maintenance GMC YUKON DENALI 2008 Owners Manual

Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-2
Rear Seats
............................................... 1-9
Safety Belts
.............................................1-28
Child Restraints
.......................................1-49
Airbag System
.........................................1-75
Restraint System Check
............................1-92
Features and Controls..................................... 2-1
Keys
........................................................ 2-3
Doors and Locks
......................................2-10
Windows
.................................................2-19
Theft-Deterrent Systems
............................2-21
Starting and Operating Your Vehicle
...........2-25
Mirrors
....................................................2-40
Object Detection Systems
..........................2-44
OnStar
®System
......................................2-47
Universal Home Remote System
................2-50
Storage Areas
.........................................2-58
Sunroof
..................................................2-62
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-4
Climate Controls
......................................3-23
Warning Lights, Gages, and Indicators
........3-31
Driver Information Center (DIC)
..................3-49
Audio System(s)
.......................................3-73Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-40
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-3
Fuel
......................................................... 5-5
Checking Things Under the Hood
...............5-10
All-Wheel Drive
........................................5-45
Rear Axle
...............................................5-46
Front Axle
...............................................5-47
Headlamp Aiming
.....................................5-48
Bulb Replacement
....................................5-50
Windshield Wiper Blade Replacement
.........5-53
Tires
......................................................5-55
Appearance Care
.....................................5-98
Vehicle Identication
...............................5-107
Electrical System
....................................5-108
Capacities and Specications
...................5-114
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance Information.................... 7-1
Customer Assistance and Information
........... 7-2
Reporting Safety Defects
...........................7-13
Vehicle Data Recording and Privacy
...........7-15
Index.................................................................1
2008 GMC Yukon Denali/Yukon XL Denali Owner ManualM

Restraint System Check
Checking the Restraint Systems
Safety Belts
Now and then, 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. Torn or
frayed safety belts may not protect you in a crash.
They can rip apart under impact forces. If a belt is torn
or frayed, get a new one right away.
Make sure the safety belt reminder light is working. See
Safety Belt Reminders on page 3-33for more
information.
Keep safety belts clean and dry. SeeCare of Safety
Belts on page 5-101.
Airbags
The airbag system does not need regularly scheduled
maintenance or replacement. Make sure the airbag
readiness light is working. SeeAirbag Readiness Light
on page 3-34for more information.
Notice:If an airbag covering is damaged, opened,
or broken, the airbag may not work properly. Do
not open or break the airbag coverings. If there are
any opened or broken airbag covers, have the
airbag covering and/or airbag module replaced. For
the location of the airbag modules, seeWhat
Makes an Airbag Inflate? on page 1-83. See your
dealer/retailer for service.
1-92

Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation of
the fuel, ignition, and emission control systems. It makes
sure that emissions are at acceptable levels for the life of
the vehicle, helping to produce a cleaner environment.
The check engine light
comes on to indicate that
there is an OBD II
problem and service is
required.
Malfunctions often are indicated by the system before
any problem is apparent. This can prevent more serious
damage to your vehicle. This system is also designed
to assist your service technician in correctly diagnosing
any malfunction.
Notice:If you keep driving your vehicle with this
light on, after a while, the emission controls
might not work as well, your vehicle’s fuel economy
might not be as good, and the engine might not
run as smoothly. This could lead to costly repairs
that might not be covered by your warranty.Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of
your vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and can cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This could
also result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 5-3.
This light comes on, as a check to show it is working,
when the ignition is turned ON/RUN but the engine is not
running. If the light does not come on, have it repaired.
This light also comes on during a malfunction in
one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and could damage the emission control system on
your vehicle. Diagnosis and service might be
required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service might be required.
3-42

If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer/retailer can check the vehicle. Your
dealer/retailer has the proper test equipment and
diagnostic tools to x any mechanical or electrical
problems that might have developed.
Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
might begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the check
engine light is on or not working properly.Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen if
you have recently replaced the battery or if the
battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This can take several days
of routine driving. If you have done this and your vehicle
still does not pass the inspection for lack of OBD
system readiness, your dealer/retailer can prepare the
vehicle for inspection.
3-44

Oil Pressure Gage
The oil pressure gage shows the engine oil pressure
in psi (pounds per square inch) when the engine
is running. Canadian vehicles indicate pressure in
kPa (kilopascals).Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
When the oil pressure reaches the low pressure
zone, the “OIL PRESSURE LOW STOP ENGINE”
message will appear in the Driver Information Center.
SeeDIC Warnings and Messages on page 3-56
andEngine Oil on page 5-13for more information.
A reading in the low pressure zone may be caused by a
dangerously low oil level or some other problem causing
low oil pressure. Check your oil as soon as possible.
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be covered
by your warranty. Always follow the maintenance
schedule in this manual for changing engine oil. United States
Canada
3-45

Oil Pressure Light
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be
covered by your warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.This light will come on
briey when you start your
engine. If it does not,
have your vehicle serviced.
When the light comes on and stays on, it means that oil
is not owing through your engine properly. You
could be low on oil and you might have some other
system problem.
Security Light
For information regarding
this light and the vehicle’s
security system, see
Content Theft-Deterrent on
page 2-22.
3-46

When the remaining oil life is low, the CHANGE
ENGINE OIL SOON message will appear on the display.
See “CHANGE ENGINE OIL SOON” underDIC
Warnings and Messages on page 3-56. You should
change the oil as soon as you can. SeeEngine Oil on
page 5-13. In addition to the engine oil life system
monitoring the oil life, additional maintenance is
recommended in the Maintenance Schedule in this
manual. SeeScheduled Maintenance on page 6-4for
more information.
Remember, you must reset the OIL LIFE display
yourself after each oil change. It will not reset itself.
Also, be careful not to reset the OIL LIFE display
accidentally at any time other than when the oil has just
been changed. It cannot be reset accurately until the
next oil change. To reset the engine oil life system, see
Engine Oil Life System on page 5-16.
Units
Press the vehicle information button until UNITS
displays. This display allows you to select between
English or Metric units of measurement. Once in this
display, press the set/reset button to select between
ENGLISH or METRIC units. All of the vehicle information
will then be displayed in the unit of measurement
selected.
Tire Pressure
The pressure for each tire can be viewed in the DIC.
The tire pressure will be shown in either pounds
per square inch (psi) or kilopascals (kPa). Press the
vehicle information button until the DIC displays FRONT
TIRES PSI (kPa) LEFT ## RIGHT ##. Press the
vehicle information button again until the DIC displays
REAR TIRES PSI (kPa) LEFT ## RIGHT ##.
If a low or high tire pressure condition is detected by the
system while driving, a message advising you to
check the pressure in a specic tire will appear in the
display. SeeInflation - Tire Pressure on page 5-60and
DIC Warnings and Messages on page 3-56for more
information.
If the tire pressure display shows dashes instead of a
value, there may be a problem with your vehicle. If this
consistently occurs, see your dealer/retailer for service.
Engine Hours
Press the vehicle information button until ENGINE
HOURS displays. This display shows the total number
of hours the engine has run.
3-53

DIC Warnings and Messages
Messages are displayed on the DIC to notify the driver
that the status of the vehicle has changed and that
some action may be needed by the driver to correct the
condition. Multiple messages may appear one after
another.
Some messages may not require immediate action, but
you can press any of the DIC buttons on the instrument
panel or the trip odometer reset stem on the instrument
panel cluster to acknowledge that you received the
messages and to clear them from the display.
Some messages cannot be cleared from the DIC
display because they are more urgent. These messages
require action before they can be cleared. You should
take any messages that appear on the display seriously
and remember that clearing the messages will only
make the messages disappear, not correct the problem.
The following are the possible messages that can be
displayed and some information about them.
CHANGE ENGINE OIL SOON
This message displays when the engine oil needs to be
changed. When you change the engine oil, be sure
to reset the CHANGE ENGINE OIL SOON message.
SeeEngine Oil Life System on page 5-16for information
on how to reset the message. SeeEngine Oil on
page 5-13andScheduled Maintenance on page 6-4for
more information.
CHECK TIRE PRESSURE
This message displays when the pressure in one or
more of the vehicle’s tires needs to be checked.
This message also displays LEFT FRONT, RIGHT
FRONT, LEFT REAR, or RIGHT REAR to indicate which
tire needs to be checked. You can receive more than
one tire pressure message at a time. To read the other
messages that may have been sent at the same
time, press the set/reset button or the trip odometer
reset stem. If a tire pressure message appears on the
DIC, stop as soon as you can. Have the tire pressures
checked and set to those shown on the Tire Loading
Information label. SeeTires on page 5-55,Loading Your
Vehicle on page 4-34, andInflation - Tire Pressure on
page 5-60. The DIC also shows the tire pressure values.
See “DIC Operation and Displays (Using DIC Buttons)”
earlier in this section. If the tire pressure is low, the
low tire pressure warning light comes on. SeeTire
Pressure Light on page 3-41.
3-56

The following steps must be performed on the bolts and
snap features to remove the air dam:
1. Remove the two outboard air dam bolts.
2. With a at-blade screwdriver, push down on the
snap features and disengage the snaps.
3. After the bolts are removed and the snaps are
disengaged, push forward on the air dam until it
is free.
When you are back on roads, though, be sure to
replace the air dam.
Notice:Operating your vehicle for extended
periods without the front fascia lower air dam
installed can cause improper air ow to the engine.
Always be sure to replace the front fascia air
dam when you are nished off-road driving.
To reinstall the lower air dam do the following:
1. Line up the snap features and push the air dam
rearward to engage the snaps.
2. Install the two outboard bolts.Before You Go Off-Roading
There are some things to do before you go out. For
example, be sure to have all necessary maintenance
and service work done. Check to make sure all
underbody shields, if the vehicle has them, are properly
attached. Is there enough fuel? Is the spare tire fully
inated? Are the uid levels up where they should be?
What are the local laws that apply to off-roading
where you will be driving? If you do not know, you
should check with law enforcement people in the area.
Will you be on someone’s private land? If so, be
sure to get the necessary permission.
4-14

If the water is not too deep, drive slowly through it. At
faster speeds, water splashes on the ignition system and
your vehicle can stall. Stalling can also occur if you
get the tailpipe under water. And, as long as the tailpipe
is under water, you will never be able to start the
engine. When you go through water, remember that
when the brakes get wet, it may take you longer to stop.
{CAUTION:
Driving through rushing water can be
dangerous. Deep water can sweep your vehicle
downstream and you and your passengers
could drown. If it is only shallow water, it can
still wash away the ground from under your
tires, and you could lose traction and roll the
vehicle over. Do not drive through rushing
water.
SeeDriving in Rain and on Wet Roads on page 4-26for
more information on driving through water.
After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis, or under the hood. These
accumulations can be a re hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the body structure,
steering, suspension, wheels, tires, and exhaust
system for damage. Also, check the fuel lines and
cooling system for any leakage.
Your vehicle will require more frequent service due to
off-road use. Refer to the Maintenance Schedule
for additional information.
Driving at Night
Night driving is more dangerous than day driving because
some drivers are likely to be impaired — by alcohol or
drugs, with night vision problems, or by fatigue.
4-25