Page 370 of 468

6-28 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.
Manual Transmission Fluid
When to Check
A good time to have it checked is when the engine oil
is changed. See your maintenance schedule to find out
when to change your transmission fluid.
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.
Be sure to get an accurate reading if you check
your transmission fluid.
Page 420 of 468

6-78
Name Usage
ETC Electronic Throttle Control
IGN E A/C Compressor Relay, Rear
Window Defogger, Daytime
Running Lamps, A.I.R. System
B/U LP Backup Lamps, Automatic
Transmission Shift Lock
Control System
ATC Automatic Transfer Case
RR DEFOG Rear Window Defogger,
Heated Mirrors (Relay)
RR PRK Right Rear Parking Lamps
ECM B PCM
F/PMP Fuel Pump (Relay)
O2 A Oxygen Sensors
FUEL HT Fuel Heater, Glow Plug and
Intake Heater Controls
O2 B Oxygen Sensors
LR PRK Left Rear Parking Lamps
RR DEFOG Rear Window Defogger,
Heated MirrorsName Usage
HDLP Headlamps (Relay)
TRL PRK Parking Lamps Trailer Wiring
RT HDLP Right Headlamps
DRL Daytime Running Lamps (Relay)
HTD MIR Heated Mirrors
LT HDLP Left Headlamps
A/C Air Conditioning
AUX PWR Cigarette Lighter, Auxiliary
Power Outlets
SEO 2 Special Equipment Option Power,
Power Seats, Aux Roof Mnt Lamp
SEO 1 Special Equipment Option Power, Aux
Roof Mnt Lamp, Cell Phone, OnStar
DRL Daytime Running Lamps
A/C A/C (Relay)
FOG LP Fog Lamps
FOG LP Fog Lamps (Relay)
RADIO Audio System, Instrument Cluster,
Climate Control System
Page 421 of 468
6-79
Name Usage
CIGAR Cigarette Lighter,
Auxiliary Power Outlets
RT TURN Right Turn Signals
BTSI Automatic Transmission Shift
Lock Control System
LT TURN Left Turn Signals
FR PRK Front Parking Lamps,
Sidemarker Lamps
W/W PMP Windshield Washer Pump
HORN Horn (Relay)
IGN C Ignition Switch, Fuel Pump,
PRND321 Display, Crank
RDO AMP Not Used
HAZ LP Exterior Lamps, Hazard Lamps
EXP LPS Not Used
HORN Horn
CTSY LP Interior Lamps
RR WPR Not Used
TBC Body Control Module, Remote
Keyless Entry, HeadlampsReplacement Bulbs
Low-Beam Headlamps2 9006
High
-Beam Headlamps2 9005
Daytime Running Lamps (DRL) 2 3157KX
Front Marker Lamp 2 194
Front Parking and Turn Lamp 2 3157 A
Rear Marker Lamp,
Taillamp and Stop Lamp2 3157
Taillamp and Stop Lamp** 2 1157
Rear Turn Lamp 2 3157
Rear Turn Lamp ** 2 1156
Back
-up Lamp2 3157
Back
-up Lamp **2 1156
Center High
-Mounted Stoplamp2 912
Cargo Lamp 2 912
* For replacement bulbs not listed here, please consult
your dealer.
** Chassis Cab Models
Page 423 of 468
6-81 Cooling System Capacity
After refill, the level must be rechecked. See ªCooling Systemº in the Index.
Engine Transmission Quantity
VORTEC 4300 V6 Automatic 12.6 quarts (11.9 L)
VORTEC 4300 V6 Manual 12.9 quarts (12.2 L)
VORTEC 4800 V8 Automatic 13.4 quarts (12.7 L)
VORTEC 4800 V8 Manual 13.7 quarts (13.0 L)
VORTEC 5300 V8 Automatic 13.4 quarts (12.7 L)
VORTEC 5300 V8** Automatic 14.9 quarts (14.1 L)
VORTEC 6000 V8 Automatic 14.8 quarts (14.0 L)
VORTEC 6000 V8* Automatic 14.4 quarts (13.6 L)
VORTEC 6000 V8 Manual 15.2 quarts (14.4 L)
VORTEC 6000 V8* Manual 14.8 quarts (14.0 L)
VORTEC 6600 V8 Manual 20.7 quarts (19.6 L)
VORTEC 6600 V8 Automatic 20.3 quarts (19.2 L)
VORTEC 8100 V8 Manual 21.1 quarts (20.0 L)
VORTEC 8100 V8 Automatic 20.7 quarts (19.6 L)
* Vehicles equipped with the optional engine oil cooler.
** Vehicles equipped with the optional air conditioner.
Page 435 of 468
Scheduled Maintenance -- Gasoline Engines
7-10
22,500 Miles (37 500 km)
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.
Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
25,000 Miles (41 500 km)
Allison Transmission Only: Change automatic transmission fluid and filters
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
ACTUAL
SERVICED BY:MILEAGE
DATE
Page 437 of 468

Scheduled Maintenance -- Gasoline Engines
7-12
50,000 Miles (83 000 km)
Except Allison Transmission: Change automatic transmission fluid and filter
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
90F (32C) or higher.
± In hilly or mountainous terrain.
± When doing frequent trailer towing.
± Uses such as found in taxi, police or delivery service.
Except Allison Transmission: If you do not use your vehicle under any of
these conditions, change the fluid and filter at 100,000 miles (166 000 km).
Allison Transmission Only: If you haven't used your vehicle under severe
conditions listed previously and, therefore, haven't changed your automatic
transmission fluid, change both the fluid and filter.
Automatic Transfer Case Only: Change transfer case fluid.
52,500 Miles (87 500 km)
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.
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
Page 439 of 468

Scheduled Maintenance -- Gasoline Engines
7-14
67,500 Miles (112 500 km)
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.
Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
75,000 Miles (125 000 km)
If Equipped: Replace passenger compartment air filter. If you drive regularly
under dusty conditions, the filter may require replacement more often.
Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking.
Allison Transmission Only: 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).
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
Page 441 of 468
Scheduled Maintenance -- Gasoline Engines
7-16
100,000 Miles (166 000 km)
Inspect spark plug wires.
An Emission Control Service.
Replace spark plugs.
An Emission Control Service.
Change automatic transmission fluid and filter 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
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 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.
Automatic Transfer Case Only: Change transfer case fluid.
Inspect Positive Crankcase Ventilation (PCV) valve.
An Emission Control Service. ACTUAL
SERVICED BY:MILEAGE
DATE