2000 CHEVROLET EXPRESS automatic transmission

6-19
Automatic Transmission Fluid
If your vehicle has a diesel engine, see ªAutomatic
Transmission Fluidº in the Diesel Supplement.
When to Check and Change
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change both the fluid and filter every 50,000 miles
(83 000 km) if the vehicle's GVWR is over 8,600 or
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 your vehicle's GVWR is not over 8,600 and you do not
use your vehicle under any of these conditions, change the
fluid and filter every 100,000 miles (166 000 km).
See ªScheduled Maintenance Servicesº in the Index.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
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.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:

When outside temperatures are above 90F (32C).

At high speed for quite a while.

In heavy traffic
-- especially in hot weather.

While pulling a trailer.

6-22 How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission fluid to use. See ªRecommended
Fluids and Lubricantsº in the Index.
Add fluid only after checking the transmission fluid
while it is hot. (A cold check is used only as a
reference.) If the fluid level is low, add only enough of
the proper fluid to bring the level up to the HOT area for
a hot check. It doesn't take much fluid, generally less
than one pint (0.5 L). Don't overfill.NOTICE:
We recommend you use only fluid labeled
DEXRON-III, because fluid with that label is
made especially for your automatic transmission.
Damage caused by fluid other than DEXRON
-III
is not covered by your new vehicle warranty.

After adding fluid, recheck the fluid level as
described under ªHow to Check.º

When the correct fluid level is obtained, push the
dipstick back in all the way; then flip the handle
down to lock the dipstick in place.

6-65
POSITION NAME CIRCUITS PROTECTED
14. ILLUM Instrument Panel Cluster, HVAC Controls, RR HVAC Controls,
Instrument Panel Switches, Radio Illumination,
Door Switch Illumination
15. DRL Daytime Running Lamp Relay
16. TURN B/U
Front Turn, RR Turn, Back
-up Lamps, BTSI Solenoid
17.
RADIO
-1Radio (Ign, Accy), Upfitter Provision Relay
18. BRAKE 4WAL PCM, ABS, Cruise Control
19.
RADIO
-BRadio (Battery), Power Antenna
20. TRANS PRNDL, Automatic Transmission
21. SECURITY Passlock
22. RR DEFOG Rear Window Defog
23. NOT USED Not Used
24. RR HVAC RR HVAC Controls, HIGH, MED, LOW Relays
A. PWR ACCY
Power Door Lock, Six
-Way Power Seat, Keyless Entry
Illumination Module
B. PWR WDO Power Windows

Scheduled Maintenance
7-6
Short Trip/City Intervals
Every 24,000 Miles (40 000 km): Diesel Engine Only:
Fuel Cap Replacement, if driving in dusty conditions.
Every 30,000 Miles (50 000 km): Diesel Engine
Only: Engine Air Cleaner Filter Replacement.
Fuel Filter Replacement.
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (vehicles over 8600 GVWR
or driven under severe conditions or equipped with
diesel engine).
Every 60,000 Miles (100 000 km): Engine Accessory
Drive Belt Inspection. If Equipped: Exhaust Gas
Recirculation System Inspection. Gasoline Engine
Only: Evaporative Control System Inspection. Diesel
Engine Only: Crankcase Depression Regulator Valve
(CDRV) System Check.
Short Trip/City Intervals
Every 100,000 Miles (166 000 km): Gasoline Engine
Only: Spark Plug Wire Inspection. Gasoline Engine
Only: Spark Plug Replacement. Gasoline Engine
Only: Automatic Transmission Service (normal
conditions). Gasoline Engine Only (Except 8.1L V8):
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.

Scheduled Maintenance
7-8
Long Trip/Highway Intervals
Every 30,000 Miles (50 000 km): Fuel Filter
Replacement. Diesel Engine Only: Engine Air
Cleaner Filter Replacement. Front Wheel Bearing
Repack (or at each brake relining, whichever
occurs first).
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (vehicles over 8600 GVWR
or driven under severe conditions or equipped with
diesel engine).
Every 60,000 Miles (100 000 km): Engine Accessory
Drive Belt Inspection. If Equipped: Exhaust Gas
Recirculation System Inspection. Gasoline Engine
Only: Evaporative Control System Inspection. Diesel
Engine Only: Crankcase Depression Regulator Valve
(CDRV) System Check.
Long Trip/Highway Intervals
Every 100,000 Miles (166 000 km): Gasoline Engine
Only: Spark Plug Wire Inspection. Gasoline Engine
Only: Spark Plug Replacement. Gasoline Engine
Only: Automatic Transmission Service (normal
conditions). Gasoline Engine Only (Except 8.1L V8):
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
7-20
48,000 Miles (80 000 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 #.)

Check axle fluid level and add fluid as needed.

Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)

Diesel Engine Only: Replace fuel cap if driving in dusty conditions.
An Emission Control Service.
50,000 Miles (83 000 km)

Change automatic transmission fluid and filter if the vehicle has a diesel
engine, if the vehicle's GVWR is over 8600 lbs. or if the vehicle is mainly
driven under one or more of these conditions:
± In heavy city traffic where the outside temperature regularly
reaches 90
F (32
C) 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 at 100,000 miles (166 000 km).
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE

Short Trip/City Scheduled Maintenance
7-32
100,000 Miles (166 000 km)

Gasoline Engine Only: Inspect spark plug wires. An Emission Control Service.

Gasoline Engine Only: Replace spark plugs. An Emission Control Service.

Change automatic transmission fluid and filter if the vehicle has a diesel
engine, if the vehicle's GVWR is over 8600 lbs. or if the vehicle is mainly
driven under one or more of these conditions:
± In heavy city traffic where the outside temperature regularly
reaches 90
F (32
C) or higher.
± In hilly or mountainous terrain.
± When doing frequent trailer towing.
± Uses such as found in taxi, police or delivery service.
If you haven't used your vehicle under severe service conditions listed
previously and, therefore, haven't changed your automatic transmission fluid,
change both the fluid and filter.
Gasoline Engine Only (Except 8.1L V8): Inspect Positive Crankcase
Ventilation (PCV) valve. An Emission Control Service.
150,000 Miles (240 000 km)
Drain, flush and refill cooling system (or every 60 months since last service,
whichever occurs first). See ªEngine Coolantº in the Index for what to use.
Inspect hoses. Clean radiator, condenser, pressure cap and neck. Pressure test
cooling system and pressure cap. An Emission Control Service.
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE

Long Trip/Highway Scheduled Maintenance
7-39
50,000 Miles (83 000 km)

Change automatic transmission fluid and filter if the vehicle has a diesel
engine, if the vehicle's GVWR is over 8600 lbs. or if the vehicle is mainly
driven under one or more of these conditions:
± In heavy city traffic where the outside temperature regularly
reaches 90
F (32
C) 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 at 100,000 miles (166 000 km).
52,500 Miles (87 500 km)
Change engine oil and filter (or every 12 months, whichever occurs first).
An Emission Control Service.
Lubricate chassis components (or every 12 months, whichever occurs first).
(See footnote #.)
Check axle fluid level and add fluid as needed.
Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE