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Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside of
Your Vehicle..............................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Specifications....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-5
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-6
Filling a Portable Fuel Container.......................5-8
Checking Things Under
the Hood......................................................5-8
Hood Release................................................5-9
Engine Compartment Overview.......................5-10
Engine Oil...................................................5-13
Engine Air Cleaner/Filter................................5-18
Automatic Transmission Fluid
.........................5-20
Manual Transmission Fluid
.............................5-23
Hydraulic Clutch
...........................................5-24Engine Coolant.............................................5-25
Radiator Pressure Cap..................................5-27
Engine Overheating.......................................5-28
Cooling System............................................5-30
Engine Fan Noise.........................................5-36
Power Steering Fluid.....................................5-37
Windshield Washer Fluid................................5-38
Brakes........................................................5-39
Battery........................................................5-42
Jump Starting...............................................5-43
Rear Axle.......................................................5-47
Four-Wheel Drive............................................5-48
Front Axle......................................................5-49
Bulb Replacement..........................................5-50
Halogen Bulbs..............................................5-50
Headlamps..................................................5-50
One-Piece Front Turn Signal Lamps................5-52
Two-Piece Front Turn Signal Lamps................5-53
Center High-Mounted Stoplamp (CHMSL).........5-54
Taillamps.....................................................5-55
Replacement Bulbs.......................................5-55
Section 5 Service and Appearance Care
5-1
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A. Battery
B. Coolant Recovery Tank
C. Automatic Transmission Dipstick (If Equipped)
D. Engine Oil Fill Cap and Dipstick
E. Power Steering ReservoirF. Brake Master Cylinder
G. Engine Air Cleaner/Filter
H. Engine Compartment Fuse Block
I. Windshield Washer Fluid Reservoir
5-11
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When you open the hood on the 4300 V6 engine, you’ll see:
A. Battery
B. Coolant Recovery Tank
C. Engine Oil Dipstick
D. Engine Oil Fill
E. Automatic Transmission Dipstick (If Equipped)F. Power Steering Reservoir
G. Brake Master Cylinder Reservoir
H. Engine Air Cleaner/Filter
I. Engine Compartment Fuse Block
J. Windshield Washer Fluid Reservoir
5-12
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Engine Air Cleaner/Filter
SeeEngine Compartment Overview on page 5-10for
more information on the location of the engine air
cleaner/filter.
2200 L4 Engine
4300 V6 Engine
5-18
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When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/filter every 15,000 miles
(25 000 km) and replace every 30,000 miles (50 000 km).
If you are driving in dusty/dirty conditions, inspect the
filter at each engine oil change.
How to Inspect the Engine Air
Cleaner/Filter
To remove either engine air cleaner/filter, do the
following:
1. Remove the fasteners that hold the cover on and
remove the cover
2. Lift out the engine air cleaner/filter, if needed.
3. Insert a new airfilter. SeeNormal Maintenance
Replacement Parts on page 5-96to determine
whichfilter to use.
4. Reinstall the engine air cleaner/filter cover.
Tighten the fasteners to hold the cover in place.
{CAUTION:
Operating the engine with the air cleaner/ lter
off can cause you or others to be burned. The
air cleaner not only cleans the air, it helps to
stop ame if the engine back res. If it isn’t there
and the engine back res, you could be burned.
Don’t drive with it off, and be careful working on
the engine with the air cleaner/ lter off.
Notice:If the air cleaner/ lter is off, a back re can
cause a damaging engine re. And, dirt can
easily get into your engine, which will damage it.
Always have the air cleaner/ lter in place when
you’re driving.
5-19
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Normal Maintenance Replacement Parts
Part Number
Oil Filter*PF47
Air Cleaner Filter*A1163C
PCV Valve
2200 Engine
4300 EngineN/A
*CV7696
Automatic Transmission Filter Kit **24200796
Spark Plugs*41-948
Fuel Filter*GF481
Windshield Wiper Blades
Length
Type20 inches (51 cm)
Trico
*ACDelco
®Part No.
**GM Part No.
5-96
2003 - Sonoma OM
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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:
•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.
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 occursfirst). Chassis
Lubrication (or 3 months, whichever occursfirst).
Drive Axle Service.
Every 6,000 Miles (10 000 km):Tire Rotation.
Every 15,000 Miles (25 000 km):Engine Air Cleaner
Filter Inspection. Front Wheel Bearing Repack
(two-wheel drive only) (or at each brake relining,
whichever occursfirst). Automatic Transmission Service
(severe conditions only).
Every 30,000 Miles (50 000 km):Engine Air
Cleaner Filter Replacement. Fuel Filter Replacement
(4.3L V6 engine only).
Every 50,000 Miles (83 000 km):Automatic
Transmission Service (normal conditions).
Every 90,000 Miles (150 000 km):Fuel Filter
Replacement (2200 L4 engine only).
Every 100,000 Miles (166 000 km):Spark Plug Wire
Inspection. Spark Plug Replacement. 4.3L V6 Engine
Only: Positive Crankcase Ventilation (PCV) Valve
Inspection.
6-5
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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.
Long Trip/Highway Definition
Follow this scheduled maintenanceonlyif 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
occursfirst). Drive Axle Service. Tire Rotation.
Every 15,000 Miles (25 000 km):Engine Air Cleaner
Filter Inspection. Automatic Transmission Service
(severe conditions only).Every 30,000 Miles (50 000 km):Fuel Filter
Replacement (4.3L V6 engine only). Engine Air Cleaner
Filter Replacement. Front Wheel Bearing Repack
(two-wheel drive only) (or at each brake relining,
whichever occursfirst).
Every 50,000 Miles (83 000 km):Automatic
Transmission Service (normal conditions).
Every 90,000 Miles (150 000 km):Fuel Filter
Replacement (2200 L4 engine only).
Every 100,000 Miles (166 000 km):Spark Plug Wire
Inspection. Spark Plug Replacement. 4.3L V6 Engine
Only: 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
2003 - Sonoma OM