Page 352 of 394

6-64
Name Usage
STUD #1 Accessory Power/Trailer Wiring
Feed/Load Leveling
ABS Anti
-Lock Brakes
IGN A Ignition Switch
AIR A.I.R. System
RAP #1 Retained Accessory Power, Power
Mirrors, Power Door Locks,
Power Seat(s)
IGN B Ignition Switch
RAP #2 Retained Accessory Power/Rear
Power Windows, Sunroof, Radio
STUD #2 Accessory Power/Trailer Wiring
Brake Feed
TRL R TRN Right Turn Signal Trailer Wiring
TRL L TRN Left Turn Signal Trailer Wiring
IGN 1 Ignition, Fuel Controls
INJ
-B Ignition, Fuel Controls (Relay)
STARTER Starter (Relay)
PARK LP Parking Lamps
FRT HVAC Climate Control System
STOP LP Exterior Lamps, Stoplamps
ECM 1 VCM/PCMName Usage
CHMSL Center High Mounted Stoplamp
VEH STOP Stoplamps, Cruise Control
TRL B/U Backup Lamps Trailer Wiring
INJ
-A Fuel Controls, Ignition
RR HVAC Rear HVAC
VEH B/U Vehicle Backup Lamps
ENG 1 Engine Controls, Canister Purge,
Fuel System
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)
RTD Autoride (Real Time Damping)
RR PRK Right Rear Parking Lamps
ECM B VCM/PCM
F/PMP Fuel Pump (Relay)
Page 354 of 394

6-66
Replacement Bulbs
Bulb Number
Low
-Beam Headlamps 9005 or 9005 (long life). . . .
High
-Beam Headlamps 9005. . . . . . . . . . . . . . . . . . .
Daytime Running Lamps (DRL) 3157KX. . . . . . . . . .
Front Marker Lamp 194. . . . . . . . . . . . . . . . . . . . . . .
Front Parking and
Turn Lamp 3157 or 3157K (long life). . . . . . . . . . . .
Rear Marker Lamp, Taillamp
and Stop Lamp 3157. . . . . . . . . . . . . . . . . . . . . . . .
Rear Turn Lamp 3157. . . . . . . . . . . . . . . . . . . . . . . . .
Back
-up Lamp 3157. . . . . . . . . . . . . . . . . . . . . . . . . .
For replacement bulbs not listed here, please consult
your dealer.
Capacities and Specifications
Please refer to ªRecommended Fluids and Lubricantsº
in the Index for more information. See refrigerant
charge label under the hood for charge capacity
information and requirements.
Engine VORTEC 6000. . . . . . . . . . . . . . . . . . . . . . . .
Type V8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VIN Code U. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Spark Plug Gap 0.060 inches (1.52 mm). . . . . . . . . .
Wheels and Tires
Wheel Nut Torque 140 lb-ft (190 N´m) . . . . . . . . . . .
Tire Pressure See the Certification/Tire label. . . . . . .
on the rear edge of the driver's door or the
incomplete vehicle document in the cab.
Page 355 of 394

6-67 Capacities
*Cooling System 14.8 quarts (14.0 L). . . . . . . . . . . .
*Cooling System with
Engine Oil Cooler 15.4 quarts (14.6 L). . . . . . . . .
Crankcase with Filter 6.0 quarts (5.7 L). . . . . . . . . . .
Fuel Tank
Denali 26.0 U.S. gallons (98.4 L). . . . . . . . . . . . . .
Denali XL 32.5 U.S. gallons (123.0 L). . . . . . . . . .
*Add 1.05 quarts (1 L) if equipped with rear heating.
All capacities are approximate. After refill, the levels
must be rechecked.
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.These specifications are for information only. If you
have any questions, see the service manual for the
chassis or refer to the body manufacturer's publications.
Oil Filter* PF59. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Air Cleaner/Filter* A1518C. . . . . . . . . . . . . . .
Passenger Compartment
Air Filter Kit** 52485513. . . . . . . . . . . . . . . . . . . .
PCV Valve* CV948C. . . . . . . . . . . . . . . . . . . . . . . . .
Spark Plugs PTZ16R15 Denso***. . . . . . . . . . . . . . .
PZTR5A15 NGK***
Fuel Filter* GF626. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wiper Blades (Front)** 15706394. . . . . . . . . . . . . . .
Wiper Blade Type (Front) ITTA. . . . . . . . . . . . . . . . .
Wiper Blade Length (Front) 22.0 inches (56.0 cm). . .
Wiper Blades (Rear)** 22154396. . . . . . . . . . . . . . . .
Wiper Blade Type (Rear) ITTA. . . . . . . . . . . . . . . . . .
Wiper Blade Length (Rear) 18.0 inches (45.0 cm). . .
* ACDelco
Part No.
**GM Part No.
***Spark Plug Gap is 0.060 inches
Page 361 of 394

Scheduled Maintenance
7-6Engine Oil and Chassis Lubrication
Scheduled Maintenance
Change engine oil and filter as indicated by the
GM Oil Life System (or every 12 months,
whichever occurs first). Reset the system. The system
will show you when to change the oil
-- usually between
3,000 miles (5 000 km) and 10,000 miles (16 000 km)
since your last oil change. Under severe conditions, the
indicator may come on before 3,000 miles (5 000 km).
Never drive your vehicle more than 10,000 miles
(16 000 km) or 12 months without an oil and
filter change.The system won't detect dust in the oil. So if you
drive in a dusty area, be sure to change your oil and
filter every 3,000 miles (5 000 km) or sooner if the
CHANGE ENGINE OIL message appears. Remember
to reset the Oil Life System when the oil and filter have
been changed. See ªOil Life Systemº in the Index for
information on resetting.
An Emission Control Service.
Lubricate chassis components with each engine oil and
filter change. Lubricate the front suspension, ball joints,
steering linkage, transmission shift linkage, transfer case
shift linkage, parking brake cable guides, and brake
front axle. Ball joints should not be lubricated unless
their temperature is 10F (
-12C) or higher, or they
could be damaged.
Page 367 of 394
Scheduled Maintenance
7-12
60,000 Miles (100 000 km)
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.
Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
Inspect engine accessory drive belt.
An Emission Control Service.
Replace fuel filter.
An Emission Control Service. (See footnote .)
Inspect Exhaust Gas Recirculation (EGR) system as described in the
service manual.
An Emission Control Service.
(See footnote .)
Inspect Evaporative Control System. Check all fuel and vapor lines and hoses
for proper hook
-up, routing and condition. Check that the purge valve works
properly, if equipped. Replace as needed.
An Emission Control Service. (See footnote .)
ACTUAL
SERVICED BY:MILEAGE
DATE
Page 370 of 394

Scheduled Maintenance
7-15
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 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.
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
the cooling system and pressure cap.
An Emission Control Service.ACTUAL
SERVICED BY:MILEAGE
DATE
Page 371 of 394

7-16
Part B: Owner Checks and Services
Listed in this part are owner checks and services which
should be performed at the intervals specified to help
ensure the safety, dependability and emission control
performance of your vehicle.
Be sure any necessary repairs are completed at once.
Whenever any fluids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
in Part D.
At Each Fuel Fill
It is important for you or a service station attendant
to perform these underhood checks at each fuel fill.
Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. See ªEngine Oilº in the Index for
further details.Engine Coolant Level Check
Check the engine coolant level and add DEX
-COOL
coolant mixture if necessary. See ªEngine Coolantº in
the Index for further details.
Windshield Washer Fluid Level Check
Check the windshield washer fluid level in the
windshield washer tank and add the proper fluid if
necessary. See ªWindshield Washer Fluidº in the
Index for further details.
At Least Once a Month
Tire Inflation Check
Make sure tires are inflated to the correct pressures.
Don't forget to check your spare tire. See ªTiresº
in the Index for further details.
Cassette Deck Service
Clean cassette deck. Cleaning should be done every
50 hours of tape play. See ªAudio Systemsº in the
Index for further details.
Page 372 of 394

7-17 At Least Twice a Year
Restraint System Check
Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors and anchorages are
working properly. Look for any other loose or damaged
safety belt system parts. If you see anything that might
keep a safety belt system from doing its job, have it
repaired. Have any torn or frayed safety belts replaced.
Also look for any opened or broken air bag coverings,
and have them repaired or replaced. (The air bag system
does not need regular maintenance.)
Wiper Blade Check
Inspect wiper blades for wear or cracking. Replace blade
inserts that appear worn or damaged or that streak or
miss areas of the windshield. Also see ªWiper Blades,
Cleaningº in the Index.Spare Tire Check
At least twice a year, after the monthly inflation check
of the spare tire determines that the spare is inflated to
the correct tire inflation pressure, make sure that the
spare tire is stored securely. Push, pull, and then try
to rotate or turn the tire. If it moves, use the wheel
wrench/ratchet to tighten the cable. See ªStoring the
Spare Tire and Toolsº in the Index.
Engine Air Cleaner Filter Restriction
Indicator Check
Your vehicle has an indicator located on the air cleaner
in the engine compartment that lets you know when the
air cleaner filter is dirty and needs to be changed. Check
indicator at least twice a year or when your engine oil is
changed, whichever occurs first. See ªAir Cleanerº in
the Index for more information. Inspect your air cleaner
filter restriction indicator more often if the vehicle is
used in dusty areas or under off road conditions.