tires CHEVROLET IMPALA 2009 9.G Service Manual

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

Compact Spare Tire
{CAUTION:
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.
Although the compact spare tire was fully inated when
the vehicle was new, it can lose air after a time. Check
the ination pressure regularly. It should be 60 psi
(420 kPa).
After installing the compact spare on the vehicle, you
should stop as soon as possible and make sure the spare
tire is correctly inated. 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 nish
your trip and have the full-size tire repaired or replaced
where you want. You must calibrate the tire ination
monitor system after installing or removing the compact
spare. SeeTire Pressure Monitor System on page 5-62.The system may not work correctly when the compact
spare is installed on the vehicle. Of course, it’s best to
replace the spare with a full-size tire as soon as you can.
The spare will last longer and be in good shape in case
you need it 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 t. Keep the
spare tire and its wheel together.
Notice:Tire chains will not t the compact spare.
Using them can damage the vehicle and can damage
the chains too. Do not use tire chains on the compact
spare.
5-88

Tires
To clean the tires, use a stiff brush with tire cleaner.
Notice:Using petroleum-based tire dressing
products on the vehicle may damage the paint nish
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 nish
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/retailer. Larger
areas of nish damage can be corrected in your
dealer’s/retailer’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, oor pan,
and exhaust system even though they have corrosion
protection.
At least every spring, ush 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 ushed. Your
dealer/retailer 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.
Although no defect in the paint job causes this, we will
repair, at no charge to the owner, the surfaces of
new vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occurs rst.
5-95

Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil on page 5-17. Reset oil life
system. SeeEngine Oil Life System on page 5-20.An Emission Control
Service.••
Visually check for any leaks or damage.See footnote (k).••
Inspect engine air cleaner lter. If necessary, replace lter. SeeEngine Air
Cleaner/Filter on page 5-21.See footnote (m).•
Rotate tires and check ination pressures and wear. SeeTire Inspection and
Rotation on page 5-67and “Tire Wear Inspection” inAt Least Once a Month on
page 6-9.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid as
needed.••
Perform any needed additional services. See “Additional Required Services” in
this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transmission uid level and add uid as needed.•
Replace passenger compartment air lter, if equipped.See footnote (g).•
Inspect throttle system.See footnote (j).•
6-5

Engine Coolant Level Check
Check the engine coolant level and add DEX-COOL®
coolant mixture if necessary. SeeEngine Coolant
on page 5-28.
Windshield Washer Fluid Level Check
Check the windshield washer uid level in the windshield
washer uid reservoir and add the proper uid if
necessary.
At Least Once a Month
Tire Ination Check
Inspect the vehicle’s tires and make sure they are
inated to the correct pressures. Do not forget to check
the spare tire. SeeInflation - Tire Pressure on
page 5-60. Check to make sure the spare tire is stored
securely. SeeChanging a Flat Tire on page 5-76.
Tire Wear Inspection
Tire rotation may be required for high mileage highway
drivers prior to the Engine Oil Life System service
notication. Check the tires for wear and, if necessary,
rotate the tires. SeeTire Inspection and Rotation on
page 5-67.
At Least Once a Year
Starter Switch Check
{CAUTION:
When you are doing this inspection, the vehicle
could move suddenly. If the vehicle moves, you or
others could be injured.
1. Before starting this check, be sure there is enough
room around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. SeeParking Brake on page 2-26.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The vehicle
should start only in P (Park) or N (Neutral). If the
vehicle starts in any other position, contact
your dealer/retailer for service.
6-9