2004 GMC YUKON Power steering

Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the
clutch is engaged, the fan spins faster to provide more air
to cool the engine. In most everyday driving conditions,
the fan is spinning slower and the clutch is not fully
engaged. This improves fuel economy and reduces fan
noise. Under heavy vehicle loading, trailer towing and/or
high outside temperatures, the fan speed increases as
the clutch more fully engages. So you may hear an
increase in fan noise. This is normal and should not be
mistaken as the transmission slipping or making extra
shifts. It is merely the cooling system functioning properly.
The fan will slow down when additional cooling is not
required and the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch partially
disengages.
Power Steering Fluid
8100 Engines
5-38

When to Check Power Steering Fluid
It is not necessary to regularly check power steering uid
unless you suspect there is a leak in the system or
you hear an unusual noise. A uid loss in this system
could indicate a problem. Have the system inspected
and repaired. SeeEngine Compartment Overview
on page 5-12for reservoir location.
How to Check Power Steering Fluid
Turn the key off, let the engine compartment cool down,
wipe the cap and the top of the reservoir clean, then
unscrew the cap and wipe the dipstick with a clean rag.
Replace the cap and completely tighten it. Then
remove the cap again and look at the uid level on the
dipstick.
The level should be at the FULL COLD mark. If
necessary, add only enough uid to bring the level up to
the mark.
What to Use
To determine what kind of uid to use, see
Recommended Fluids and Lubricants on page 6-12.
Always use the proper uid. Failure to use the proper
uid can cause leaks and damage hoses and seals. All Other Engines
5-39

Tire Terminology and Denitions
Air Pressure:The amount of air inside the tire pressing
outward on each square inch of the tire. Air pressure
is expressed in pounds per square inch (psi) or
kilopascal (kPa).
Accessory Weight:This means the combined weight
of optional accessories. Some examples of optional
accessories are, automatic transmission, power steering,
power brakes, power windows, power seats, and air
conditioning.
Aspect Ratio:The relationship of a tire’s height to
its width.
Belt:A rubber coated layer of cords that is located
between the plies and the tread. Cords may be made
from steel or other reinforcing materials.
Bead:The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Bias Ply Tire:A pneumatic tire in which the plies are
laid at alternate angles less than 90 degrees to the
centerline of the tread.Cold Ination Pressure:The amount of air pressure in
a tire, measured in pounds per square inch (psi) or
kilopascals (kPa) before a tire has built up heat
from driving. SeeInation - Tire Pressure on page 5-72.
Curb Weight:This means the weight of a motor
vehicle with standard and optional equipment including
the maximum capacity of fuel, oil and coolant, but
without passengers and cargo.
DOT Markings:A code molded into the sidewall of a
tire signifying that the tire is in compliance with the U.S.
Department of Transportation motor vehicle safety
standards. The DOT code includes the Tire Identication
Number (TIN), an alphanumeric designator which can
also identify the tire manufacturer, production plant,
brand and date of production.
GVWR:Gross Vehicle Weight Rating, seeLoading
Your Vehicle on page 4-56.
GAWR FRT:Gross Axle Weight Rating for the front
axle, seeLoading Your Vehicle on page 4-56.
GAWR RR:Gross Axle Weight Rating for the rear axle,
seeLoading Your Vehicle on page 4-56.
5-69

Center Instrument Panel Fuse Block
The center instrument panel utility block is located
underneath the instrument panel, to the left of the
steering column.
Device Usage
SEO Special Equipment Option
TRAILER Trailer Brake Wiring
UPFIT Uptter (Not Used)
Device Usage
SL RIDERide Control Harness
Connection
HDLR 2 Headliner Wiring Connector
BODY Body Wiring Connector
DEFOG Rear Defogger Relay
HDLNR 1 Headliner Wiring Connector 1
SPARE RELAY Not Used
CB SEATDriver and Passenger Seat
Module Circuit Breaker
CB RT DOORRight Power Window Circuit
Breaker
SPARE Not Used
INFOInfotainment Harness
Connection
5-116

Additional Required Services (cont’d)
Service25,000
(41 500)50,000
(83 000)75,000
(125 000)100,000
(166 000)125,000
(207 500)150,000
(240 000)
Replace spark plugs and inspect
spark plug wires.An Emission
Control Service.•
Engine cooling system service (or
every 5 years, whichever occurs
rst).An Emission Control Service.
See footnote (i).•
Inspect engine accessory drive belt.
An Emission Control Service.•
Maintenance Footnotes
†The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle’s useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.
#Lubricate the front suspension, ball joints, steering
linkage, transmission shift linkage and parking
brake cable guides. Ball joints should not be lubricated
unless their temperature is 10°F (-12°C) or higher,
or they could be damaged.(a)Visually inspect brake lines and hoses for proper
hook-up, binding, leaks, cracks, chang, etc. Inspect
disc brake pads for wear and rotors for surface
condition. Inspect other brake parts, including calipers,
parking brake, etc.
(b)Visually inspect front and rear suspension and
steering system for damaged, loose or missing parts,
signs of wear or lack of lubrication. Inspect power
steering lines and hoses for proper hook-up, binding,
leaks, cracks, chang, etc. Visually check constant
velocity joints, rubber boots and axle seals for leaks.
6-7

Recommended Fluids and
Lubricants
Fluids and lubricants identied below by name, part
number or specication may be obtained from your
dealer.
Usage Fluid/Lubricant
Engine OilEngine oil which meets GM
Standard GM6094M and displays
the American Petroleum Institute
Certied for Gasoline Engines
starburst symbol. To determine the
proper viscosity for your vehicle’s
engine, seeEngine Oil on
page 5-16.
Engine Coolant50/50 mixture of clean, drinkable
water and use only
DEX-COOL
®Coolant. SeeEngine
Coolant on page 5-26.
Hydraulic Brake
SystemDelco Supreme 11 Brake Fluid or
equivalent DOT-3 brake uid.
Usage Fluid/Lubricant
Windshield
Washer SolventGM Optikleen
®Washer Solvent.
Power Steering
SystemGM Power Steering Fluid (GM Part
No. U.S. 89021184, in Canada
89021186).
Automatic
TransmissionDEXRON
®-III Automatic
Transmission Fluid.
Key Lock
CylindersMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241, in
Canada 10953474).
Chassis
LubricationChassis Lubricant (GM Part No.
U.S. 12377985, in Canada
88901242) or lubricant meeting
requirements of NLGI #2, Category
LB or GC-LB.
Front Axle
(Four-Wheel
Drive)SAE 80W-90 Axle Lubricant (GM
Part No. U.S. 1052271, in Canada
10950849).
6-12

A
Accessory Power Outlets.................................3-21
Adding Washer Fluid.......................................5-40
Additional Program Information........................... 7-9
Additives, Fuel................................................. 5-6
Add-On Electrical Equipment...........................5-113
Adjustable Throttle and Brake Pedal..................2-23
Adjusting the Speakers
(Balance/Fade)..................3-80, 3-84, 3-96, 3-111
After Off-Road Driving.....................................4-36
Air Bag
Passenger Status Indicator...........................3-43
Readiness Light..........................................3-43
Air Bag Systems.....................................1-72, 1-78
Adding Equipment to Your Air Bag-Equipped
Vehicle...................................................1-86
How Does an Air Bag Restrain?....................1-79
Passenger Sensing System...........................1-82
Servicing Your Air Bag-Equipped Vehicle.........1-86
What Makes an Air Bag Inate?....................1-79
What Will You See After an Air Bag
Inates?..................................................1-80
When Should an Air Bag Inate?...................1-77
Where Are the Air Bags?..............................1-75
Air Cleaner/Filter, Engine.................................5-21
Air Conditioning..............................................3-31
Airbag Sensing and Diagnostic Module (SDM).......7-10
All Overseas Locations...................................... 7-5
All-Wheel Drive...............................................5-51All-Wheel Drive with Stabilitrak
®........................2-33
AM .............................................................3-137
AM-FM Radio.................................................3-78
Antenna, Fixed Mast......................................3-139
Antenna, XM™ Satellite Radio Antenna
System.....................................................3-139
Anti-lock Brake System..................................... 4-7
Anti-Lock Brake, System Warning Light..............3-47
Appearance Care..........................................5-103
Care of Safety Belts...................................5-106
Chemical Paint Spotting..............................5-110
Cleaning the Inside of Your Vehicle..............5-104
Cleaning the Outside of Your Vehicle............5-107
Finish Damage..........................................5-109
Sheet Metal Damage..................................5-109
Underbody Maintenance.............................5-109
Vehicle Care/Appearance Materials...............5-110
Weatherstrips............................................5-106
Approaching a Hill..........................................4-28
Ashtrays........................................................3-21
Audio Output................................................3-131
Audio System(s).............................................3-77
AM-FM Radio.............................................3-78
Audio Steering Wheel Controls....................3-136
Care of Your Cassette Tape Player...............3-137
Care of Your CD and DVD Player................3-139
Care of Your CDs and DVDs.......................3-138
Chime Level Adjustment.............................3-139
Fixed Mast Antenna...................................3-139
Radio with Cassette and CD.........................3-92
1

EEasy Exit Seat...............................................2-65
Electrical System
Add-On Equipment.....................................5-113
Fuses and Circuit Breakers.........................5-113
Power Windows and Other Power Options.......5-113
Windshield Wiper Fuses.............................5-113
Emissions Inspection and Maintenance
Programs...................................................3-54
Engine
Air Cleaner/Filter.........................................5-21
Battery.......................................................5-44
Check and Service Engine Soon Light............3-51
Coolant......................................................5-26
Coolant Heater............................................2-23
Coolant Temperature Gage...........................3-49
Engine Compartment Overview......................5-12
Exhaust.....................................................2-42
Fan Noise..................................................5-38
Oil .............................................................5-16
Overheating................................................5-29
Starting......................................................2-22
ENGINE COOLANT HOT.................................3-71
Engine Hour Meter Display...............................3-42
Engine Oil Additives........................................5-19
ENGINE OVERHEATED..................................3-72
Entertainment System
Cleaning the Video Screen..........................3-139
DVD Distortion..........................................3-137Entry Lighting.................................................3-19
Environmental Concerns..................................4-25
Erasing HomeLink®Buttons..............................2-58
Event Data Records (EDR)..............................7-10
Exit Lighting...................................................3-19
Express-Down Windows...................................2-16
Extender, Safety Belt.......................................1-44
Exterior Lamps...............................................3-15
F
Filter
Engine Air Cleaner......................................5-21
Finding a Program Type (PTY) Station
(RDS and XM™).......................3-85, 3-96, 3-112
Finding a Station..................3-79, 3-83, 3-94, 3-110
Finish Care..................................................5-107
Finish Damage.............................................5-109
Fixed Mast Antenna.......................................3-139
Flash-to-Pass................................................... 3-9
Flat Tire........................................................5-83
Flat Tire, Changing.........................................5-84
Fluid
Automatic Transmission................................5-23
Power Steering...........................................5-38
Windshield Washer......................................5-40
FM Stereo....................................................3-137
Fog Lamps....................................................3-18
6