2008 GMC YUKON XL towing

If you get the ENGINE OVERHEATED STOP ENGINE or
the ENGINE OVERHEATED IDLE ENGINE message
with no sign of steam, try this for a minute or so:
1. If the vehicle has an air conditioner and it is on,
turn it off.
2. Turn on the heater to the highest temperature and
at the highest fan speed and open the windows as
necessary.
3. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it is safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL (N) and let the
engine idle.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle immediately.
If there is still no sign of steam and your vehicle has an
engine-driven cooling fan, push down the accelerator
until the engine speed is about twice as fast as normal
idle speed for at least ve minutes while parked.
If there is still no sign of steam and your vehicle has an
electric cooling fan, idle the engine for ve minutes
while parked.If you still have the warning, turn off the engine and get
everyone out of the vehicle until it cools down. Also,
see “Overheated Engine Protection Operating Mode”
later in this section.
You might decide not to lift the hood but to get service
help right away.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
ENGINE POWER IS REDUCED message is displayed,
an overheat protection mode which alternates ring
groups of cylinders helps prevent engine damage. In this
mode, you will notice a loss in power and engine
performance. This operating mode allows your vehicle
to be driven to a safe place in an emergency. Driving
extended miles (km) and/or towing a trailer in the
overheat protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss, change the oil and
reset the oil life system. SeeEngine Oil on
page 5-15.
5-33

Engine Fan Noise
If 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.
If your vehicle has electric cooling fans, you may hear
the fans spinning at low speed during most everyday
driving. The fans may turn off if no cooling is required.
Under heavy vehicle loading, trailer towing, and/or
high outside temperatures, or if you are operating your
air conditioning system, the fans may change to
high speed and you may hear an increase in fan noise.
This is normal and indicates that the cooling system
is functioning properly. The fans will change to low
speed when additional cooling is no longer required.
Power Steering Fluid
SeeEngine Compartment
Overview on page 5-14for
reservoir location.
If your vehicle is a
Two-mode Hybrid, see
the Two-mode Hybrid
manual for more
information.
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.
5-39

(c)Visually inspect hoses and have them replaced if they
are cracked, swollen, or deteriorated. Inspect all pipes,
fittings, and clamps; replace with genuine parts as
needed. To help ensure proper operation, a pressure test
of the cooling system and pressure cap and cleaning the
outside of the radiator and air conditioning condenser is
recommended at least once a year.
(d)Inspect wiper blades for wear, cracking, or
contamination. Clean the windshield and wiper blades, if
contaminated. Replace wiper blades that are worn or
damaged. See Windshield Wiper Blade Replacement on
page 5-62andWindshield, Backglass, and Wiper
Blades on page 5-113 for more information.
(e)Make sure the safety belt reminder light and safety
belt assemblies 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 see Checking
the Restraint Systems on page 1-92.
(f)Lubricate all key lock cylinders, hood latch assembly,
secondary latch, pivots, spring anchor, release pawl,
rear compartment hinges, outer liftgate handle pivot
points, rear door detent link, roller mechanism, liftgate
handle pivot points, latch bolt, fuel door hinge, cargo
door hinge, locks, and folding seat hardware. More
frequent lubrication may be required when exposed to
a corrosive environment.Applying silicone grease on weatherstrips with a clean
cloth will make them last longer, seal better, and
not stick or squeak.
(g)Check vent hose at transfer case for kinks and
proper installation.
(h)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.
(i)Drain, flush, and refill cooling system. This service
can be complex; you should have your dealer/retailer
perform this service. See Engine Coolant on page 5-28
for what to use. Inspect hoses. Clean radiator,
condenser, pressure cap, and filler neck. Pressure test
the cooling system and pressure cap.
(j)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the fluid level checked. Add fluid if needed.
(k)Inspect 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.
6-8

Towing and Road Service Exclusions
Specically excluded from Roadside Assistance
coverage are towing or services for vehicles operated
on a non-public roadway or highway, nes, impound
towing caused by a violation of local, Municipal, State,
Provincial, or Federal law, and mounting, dismounting or
changing of snow tires, chains, or other traction
devices.
Roadside Assistance is not part of or included in the
coverage provided by the New Vehicle Limited Warranty.
GMC and General Motors of Canada Limited reserve
the right to make any changes or discontinue the
Roadside Assistance program at any time without
notication.
Scheduling Service Appointments
When your vehicle requires warranty service, contact
your dealer/retailer and request an appointment.
By scheduling a service appointment and advising your
service consultant of your transportation needs, your
dealer/retailer can help minimize your inconvenience.
If your vehicle cannot be scheduled into the service
department immediately, keep driving it until it can be
scheduled for service, unless, of course, the problem is
safety-related. If it is, please call your dealership/retailer,
let them know this, and ask for instructions.If the dealer/retailer requests that you simply drop the
vehicle off for service, you are urged to do so as early in
the work day as possible to allow for the same day repair.
Courtesy Transportation
To enhance your ownership experience, we and our
participating dealers are proud to offer Courtesy
Transportation, a customer support program for vehicles
with the Bumper to Bumper (Base Warranty Coverage
period in Canada) and extended powertrain warranty
in both the U.S. and Canada.
Several courtesy transportation options are available to
assist in reducing your inconvenience when warranty
repairs are required.
Courtesy Transportation is not a part of the New Vehicle
Limited Warranty. A separate booklet entitled “Warranty
and Owner Assistance Information” furnished with
each new vehicle provides detailed warranty coverage
information.
7-9

Insuring Your Vehicle
Protect your investment in your GM vehicle with
comprehensive and collision insurance coverage. There
are signicant differences in the quality of coverage
afforded by various insurance policy terms. Many
insurance policies provide reduced protection to your
GM vehicle by limiting compensation for damage repairs
by using aftermarket collision parts. Some insurance
companies will not specify aftermarket collision
parts. When purchasing insurance, we recommend that
you assure your vehicle will be repaired with GM
original equipment collision parts. If such insurance
coverage is not available from your current insurance
carrier, consider switching to another insurance carrier.
If your vehicle is leased, the leasing company may
require you to have insurance that assures repairs with
Genuine GM Original Equipment Manufacturer (OEM)
parts or Genuine Manufacturer replacement parts. Read
your lease carefully, as you may be charged at the
end of your lease for poor quality repairs.
If a Crash Occurs
Here is what to do if you are involved in a crash.
Try to relax and then check to make sure you are all
right. If you are uninjured, make sure that no one else
in your vehicle, or the other vehicle, is injured.
If there has been an injury, call emergency services
for help. Do not leave the scene of a crash until all
matters have been taken care of. Move your vehicle
only if its position puts you in danger or you are
instructed to move it by a police officer.
Give only the necessary and requested information
to police and other parties involved in the crash. Do
not discuss your personal condition, mental frame of
mind, or anything unrelated to the crash. This will
help guard against post-crash legal action.
If you need roadside assistance, call GM Roadside
Assistance. SeeRoadside Assistance Program on
page 7-6for more information.
If your vehicle cannot be driven, know where the
towing service will be taking it. Get a card from the
tow truck operator or write down the driver’s name,
the service’s name, and the phone number.
Remove any valuables from your vehicle before it is
towed away. Make sure this includes your insurance
information and registration if you keep these items
in your vehicle.
7-12

Power (cont.)
Running Boards..........................................2-18
Seat............................................................ 1-3
Steering Fluid.............................................5-39
Windows....................................................2-20
Privacy..........................................................7-16
Event Data Recorders..................................7-16
Navigation System.......................................7-17
OnStar.......................................................7-17
Radio Frequency Identication.......................7-17
Programmable Automatic Door Locks.................2-11
R
Radio Frequency Identication (RFID), Privacy....7-17
Radios..........................................................3-81
Radio(s)........................................................3-84
Radios
Navigation/Radio System, see Navigation
Manual.................................................3-114
Rear Seat Audio........................................3-125
Reception.................................................3-129
Setting the Clock.........................................3-82
Theft-Deterrent..........................................3-127
Rainsense™ II Wipers.....................................3-10
Reading Lamps..............................................3-21
Rear Air Conditioning and Heating System.........3-33
Rear Air Conditioning and Heating System and
Electronic Climate Controls...........................3-35Rear Axle......................................................5-52
Locking........................................................ 4-6
Rear Door Security Locks................................2-12
Rear Heated Seats.........................................1-11
Rear Seat Armrest..........................................2-73
Rear Seat Audio (RSA)..................................3-125
Rear Seat Entertainment System.....................3-115
Rear Side Window Antenna............................3-130
Rear Storage Area..........................................2-73
Rear Windshield Washer/Wiper.........................3-12
Rearview Mirror, Automatic Dimming with
Compass and Temperature Display................2-52
Rearview Mirror, Automatic Dimming with OnStar
®,
Compass and Temperature Display..................2-49
Reclining Seatbacks.......................................... 1-8
Recommended Fluids and Lubricants.................6-13
Recovery Hooks.............................................4-34
Recreational Vehicle Towing.............................4-45
Remote Keyless Entry (RKE) System.................. 2-4
Remote Keyless Entry (RKE) System, Operation..... 2-5
Remote Vehicle Start........................................ 2-8
Removing the Flat Tire and Installing the
Spare Tire..................................................5-94
Removing the Spare Tire and Tools...................5-90
Replacement Bulbs.........................................5-61
Replacement Parts, Maintenance......................6-15
Reporting Safety Defects
Canadian Government..................................7-14
General Motors...........................................7-14
United States Government............................7-14
10

Tires (cont.)
Removing the Spare Tire and Tools...............5-90
Secondary Latch System............................5-100
Spare Tire................................................5-107
Storing a Flat or Spare Tire and Tools..........5-103
Tire Sidewall Labeling..................................5-65
Tire Terminology and Denitions....................5-69
Uniform Tire Quality Grading.........................5-83
Wheel Alignment and Tire Balance.................5-84
Wheel Replacement.....................................5-85
When It Is Time for New Tires......................5-80
Tow/Haul Mode...............................................2-37
Tow/Haul Mode Light.......................................3-53
Towing
Recreational Vehicle.....................................4-45
Towing a Trailer..........................................4-49
Your Vehicle...............................................4-45
Traction
StabiliTrak
®System....................................... 4-6
Trailer
Recommendations.......................................4-63
Transmission
Fluid, Automatic..................................5-22, 5-24
Transmission Operation, Automatic....................2-31
Trip Odometer................................................3-39
Turn and Lane-Change Signals.......................... 3-8
Turn Signal/Multifunction Lever........................... 3-7
U
Ultrasonic Rear Parking Assist (URPA)...............2-58
Uniform Tire Quality Grading............................5-83
Universal Home Remote System.......................2-64
Operation...................................................2-64
Using this Manual............................................... iii
V
Vehicle
Control........................................................ 4-3
Damage Warnings........................................... iv
Loading......................................................4-35
Symbols......................................................... iv
Vehicle Customization, DIC..............................3-72
Vehicle Data Recording and Privacy..................7-16
Vehicle Identication
Number (VIN)............................................5-116
Service Parts Identication Label..................5-116
Vehicle, Remote Start....................................... 2-8
Ventilation Adjustment......................................3-33
Visors...........................................................2-21
Voltmeter Gage..............................................3-44
13