2003 CHEVROLET ASTRO fuel

Usage
Rear/Heat and Air Conditioning
Relays
AIC Relay
(Rear Heat
and AIC)
Relay
Relay
A/C Enable
Relay
Upfitter-ACCY
Upfitter Accessory
Starter Enable Starter
Headlamps Relay
Fuel Pump
Relay Air
Conditioning
Headlamps
Fuel Pump
FuselCircuit
Usage
UPFITTER- Upfitter Battery Power Stud,
BATT Trailer Wiring Harness
UPFITTER- Upfitter Accessory Relay
ACCY
Spare Not used
Spare Not used
Breaker FuselCircuit
Breaker
Spare
ECM-1 B
HORN
AIC COMP
RR HTR/AC ATC
FRT HVAC
ENG-I
IGN-E
ECM-I
Blank
RH HDLMP
LH Headlamp
Blank
Blank
Usage
Not used
Fuel Pump Relay and Motor, VCM,
Oil Pressure Switch/Sender
Horn Relay and Horn
Air Conditioning Enable Relay and
Compressor
Rear Heater and Air Conditioning
Active Transfer Case-L Van
Front Heater and Air Conditioning
Oxygen Sensors, Camshaft Position
Sensor, Mass Air Flow Sensor,
Evaporative Emission Canister
Vent Solenoid
Air Conditioning Enable Relay Coil
Fuel Injectors
1-6, Crankshaft
Position Sensot, VCM, Coil Driver
Module (EST), Ignition Coil
Not Used
Right Headlamp
Left Headlamp
Not Used
Not Used
5-97

Capacities and Specifications
Please refer to Part D: Recommended Nuids and Lubricants on page 6-32 for more information. See refrigerant
charge label under the hood for charge capacity information and requirements.
Engine Specifications
“Vortec” 4300 V6 MFI* 1-6-5-4-3-2
I *Micro Fuel IniectionTire Pressures - See Loadina Your Vehicle on mae 4-29. I
Capacities and Specifications
I Capacities I
Fuel Tank I 27.0 gallons I 101.8 L
Transmission Fluid (Drain and Refill) 4.7 L 5.0 quarts
5-99

Normal Maintenance Replacement Parts
Replacement part numbers listed in this section are based on the latest information available at the time of printing,
and are subject to change.
If a part listed in this manual is not the same as the part used in your vehicle when it
was built, or
if you have any questions, please contact your GM truck dealer.
Part Number
I Engine Oil Filter
PF47*
Positive Crankcase Ventilation (PCV) Valve CV769C*
I Spark Plugs
41 -932*
I Fuel Filter
GF481*
Wiper Blades (Front)
Type
Length Trico 221 101 58
18 inches (45.7 cm)
Wiper Blades (Rear)
Type
Length Trico 22 1 54396
14 inches (35.5 cm)
5-1 01

Section 6 Maintenance Schedule
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
Selecting the Right Schedule
........................... 6-5
Short Trip/City Scheduled Maintenance
.............. 6.7
Long Trip/Highway Scheduled Maintenance
...... 6.18
Part B: Owner Checks and Services
................ 6.26
At Each Fuel Fill
.......................................... 6-26
At Least Once a Month
................................. 6.26
At Least Twice a Year
................................... 6.26 At
Least Once a Year
................................... 6-27
Part C: Periodic Maintenance inspections
......... 6.30
Steering. Suspension and Front Drive Axle
Boot and Seal Inspection
............................ 6.30
Exhaust System Inspection
............................ 6.30
Fuel System Inspection
.................................. 6.30
Engine Cooling System Inspection
................... 6.30
Throttle System Inspection
............................ -6-31
Transfer Case and Front Axle
(All-Wheel Drive) Inspection
....................... -6-31
Brake System Inspection
................................ 6.31
Part D: Recommended Fluids
and Lubricants
.......................................... 6.32
Part E: Maintenance Record
........................... 6.34
6-
1

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 help you to keep
your vehicle in good working condition. But we don’t
know exactly how you’ll 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 all the different ways people use their
vehicles, maintenance needs vary. You may need more
frequent checks and replacements.
So please read
the following and note how you drive.
If you have any
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 you should schedule them.
When you go to your dealer for your service needs,
you’ll know that GM-trained and supported sewice
people will perform the work using GM parts.
The proper fluids and lubricants to use are listed in
Part D. Make sure whoever services your vehicle uses
them.
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 limits on your vehicle’s
CertificationRire label. See
Loading Your Vehicle
on page
4-29.
are driven on reasonable road surfaces within
driving limits.
use the recommended fuel. See Gasoline Octane
on page
5-5.
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 Definition
Follow the Short Trip/City Scheduled Maintenance if any
one of these conditions is true for your vehicle:
e
e
e
e
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). Chassis
Lubrication (or
3 months, whichever occurs first).
Drive Axle Fluid Check.
Every 6,000 Miles (IO 000 km): Tire Rotation.
Every 15,000 Miles (25 000 km): Engine Air
Cleaner Filter Inspection,
if driving in dusty conditions.
Front Wheel Bearing Repack (two-wheel drive only)
(or at each brake relining, whichever occurs first).
Automatic Transmission Service (severe conditions only).
Every 30,000 Miles (50 000 km): Engine Air Cleaner
Filter Replacement. Fuel Filter Replacement.
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (normal conditions).
Transfer Case Fluid Change.
Every 100,000 Miles (166 000 km): Spark Plug Wire
Inspection. Spark Plug Replacement. Positive
Crankcase Ventilation (PCV) Valve Inspection.
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

Long Trip/Highway Definition
Follow this scheduled maintenance only if none of
the conditions from the Short Trip/City Scheduled
Maintenance are true. Do not use this schedule
if the
vehicle is used for trailer towing, driven in a dusty area
or used
off paved roads. Use the Short Trip/City
schedule for these conditions.
Driving a vehicle with a fully warmed engine under
highway conditions will cause engine oil
to break
down slower.
Long Trip/Highway Intervals
Every 7,500 Miles (12 500 km): Engine Oil and Filter
Change (or every
12 months, whichever occurs first).
Chassis Lubrication (or
12 months, whichever
occurs first). Drive Axle Fluid Check. Tire Rotation.
Every 15,000 Miles (25 000 km): Automatic
Transmission Service (severe conditions only).
Every 30,000 Miles (50 000 km): Fuel Filter
Replacement. Engine Air Cleaner Filter Replacement.
Front Wheel Bearing Repack (two-wheel drive only)
(or at each brake relining, whichever occurs first).
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (normal conditions).
Transfer Case Fluid Change.
Every 100,000 Miles (166 000 km): Spark Plug Wire
Inspection. Spark Plug Replacement. Positive
Crankcase Ventilation (PCV) Valve Inspection.
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.
6-6

21,000 Miles (35 000 km) 7,000 Miles (45 000 km)
B Change engine oil and filter (or every 3 months, 0 Change engine oil and filter (or every 3 months,
d Lubricate chassis components (or every 3 months, U Lubricate chassis components (or every 3 months,
whichever
occurs first).
An Emission Control Service. whichever occurs first). An Emission Control Service.
whichever occurs first). (See footnote #.) whichever occurs first). (See footnote #.) ,I
U Check readfront axle fluid level and add fluid as B Check readfront axle fluid level and add fluid as
needed. Check constant velocity joints and axle seals
for leaking.
needed. Check constant
velocity joints and axle seals
for leaking.
30,000 Miles (50 000 km)
24,000 Miles (40 000 km) 0 Change enqine oil and filter (or every 3 months,
u
Change engine oil and filter (or every 3 months,
whichever &curs first). An Emission- Control Service.
Lubricate chassis components (or every 3 months, whichever
occurs first). (See footnote #.)
whichever OCCUrS first). An Emission Control Service. 0 Lubricate chassis components (or every 3 months,
whichever occurs first):
(See footnote #.)
Check readfront axle fluid level and add fluid as
needed. Check constant velocity joints and axle seals
for leaking.
Rotate tires. See
Tire Inspection and Rotation on
page 5-64 for proper rotation pattern and additional
information.
(See footnote +.)
0 Check readfront axle fluid level and add fluid as
needed. Check constant velocity joints and axle seals
for leaking.
0 For Two-Wheel-Drive vehicles only: Clean and repack
the front wheel bearings (or at each brake relining,
whichever occurs first).
(See footnote t.)
0 Replace fuel filter. An Emission Control Service.
B Replace engine air cleaner filter. An Emission Control
Service.
6-9