2002 GMC SONOMA transmission

6-23
Manual Transmission Fluid
When to Check
A good time to have it checked is when the engine oil is
changed. However, the fluid in your manual
transmission doesn't require changing.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at your GM dealership service
department.
If you do it yourself, be sure to follow all the
instructions here, or you could get a false reading.
NOTICE:
Too much or too little fluid can damage your
transmission. Too much can mean that some of
the fluid could come out and fall on hot engine
parts or exhaust system parts, starting a fire. Too
little fluid could cause the transmission to
overheat. Be sure to get an accurate reading if
you check your transmission fluid.
Check the fluid level only when your engine is off, the
vehicle is parked on a level place and the transmission is
cool enough for you to rest your fingers on the
transmission case.
Then, follow these steps:
1. Remove the filler plug.
2. Check that the lubricant level is up to the bottom of
the filler plug hole.
3. If the fluid level is good, install the plug and be sure
it is fully seated. If the fluid level is low, add more
fluid as described in the next steps.

6-69
Fuse/Circuit
BreakerUsage
14 Power Locks
15 4WD Switch, Engine Control
(VCM, PCM, Transmission)
16 Supplemental Inflatable Restraint
17 Front Wiper
18 Steering Wheel, Radio, Ignition
19 Radio Battery
20 Amplifier
21 HVAC I, HVAC Control Head,
HVAC Devices
22 Anti
-Lock Brakes
23 Rear Wiper
24 Radio, Ignition
Engine Compartment Fuse Block
The fuse block is located under the hood on the driver's
side of the engine compartment. See ªEngine
Compartment Overviewº in the Index for more
information on location.
Remove the cover by turning the fastener
counterclockwise. To reinstall the fuse panel cover,
push in and turn the fastener clockwise.

6-70
Name Usage
TRL TRN Not Used
TRR TRN Not Used
TRL B/U Not Used
VEH B/U Vehicle Back
-Up Lamps
RT TURN Right Turn Signal FrontName Usage
LT TURN Left Turn Signal Front
HDLP W/W Not Used
LT TRN Left Turn Signal Rear
RT TRN Right Turn Signal Rear
RR PRK Right Rear Parking Lamps
TRL PRK Not Used
LT HDLP Left Headlamp
RT HDLP Right Headlamp
FR PRK Front Parking Lamps
INT BAT I/P Fuse Block Feed
ENG I Engine Sensors/Solenoids, MAF,
CAM, PURGE, VENT
ECM B Engine Control Module, Fuel
Pump Module, Oil Pressure
ABS Anti
-Lock Brake System
ECM I Engine Control Module Injectors
BTSI Automatic Transmission Shift
Lock Control System

6-73
Automatic Transmission
Drain and Refill 5.0 quarts (4.7 L). . . . . . . . . . . . . .
Differential Fluid
Rear Axle 4.0 pints (1.9 L). . . . . . . . . . . . . . . . . . .
Front Axle 2.6 pints (1.2 L). . . . . . . . . . . . . . . . . . .
All capacities are approximate. After refill, the level
must be checked.
All capacities are approximate. When adding, be sure to
fill to the appropriate level or as recommended in this
manual. See ªRecommended Fluids and Lubricantsº in
the Index.
ªVORTECº 2200 L4 (VIN Code 5)
Engine Specifications
Type L4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Firing Order 1
-3-4-2 . . . . . . . . . . . . . . . . . . . . . . . . . .
Spark Plug Gap 0.040 inches (1.01 mm). . . . . . . . . .
ªVORTECº 4300 V6 (VIN Code W)
Engine Specifications
Type V6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Firing Order 1
-6-5-4-3-2 . . . . . . . . . . . . . . . . . . . . . .
Spark Plug Gap 0.060 inches (1.52 mm). . . . . . . . . .
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 R134a 1.8 lbs (.79 kg). . . . . . . . . . . .
Use Refrigerant Oil, R134a Systems

6-74
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 dealer.
ªVORTECº 2200 L4 (VIN Code 5)
Engine Specifications
Oil Filter *PF47. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Cleaner Filter *A1163C. . . . . . . . . . . . . . . . . . . . .
PCV Valve N/A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Automatic Transmission Filter Kit **24200796. . . .
Spark Plugs *41
-948 . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Filter *GF481. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Windshield Wiper
Blades (Trico) 20 inches (51 cm). . . . . . . . . . . . . . .
*ACDelco

Part No.
**GM Part No.
ªVORTECº 4300 V6 (VIN Code W)
Engine Specifications
Oil Filter *PF47. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Cleaner Filter *A1163C. . . . . . . . . . . . . . . . . . . . .
PCV Valve *CV769C. . . . . . . . . . . . . . . . . . . . . . . . .
Automatic Transmission Filter Kit **24200796. . . .
Spark Plugs *41
-948 . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Filter *GF481. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Windshield Wiper
Blades (Trico) Trico 20 inches (51 cm). . . . . . . . . .
*ACDelco

Part No.
**GM Part No.

Scheduled Maintenance
7-5
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).

Your vehicle has the 2200 L4 (Code 5) flexible
fuel engine and you have used ethanol fuel
(85% Ethanol/E
-85).

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 occurs first). Chassis
Lubrication (or 3 months, whichever occurs first).
Drive Axle Service.
Every 6,000 Miles (10 000 km): Tire Rotation.
Every 15,000 Miles (25 000 km): Engine Air Cleaner
Filter Inspection, if driving in dusty conditions. Front
Wheel Bearing Repack (2WD 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
(4.3L V6 engine only).
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (normal conditions).
Every 60,000 Miles (100 000 km): Engine Accessory
Drive Belt Inspection.
(Continued)

Scheduled Maintenance
7-7
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 every 12 months, whichever
occurs first). Drive Axle Service. 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 (4.3L V6 engine only). Engine Air
Cleaner Filter Replacement. Front Wheel Bearing
Repack (2WD only) (or at each brake relining,
whichever occurs first).
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (normal conditions).
Long Trip/Highway Intervals
Every 60,000 Miles (100 000 km): Engine Accessory
Drive Belt Inspection.
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).
These intervals only summarize maintenance services.
Be sure to follow the complete scheduled maintenance
on the following pages.

Short Trip/City Scheduled Maintenance
7-11
15,000 Miles (25 000 km)

Change engine oil and filter (or every 3 months, whichever occurs first).
An Emission Control Service.

Lubricate chassis components (or every 3 months, whichever occurs first).
(See footnote #.)

Inspect engine air cleaner filter if you are driving in dusty conditions.
Replace filter if necessary.
An Emission Control Service. (See footnote
.)
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)
For Two
-Wheel-Drive vehicles only: Clean and repack the front wheel
bearings (or at each brake relining, whichever occurs first).
Change automatic transmission fluid and filter if the vehicle is mainly driven
under one or more of these conditions:
± In heavy city traffic where the outside temperature regularly
reaches 90F (32C) or higher.
± In hilly or mountainous terrain.
± When doing frequent trailer towing.
± Uses such as found in taxi, police or delivery service.
If you do not use your vehicle under any of these conditions, change the fluid
and filter every 50,000 miles (83 000 km).
ACTUAL
SERVICED BY:MILEAGE
DATE