2004 CHEVROLET CLASSIC service

When to Check
Check your tires once a month or more.
Don’t forget your compact spare tire. It should be at
60 psi (420 kPa).
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated. Check
the tire’s inflation pressure when the tires are cold.
Cold means your vehicle has been sitting for at least
three hours or driven no more than 1 mile (1.6 km).
Remove the valve cap from the tire valve stem. Press
the tire gage firmly onto the valve to get a pressure
measurement. If the cold tire inflation pressure matches
the recommended pressure on the Tire and Loading
Information label, no further adjustment is necessary. If
the inflation pressure is low, add air until you reach
the recommended amount.
If you overfill the tire, release air by pushing on the
metal stem in the center of the tire valve. Recheck the
tire pressure with the tire gage.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and
moisture.
Tire Inspection and Rotation
Tires should be rotated every 5,000 to 8,000 miles
(8 000 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. SeeWhen It Is Time
for New Tires on page 5-62andWheel Replacement
on page 5-65for 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. SeePart A: Scheduled
Maintenance Services on page 6-4, for scheduled
rotation intervals.
5-60

When It Is Time for New Tires
One way to tell when it’s
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.
You need a new tire if any of the following statements
are true:
•You can see the indicators at three or more places
around the tire.
•You can see cord or fabric showing through the
tire’s rubber.
•The tread or sidewall is cracked, cut or snagged
deep enough to show cord or fabric.
•The tire has a bump, bulge or split.
•The tire has a puncture, cut or other damage that
can’t be repaired well because of the size or
location of the damage.
Buying New Tires
To find out what kind and size of tires you need, look at
the tire and loading information label. For an example
of this label and its location, seeLoading Your Vehicle
on page 4-32.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specification (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,
load range, 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 “MS” (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.
5-62

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 (1.5) 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 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.
5-64

Vehicle Identication
Vehicle Identication Number (VIN)
This is the legal identifier 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 Certification and Service Parts
labels and the certificates of title and registration.
Engine Identication
The 8th character in your VIN is the engine code. This
code will help you identify your engine, specifications
and replacement parts.
Service Parts Identication Label
You’ll find this label on the bottom of your spare
tire cover. 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.
5-88

Maintenance Schedule......................................6-2
Introduction...................................................6-2
Maintenance Requirements..............................6-2
Your Vehicle and the Environment....................6-2
How This Section is Organized.........................6-3
Part A: Scheduled Maintenance Services...........6-4
Using Your Maintenance Schedule....................6-4
Selecting the Right Schedule...........................6-5
Short Trip/City Scheduled Maintenance..............6-6
Long Trip/Highway Scheduled Maintenance......6-12
Part B: Owner Checks and Services................6-16
At Each Fuel Fill..........................................6-16
At Least Once a Month.................................6-16At Least Twice a Year...................................6-17
At Least Once a Year...................................6-17
Part C: Periodic MaintenanceInspections.........6-20
Steering, Suspension and Front Drive Axle
Boot and Seal Inspection............................6-20
Exhaust System Inspection............................6-20
Fuel System Inspection..................................6-20
Engine Cooling System Inspection...................6-21
Throttle System Inspection.............................6-21
Brake System Inspection................................6-21
Part D: Recommended Fluids and Lubricants......6-22
Part E: Maintenance Record...........................6-23
Section 6 Maintenance Schedule
6-1

How This Section is Organized
This maintenance schedule is divided into five parts:
“Part A: Scheduled Maintenance Services”explains
what to have done and how often. Some of these
services can be complex, so unless you are technically
qualified 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 qualied technician do the work.
If you want to get the service information, seeService
Publications Ordering Information on page 7-11.“Part B: Owner Checks and Services”tells you what
should be checked and when. It also explains what
you can easily do to help keep your vehicle in good
condition.
“Part C: Periodic MaintenanceInspections”explains
important inspections that your dealer’s service
department can perform for you.
“Part D: Recommended Fluids and Lubricants”lists
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.
“Part E: Maintenance Record”is 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

Part A: Scheduled Maintenance
Services
In this part are scheduled maintenance services which
are to be performed at the mileage intervals specified.
Using Your Maintenance Schedule
We at General Motors want to keep your vehicle in good
working condition. But we do not know exactly how
you will drive it. You may drive short distances only a
few times a week. Or you may drive long distances
all the time in very hot, dusty weather. You may
use your vehicle in making deliveries. Or you may drive
it to work, to do errands or in many other ways.
Because of the different ways people use their vehicles,
maintenance needs may vary. You may need more
frequent checks and replacements. So please read the
following and note how you drive. If you have
questions on how to keep your vehicle in good condition,
see your dealer.This part tells you the maintenance services you should
have done and when to schedule them.
When you go to your dealer for your service needs, you
will know that GM-trained and supported service
people will perform the work using genuine GM parts.
The proper fluids and lubricants to use are listed in
Part D. Make sure whoever services your vehicle uses
these. All parts should be replaced and all necessary
repairs done before you or anyone else drives the
vehicle.
These schedules are for vehicles that:
•carry passengers and cargo within recommended
limits. You will find these on the tire and loading
information label. SeeLoading Your Vehicle
on page 4-32.
•are driven on reasonable road surfaces within legal
driving limits.
•use the recommended fuel. SeeGasoline Octane
on page 5-4.
6-4

Selecting the Right Schedule
First you’ll need to decide which of the two schedules is
right for your vehicle. Here’s how to decide which
schedule to follow:
Short Trip/City Denition
Follow the Short Trip/City Scheduled Maintenance if any
one of these conditions is true for your vehicle:
•Most trips are less than 5 miles (8 km). This is
particularly important when outside temperatures
are below freezing.
•Most trips include extensive idling (such as frequent
driving in stop-and-go traffic).
•You frequently tow a trailer or use a carrier on top
of your vehicle.
•If the vehicle is used for delivery service, police,
taxi or other commercial application.
One of the reasons you should follow this schedule if
you operate your vehicle under any of these conditions
is that these conditions cause engine oil to break
down sooner.
Short Trip/City Intervals
Every 3,000 Miles (5 000 km):Engine Oil and Filter
Change (or 3 months, whichever occurs first).
Every 6,000 Miles (10 000 km):Tire Rotation.
Every 15,000 Miles (25 000 km):Engine Air Cleaner
Filter Inspection.
Every 30,000 Miles (50 000 km):Engine Air Cleaner
Filter Replacement.
Every 50,000 Miles (83 000 km):Automatic Transaxle
Service (severe conditions only).
Every 100,000 Miles (166 000 km):Spark Plug Wire
Inspection. Spark Plug Replacement.
Every 150,000 Miles (240 000 km):Cooling System
Service (or every 60 months, whichever occurs
first). Engine Accessory Drive Belt Inspection.
These intervals only summarize maintenance services.
Be sure to follow the complete scheduled maintenance
on the following pages.
6-5