wheel CHEVROLET IMPALA 2002 8.G Workshop Manual

6-33 Brake Wear
Your vehicle has four-wheel disc brakes.
Disc brake pads have built
-in wear indicators that
make a high
-pitched warning sound when the brake
pads are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving (except when you are pushing on the brake
pedal firmly).
CAUTION:
The brake wear warning sound means that soon
your brakes won't work well. That could lead to
an accident. When you hear the brake wear
warning sound, have your vehicle serviced.
NOTICE:
Continuing to drive with worn-out brake pads
could result in costly brake repair.
Some driving conditions or climates may cause a
brake squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
your brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to GM torque specifications.
Brake linings should always be replaced as complete
axle sets.
See ªBrake System Inspectionº in Section 7 of this manual
under Part C ªPeriodic Maintenance Inspections.º
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in pedal
travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you apply the brakes, with or without the
vehicle moving, your brakes adjust for wear.

6-44
To reset (calibrate) the system: The tire inflation
monitor system can be reset two ways. With the
ignition position at ON, pull the interior lamps
control to the ON and OFF settings three times.
It can also be reset through the radio using the
following steps:
1. Turn the ignition to ACC or ON and turn the
radio off.
2. Press and hold the TUNE DISP button on the radio for
at least five seconds until SETTINGS is displayed.
3. Press the SEEK PTYPE up or down arrow to scroll
through the main menu.
4. Scroll until TIRE MON appears on the display.
5. Press the 1 PREV or 2 NEXT button to enter the
submenu. RESET will be displayed.
6. Press the TUNE DISP button to reset. A chime will
be heard to verify the new setting and DONE will be
displayed for one second.
7. Once the monitor has been reset, scroll until EXIT
appears on the display.
8. Press the DISP button to exit programming. A chime
will be heard to verify exit.
The system completes the calibration process
during driving.The system normally takes 15 to 20 minutes of driving
in each of three speed ranges to ªlearnº tire pressures.
The speed ranges are 15 to 40 mph (25 to 65 km/h),
40 to 65 mph (65 to 105 km/h) and above 65 mph
(105 km/h). When learning is complete, the system
will alert you after two to eight minutes if a tire is 12 psi
(83 kPa) different from the other three tires. Detection
thresholds may be higher and detection times may be
longer on rough roads, curves and at high speeds. The
system is not capable of detection at speeds greater than
70 mph (110 km/h).
Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 miles
(10 000 to 13 000 km). Any time you notice unusual
wear, rotate your tires as soon as possible and check
wheel alignment. Also check for damaged tires or
wheels. See ªWhen It's Time for New Tiresº and
ªWheel Replacementº later in this section for
more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The first
rotation is the most important. See ªScheduled
Maintenance Servicesº in the Index for scheduled
rotation intervals.

6-45
When rotating your tires, always use the correct rotation
pattern shown here.
Don't include the compact spare tire in your
tire rotation.
After the tires have been rotated, adjust the front and
rear inflation pressures as shown on the Tire
-Loading
Information label. Reset the tire inflation monitor.
See ªResetting the Tire Inflation Monitorº in the
Index. Make certain that all wheel nuts are properly
tightened. See ªWheel Nut Torqueº in the Index.
CAUTION:
Rust or dirt on a wheel, or on the parts to which
it is fastened, can make wheel nuts become loose
after a 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 you need to, to get all the rust or dirt off. See
ªChanging a Flat Tireº in the Index.

6-47
CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
or types (radial and bias
-belted tires), the vehicle
may not handle properly, and you could have a
crash. Using tires of different sizes may also cause
damage to your vehicle. Be sure to use the same
size and type tires on all wheels.
It's all right to drive with your compact spare,
though. It was developed for use on your vehicle.
CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim flanges 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 your vehicle.
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, 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
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.

6-48
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 (1 1/2) 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.
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 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 inflated and
not overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.

6-49 Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at the factory to give you the longest tire life
and best overall performance.
Scheduled wheel alignment and wheel balancing are
not needed. However, if you notice unusual tire wear or
your vehicle pulling one way or the other, the alignment
may need to be reset. If you notice your vehicle
vibrating when driving on a smooth road, your wheels
may need to be rebalanced.
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 if any of these conditions exist.
Your dealer 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
or wheel nuts, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts and wheel nuts 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.

6-50
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 ªChanging a Flat Tireº in the Index for
more information.
Used Replacement Wheels
CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can't know how it's been used
or how far it's 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
NOTICE:
Use tire chains only where legal and only when
you must. Use only SAE Class ªSº 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 securely
fastened. 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.

6-57
Cleaning Aluminum Wheels
(If Equipped)
Keep your wheels clean using a soft clean cloth with
mild soap and water. Rinse with clean water. After
rinsing thoroughly, dry with a soft clean towel. A wax
may then be applied.
The surface of these wheels is similar to the painted
surface of your vehicle. Don't use strong soaps,
chemicals, abrasive polishes, abrasive cleaners, cleaners
with acid or abrasive cleaning brushes on them because
you could damage the surface. Do not use chrome polish
on aluminum wheels.
Don't take your vehicle through an automatic car wash
that has silicon carbide tire cleaning brushes. These
brushes can also damage the surface of these wheels.
Cleaning Tires
To clean your tires, use a stiff brush with a tire cleaner.
NOTICE:
When applying a tire dressing always take care to
wipe off any overspray or splash from all painted
surfaces on the body or wheels of the vehicle.
Petroleum
-based products may damage the paint
finish and tires.
Sheet Metal Damage
If your vehicle is damaged and requires sheet metal
repair or replacement, make sure the body repair shop
applies anti
-corrosion material to the parts repaired or
replaced to restore corrosion protection.
Original manufacturer replacement parts will provide
the corrosion protection while maintaining the warranty.

6-63
Mini Fuses Description
CIG/AUX Accommodated
Device (Accessory)
BCM Body Control Module (Accessory)
SRS Supplemental Restraint System
ABS/PCM Anti
-Lock Brake System,
Powertrain Control Module, Brake
Switch, Crank Relay, Canister
Vent Solenoid (Run, Crank)
STOP Brake Lamps, Body Control
Module (Run, Crank)
TURN SIGNAL Turn Signal Flashers
CRUISE Cruise Control Steering
Column Controls
AC/CRUISE HVAC Temp Door Motors &
Module, Cruise Control Module
A/C FAN HVAC Blower
STR COL Steering Wheel LightingMini Fuses Description
DR LK Body Control Module,
Door Lock Controls
PWR MIR Power Mirrors
CLSTR/BCM Cluster, Body Control Module,
Data Link Connector (Battery),
TrapAlert
System
LH HTD
ST/BCMDriver's Heated Seat, Body
Control Module, Battery
Controlled Loads
Circuit Breaker Description
RETAINED
ACCESSORY
PWR BRKRPower Window, Sunroof Breaker
Circuit Relay Description
HEADLAMP
RELAYHeadlamp Relay
RETAINED
ACCESSORY
PWR RELAYRetained Accessory Power Relay

6-69
Engine Oil with Filter
3400 (Code E) V6 4.3 quarts (4.1 L). . . . . . . . . . . .
3800 (Code K) V6 4.3 quarts (4.1 L). . . . . . . . . . . .
Fuel Tank17.0 U.S. gallons (64.0 L) . . . . . . . . . . . .
Wheel Nut Torque100 lb
-ft (140 N´m) . . . . . . . . . .
All capacities are approximate. When adding, be sure
to fill to the approximate level, as recommended in this
manual. See ªRecommended Fluids and Lubricantsº
in the Index.
Engine Specifications
3400 (LA1) V6 Engine
Type V6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VIN Code E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Displacement 204 CID. . . . . . . . . . . . . . . . . . . . . . . .
Firing Order 1
-2-3-4-5-6 . . . . . . . . . . . . . . . . . . . . . .
3800 (L36) V6 Engine
Type V6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VIN Code K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Displacement 231 CID. . . . . . . . . . . . . . . . . . . . . . . .
Firing Order 1
-6-5-4-3-2 . . . . . . . . . . . . . . . . . . . . . .
Air Conditioning
Refrigerant Capacity
If you do your own service work, you'll need the proper
service manual. See ªDoing Your Own Service Workº in
the Index for additional information. It is recommended
that service work on your air conditioning system be
performed by a qualified technician.
Air Conditioning
Refrigerant R±134a 2.3 lbs. (1.09 kg). . . . . . . . . . .
Use Refrigerant R134a System