If you add wheels or tires that are a different size than
your original equipment wheels and tires, this may 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, antilock brakes, 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 5-69andAccessories
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.
5-71

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.
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. It should be noted that
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.
5-72

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 5-76for more
information.
5-73

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:
If your vehicle has P225/55R17 or P235/50R18
size tires, 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.
CAUTION: (Continued)
5-74

CAUTION: (Continued)
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 wheels.
If you do nd traction devices that will t, install
them on the front tires.
Notice:If your vehicle has a tire size other than
P225/55R17 or P235/50R18 size tires, use tire chains
only where legal and only when you must. Use only
SAE Class S-type chains that are the proper size for
your tires. Install them on the front tires and tighten
them as tightly as possible with the ends securelyfastened. Drive slowly and follow the chain
manufacturer’s instructions. If you can hear the
chains contacting your vehicle, stop and retighten
them. If the contact continues, slow down until it
stops. Driving too fast or spinning the wheels with
chains on will damage your vehicle.
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.
5-75

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. 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.
If a tire goes at, the next part shows how to use the
jacking equipment to change a at tire safely.
Changing a Flat Tire
If a tire goes at, avoid further tire and wheel damage
by driving slowly to a level place. Turn on the hazard
warning ashers. SeeHazard Warning Flashers on
page 3-6.
{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 P (Park).
3. Turn off the engine and do not restart while
the vehicle is raised.
4. Do not allow passengers to remain in the
vehicle.
CAUTION: (Continued)
5-76

CAUTION: (Continued)
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.
When the vehicle has a at tire (B), use the following
example as a guide to assist you in the placement
of wheel blocks (A).
A. Wheel Block
B. Flat Tire
The following information explains how to use the jack
and change a tire.
Removing the Spare Tire and Tools
The equipment you will need is located in the trunk.
1. Open the trunk. SeeTrunk on page 2-12.
2. Remove the convenience net if the vehicle has one.
3. Remove the spare tire cover.
4. Turn the wing nut counterclockwise and remove it.
5. Remove the compact spare tire.
5-77

6. Turn the nut holding the jack counterclockwise and
remove it. Then remove the jack and wrench.The tools you will need to change a tire include the
jack (A), extension and protection guide (B), and wheel
wrench (C).
5-78