service CHEVROLET IMPALA 2003 8.G Repair Manual

Notice:
·Using the wrong ¯uid can badly damage brake
system parts. For example, just a few drops of
mineral-based oil, such as engine oil, in your
brake system can damage brake system
parts so badly that they'll have to be replaced.
Don't let someone put in the wrong kind of ¯uid.
·If you spill brake ¯uid on your vehicle's painted
surfaces, the paint ®nish can be damaged. Be
careful not to spill brake ¯uid on your vehicle. If
you do, wash it off immediately. See
ªAppearance Careº in the Index.
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 ®rmly).
{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 ®rst 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 speci®cations.
Brake linings should always be replaced as complete
axle sets.
See
Brake System Inspection on page 6-15.
5-47

11. Try to start the vehicle that had the dead battery. If
it won't start after a few tries, it probably needs
service.
Notice:Damage to your vehicle may result from
electrical shorting if jumper cables are removed
incorrectly. To prevent electrical shorting, take care
that the cables don't touch each other or any
other metal. The repairs wouldn't be covered by
your warranty.
A. Heavy, Unpainted Metal Engine Part
B. Good Battery or Remote Positive (+) Terminal
C. Dead Battery or Remote Positive (+) TerminalTo disconnect the jumper cables from both vehicles, do
the following:
1. Disconnect the black negative (-) cable from the
vehicle that had the dead battery.
2. Disconnect the black negative (-) cable from the
vehicle with the good battery.
3. Disconnect the red positive (+) cable from the
vehicle with the good battery.
4. Disconnect the red positive (+) cable from the other
vehicle.
5. Return the remote positive (+) terminal cover to its
original position.
Jumper Cable Removal
5-54

Headlamp Aiming
If your vehicle is damaged in an accident, the headlamp
aim may be affected. Aim adjustment to the low beam
may be necessary if it is difficult to see lane markers (for
horizontal aim), or if oncoming drivers ¯ash their high
beams at you (for vertical aim). If you believe your
headlamps need to be re-aimed, we recommend that
you take your vehicle to the dealer for service. However,
it is possible for you to re-aim your headlamps by
following the procedure in the service manual for
your vehicle.
Notice:To make sure your headlamps are aimed
properly, read all the instructions before beginning.
Failure to follow these instructions could cause
damage to headlamp parts.
5-55

Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer. If you ever have questions
about your tire warranty and where to obtain service,
see your Chevrolet Warranty booklet for details.
{CAUTION:
Poorly maintained and improperly used tires
are dangerous.
·Overloading your tires can cause
overheating as a result of too much
friction. You could have an air-out and a
serious accident. See ªLoading Your
Vehicleº in the Index.
CAUTION: (Continued)
CAUTION: (Continued)
·
Underin¯ated tires pose the same danger
as overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked
when your tires are cold.
·Overin¯ated tires are more likely to be cut,
punctured or broken by a sudden impact
Ð such as when you hit a pothole. Keep
tires at the recommended pressure.
·Worn, old tires can cause accidents. If
your tread is badly worn, or if your tires
have been damaged, replace them.
5-61

Tire Inspection and Rotation
Tires should be rotated every 7,500 miles (12 500 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
When It Is Time
for New Tires on page 5-66andWheel Replacement
on page 5-69for more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The ®rst rotation
is the most important. See ªPart A: Scheduled
Maintenance Services,º in Section 6, for scheduled
rotation intervals.
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 in¯ation pressures as shown on the Tire-Loading
Information label.
Reset the Tire In¯ation Monitor System. See
Tire
Pressure Monitor System on page 5-63.
Make certain that all wheel nuts are properly tightened.
See ªWheel Nut Torqueº under
Capacities and
Speci®cations on page 5-103.
{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.
5-65

Buying New Tires
To ®nd out what kind and size of tires you need, look at
the Tire-Loading Information label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Speci®cation (TPC Spec)
number on each tire's sidewall. When you get new tires,
get ones with that same TPC Spec number. That way
your vehicle will continue to have tires that are designed
to give proper endurance, handling, speed rating,
traction, ride and other things during normal service on
your vehicle. If your tires have an all-season tread
design, the TPC number will be followed by an ªMSº (for
mud and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial) as your original tires.{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 temporarily, it was developed
for use on your vehicle. See ªCompact Spare
Tireº in the index.
{CAUTION:
If you use bias-ply tires on your 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 your vehicle.
5-67

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.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a speci®ed 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 signi®cantly 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 speci®ed 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.
5-68

Vehicle Identi®cation
Vehicle Identi®cation Number (VIN)
This is the legal identi®er for your vehicle. It appears on
a plate in the front corner of the instrument panel, on
the driver's side. You can see it if you look through the
windshield from outside your vehicle. The VIN also
appears on the Vehicle Certi®cation and Service Parts
labels and the certi®cates of title and registration.
Engine Identi®cation
The 8th character in your VIN is the engine code. This
code will help you identify your engine, speci®cations
and replacement parts.
Service Parts Identi®cation Label
You'll ®nd this label on the inside of your trunk lid. It's
very helpful if you ever need to order parts. On this
label is:
·your VIN,
·the model designation,
·paint information and
·a list of all production options and special
equipment.
Be sure that this label is not removed from the vehicle.
5-93

Maintenance Schedule......................................6-2
Introduction...................................................6-2
Your Vehicle and the Environment....................6-2
Maintenance Requirements..............................6-2
How This Section is Organized.........................6-3
Part A: Scheduled Maintenance Services...........6-4
Using Your Maintenance Schedule....................6-4
Scheduled Maintenance...................................6-5
Part B: Owner Checks and Services................6-10
At Each Fuel Fill..........................................6-10
At Least Once a Month.................................6-10
At Least Twice a Year...................................6-11At Least Once a Year...................................6-11
Part C: Periodic MaintenanceInspections.........6-14
Steering, Suspension and Front Drive Axle
Boot and Seal Inspection............................6-14
Exhaust System Inspection............................6-14
Fuel System Inspection..................................6-15
Engine Cooling System Inspection...................6-15
Throttle System Inspection.............................6-15
Brake System Inspection................................6-15
Part D: Recommended Fluids and Lubricants. . . .6-16
Part E: Maintenance Record...........................6-17
Section 6 Maintenance Schedule
6-1

How This Section is Organized
This maintenance schedule is divided into ®ve parts:
ªPart A: Scheduled Maintenance Servicesºexplains
what to have done and how often. Some of these
services can be complex, so unless you are technically
quali®ed and have the necessary equipment, you
should let your GM dealer's service department do
these jobs.
Your GM dealer has GM-trained and supported service
people that will perform the work using genuine
GM parts.
{CAUTION:
Performing maintenance work on a vehicle can
be dangerous. In trying to do some jobs, you
can be seriously injured. Do your own
maintenance work only if you have the
required know-how and the proper tools and
equipment for the job. If you have any doubt,
have a quali®ed technician do the work.
If you want to get the service information, see
Service
Publications Ordering Information on page 7-11.ªPart B: Owner Checks and Servicesºtells you what
should be checked and when. It also explains what
you can easily do to help keep your vehicle in
good condition.
ªPart C: Periodic MaintenanceInspectionsºexplains
important inspections that your dealer's service
department can perform for you.
ªPart D: Recommended Fluids and Lubricantsºlists
some recommended products necessary to help
keep your vehicle properly maintained. These products,
or their equivalents, should be used whether you do
the work yourself or have it done.
ªPart E: Maintenance Recordºis a place for you
to record and keep track of the maintenance performed
on your vehicle. Keep your maintenance receipts.
They may be needed to qualify your vehicle for
warranty repairs.
6-3