2008 GMC YUKON DENALI maintenance schedule

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

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

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

Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake and shift into PARK (P).
5. Release the regular brakes.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
start your engine,
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission uid (don’t overll),
engine oil, axle lubricant, belts, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help you nd them quickly. If
you’re trailering, it’s a good idea to review these sections
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
4-53