2003 GMC YUKON DENALI automatic transmission

37,500 Miles (62 500 km)
U Check readfront axle fluid level and add fluid as
needed. Check constant velocity joints and axle seals
for leaking.
page 5-56 for proper rotation pattern and additional
information. (See footnote
+.)
U Rotate tires. See Tire inspection and Rotation on
45,000 Miles (75 000 km)
D Check readfront axle fluid level and add fluid as
needed. Check constant velocity joints and axle seals
for leaking.
page 5-56 for proper rotation pattern and additional
information. (See footnote
+.)
U Rotate tires. See Tire Inspection and Rotation on
50,000 Miles (83 000 km)
0 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
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 Milles (87 500 km)
U Check readfront axle fluid level and add fluid as
needed. Check constant velocity joints and axle seals
for leaking.
page 5-56 for proper rotation pattern and additional
information. (See footnote
+.)
D Rotate tires. See Tire lnspection and Rotation on
60,000 Miles (100 000 km)
U Check readfront axle fluid level and add fluid as
needed. Check constant velocity joints and axle seals
for leaking.
page 5-56 for proper rotation pattern and additional
information. (See footnote
+.)
Ll Replace fuel filter. An Emission Control Service.
(See footnote
t.)
lJ 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
t.)
U Rotate tires. See Tire lnspection and Rotation on
6-i

100,000 Miles (166 000 km)
0 Inspect spark plug wires. An Emission Control
ii Repiace spark piugs. An Emission Zoniroi Service.
0 Change automatic transmission fluid and filter if
the vehicle is mainly driven under one or more
of these conditions:
Service.
- 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.
Ll 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.
150,000 Miles (240 000 km)
0 Drain, flush and refill cooling system (or every
60 months since last service, whichever occurs first). See
Engine Codant on page 5-22 for what to me.
Inspect hoses. Clean radiator, condenser, pressure
cap and neck. Pressure test the cooling system
and pressure cap. An Emission Control Service.
0 Inspect engine accessory drive belt. An Emission
Control Service.
U Inspect Positive Crankcase Ventilation (PCV) valve.
An Emission Control Service.
6-9

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.)
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
Cleaning the Outside
of Your Vehicle on page 5-81.
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
wrenchhatchet
to tighten the cable. See Changing a Flat
Tire
on page 5-63.
Engine Air Cleaner Filter Restriction
Indicator Check
Your vehicle has an engine air cleaner filter restriction
indicator located on the air cleaner in the engine
compartment. The indicator lets you know when the air
cleaner filter is dirty and needs
to be changed. Check
the indicator at least twice a year or when your engine oil is changed,
whichever occurs first. See Engine Air
Cleaner/Filter
on page 5- 17 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.
Weatherstrip Lubrication
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth. During very cold,
damp weather more frequent application may be required. See
Part D: Recommended Fluids and
Lubricants
on page 6- 15.
Automatic Transmission Check
Check the transmission fluid level; add if needed. See
Automatic Transmission Fluid on page
5-20. A fluid loss
may indicate a problem. Check the system and repair
if needed.
At Least Once a Year
Key Lock Cylinders Service
Lubricate the key lock cylinders with the lubricant
specified in Part D.

Body Lubrication Service
Lubricate all hood latch assembly, secondary latch,
pivots, spring anchor, release pawl, door hinges, liftgate
hinge, liftgate linkage, liftgate handle pivot points, latch
bolt, fuel door hinge, locks and folding seat hardware.
Part
D tells you what to use. More frequent lubrication
may be required when exposed
to a corrosive
environment.
Star+nr Sw'+zh Check
ten you are doing this check, the v_--icle
could move suddenly.
If it does, you or others
could be injured. Follow the steps below.
3. Try to start the engine in each gear. The starter
should work only in PARK (P) or NEUTRAL (N).
If the starter works in any other position, your
vehicle needs service.
Automatic Transmission Shift Lock
Control System Check
1. Before you start, be sure you have enough room
2. Firmly apply both the parking brake and the regular
around
the vehicle.
brake. See Parking Brake on page
2-25 if
necessary.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
Whe.. IOU a1 - rloing this check, tt.- vehicle
could move suddenly.
If it does, you or others
could
be injured. Follow the steps below.
1. Before you start, be sure you have enough room
around the vehicle.
It should be parked on a level
surface.
2. Firmly apply the parking brake. See Parking Brake
on page 2-25 if necessary.
Be ready
to apply the regular brake immediately if
the vehicle begins to move.
3. With the engine off, turn the key to the RUN
position, but don't start the engine. Without applying
the regular brake, try to move the shift lever
out
of PARK (P) with normal effort. If the shift lever
moves out of PARK
(P), your vehicle needs service.
6-1 2

Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn
the ignition key
to LOCK in each shift lever position.
0 The key should turn to LOCK only when the
The key should come out only in LOCK.
shift
lever is in PARK (P).
Parking Brake and Automatic
Transmission Park
(P) Mechanism
Check
WI..,.J you are doin, ,his cl.,:k, your --hide
could begin to move. You or others could be
injured and property could be damaged. Make
sure there is room in front
of your vehicle in
case it begins to roll. Be ready to apply the
regular brake at once should the vehicle begin
to move.
Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular brake, set the
parking brake.
To check the parking brake’s holding ability: With
the engine running and transmission in NEUTRAL
(N), slowly remove foot pressure from the regular
brake pedal. Do this until the vehicle is held by the
parking brake only.
0 To check the PARK (P) mechanism’s holding
ability: With the engine running, shift to PARK (P).
Then release the parking brake followed by the
regular brake.
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
6-1 3

Part D: Recommended Fluids and
Lubricants
Flyids and lubricants identified below by mme,
part number or specification may be obtained from
your dealer.
Usage
Engine Oil
Engine Coolant
Hydraulic Brake
System
Windshield
Washer Solvent
Fluid/Lubricant
Engine oil with the American
Petroleum Institute Certified for
Gasoline Engines starburst symbol
of the proper viscosity. To determine
the preferred viscosity for your
vehicle's engine, see Engine
Oil on
page
5- 13.
50/50 mixture of clean, drinkable
water and use only
DEX-COOL@Coolant. See Engine
Coolant on page
5-22.
Delco Supreme 1 l@ Brake Fluid or
equivalent
DOT-3 brake fluid.
GM Optikleen@Washer Solvent or
equivalent.
Usage
Power Steering System
Automatic
Transmission
Key Lock
Cylinders
Chassis
Lubrication
Front and
Rear Axle
Transfer Case
Fluid/Lubricant
GM Power Steering Fluid (GM Part No.
U.S. 1052884, in Canada
993294, or equivalent).
DEXRON@-Ill Automatic
Transmission Fluid.
Mulit-Purpose Lubricant, Superlube
(GM Part No.
U.S. 12346241 , in
Canada 10953474, or equivalent).
Chassis Lubricant (GM Part No.
U.S. 12377985, in Canada
88901242, or equivalent) or lubricant
meeting requirements of NLGl
#2,
Category LB or GC-LB.
SAE 75W-90 Synthetic Axle Lubricant (GM Part
No. U.S.
12378261, in Canada 10953455) or
equivalent meeting GM Specification
99861
15.
DEXRON@-Ill Automatic
Transmission Fluid.
6-1 5

Automatic Headlamp System ............................ 3-1 4
Automatic Level Control
................................... 4-46
Automatic Transmission Fluid
.......................................................... 5-20
Operation
................................................... 2-22
Automatic Transmission Check
.......................... 6-1 1
Automatic Transmission Shift Lock Control
System Check
............................................. 6-12
AutorideTM
................................................. 4-46
B
Backing Up .................................................... 4-54
Battery
.......................................................... 5-39
Battery Replacement
......................................... 2-6
Battery Run-Down Protection
............................ 3-1 7
Before You Drive
............................................ 3-72
Bench Seat
.................................................... 1-17
Bench Seat Split (50/50)
.................................. 1-1 1
Bench Seat, Split (60/40)
................................... 1-9
Body Lubrication Service
.................................. 6-12
Brake
Parking
...................................................... 2-25
System Inspection
....................................... 6-1 4
BATTERY NOT
CHARGING
............................. 3-54
Before Leaving on a Long Trip
......................... 4-34
System Warning Light
.................................. 3-34
Brake
Brake
Brake
2 Adjustment
............................................ 5-39
Fluid
.................................................... 5-36
Pedal. Throttle
....................................... 2-20 Brake Pedal Travel
......................................... 5-39
Brake Wear
................................................... 5-38
Brakes
.......................................................... 5-36
Braking
........................................................... 4-6
Braking in Emergencies
..................................... 4-8
Break-in, New Vehicle
..................................... 2-18
Bucket Seats, Rear
......................................... 1-22
Bulb Replacement
........................................... 5-49
Center High-Mounted Stoplamp (CHMSL)
........ 5-52
Front Turn Signal, Sidemarker and Daytime
Halogen Bulbs
............................................ 5-49
Headlamps
................................................. 5-49
Replacement Bulbs
...................... ........ 5-53
Taillamps
........................................ .... 5-52
Buying New Tires
....................................... 5-58
Running Lamps
........................................ 5-50
C
California Fuel ................................. .......... 5-6
Canada
........................................................... 7-4
Canadian Owners
................................................ ii
Canadian Roadside Assistance ........................... 7-7
Capacities and Specifications ............................ 5-96
Carbon Monoxide
................... 4-37, 4-47, 2.13, 2-29
Care
of
Safety Belts ............................. .... 5-80
Care
of Your
Cassette Tape Player
............................... 3-87
CD and DVD Player .................................... 3-89

Exit Lighting ........................................ 3-16
Extender, Safety Belt
....................................... 1-47
Exterior Lamps
......................... ~ ~ ................ 3-1 3
FabricKarpet
...
Engine Air Cleaner ..............................
Finding a P TY Station (RDS and XMTM) .....
Filter
Finding a Station
....................................
F
....
Finish Care
Finish Damage
................................
Fixed Mast Antenna .........................
Flash-to-Pass ...................................
Flat Tire .........................................
Flat Tire, Changing ..........................
Fluid
Automatic Transmission
.................
Power Steering ............................
Windshield Washer .......................
-
.....................................
..
.....
...
.... 5-78
.... 5-17
.... 3-63
.... 3-61
.... 5-81
.... 5-83
.... 3-89
...... 3-8
.... 5-63
............. 5-63
.......... 5-20
.......... 5-34
.......... 5-34
FM Stereo
..................................................... 3-87
Fog Lamps
.................................................... 3-1 5
Folding the Seatback ....................................... 1-17
Folding the Seatbacks
............................. 1-12, 1-22
Folding the Seatbacks (60/40 Split Bench Seat) .... 1-9
Following Distance
.......................................... 4-53
Footnotes
........................................ ......... 6-5
Front Axle
.................................... ... 5-47 Frontal
Air Bags
...................................... 1-77
Fuel
............................................................... 5-5
Additives ...................................................... 5-6
California Fuel
.............................................. 5-6
Filling Your Tank
........................................... 5-7
Fuels in Foreign Countries
.......................... 5-6
Gasoline Octane
....................................... 5-5
Gasoline Specifications .................................. 5-5
System Inspection ....................................... 6-14
Filling
a Portable Fuel Container
..................... 5-9
Gage
............................. .................... 3-42
Low Warning Light
....................................... 3-42
Fuel Information Button
.................................... 3-45
FUEL LEVEL LOW
......................................... 3-55
Fuses
Fuses and Circuit Breakers
........................... 5-87
Windshield Wiper
......................................... 5-87
G
Gage
Engine Coolant Temperature
............. .... 3-36
Fuel
...................................................... 3-42
Oil Pressure
........................................... 3-40
Speedometer
.......................................... 3-30
Tachometer
............................................. 3-30
Transmission Temperature
......................... 3-37
Voltmeter Gage ....................................... 3-34
Garage Door Opener
....................................... 2-38
6