roof GMC ENVOY 2008 Owner's Manual

Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-2
Rear Seats
..............................................1-11
Safety Belts
.............................................1-13
Child Restraints
.......................................1-32
Airbag System
.........................................1-53
Restraint System Check
............................1-68
Features and Controls..................................... 2-1
Keys
........................................................ 2-3
Doors and Locks
....................................... 2-7
Windows
.................................................2-13
Theft-Deterrent Systems
............................2-16
Starting and Operating Your Vehicle
...........2-20
Mirrors
....................................................2-39
OnStar
®System
......................................2-48
Universal Home Remote System
................2-52
Storage Areas
.........................................2-57
Sunroof
..................................................2-60
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-4
Climate Controls
......................................3-21
Warning Lights, Gages, and Indicators
........3-30
Driver Information Center (DIC)
..................3-49
Audio System(s)
.......................................3-65Driving 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
Rear Axle
...............................................5-46
Four-Wheel Drive
.....................................5-47
Front Axle
...............................................5-48
Headlamp Aiming
.....................................5-49
Bulb Replacement
....................................5-49
Windshield Wiper Blade Replacement
.........5-54
Tires
......................................................5-57
Appearance Care
...................................5-100
Vehicle Identication
...............................5-108
Electrical System
....................................5-109
Capacities and Specications
...................5-120
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance Information.................... 7-1
Customer Assistance and Information
........... 7-2
Reporting Safety Defects
...........................7-15
Vehicle Data Recording and Privacy
...........7-18
Index................................................................ 1
2008 GMC Envoy and Envoy Denali Owner ManualM

If a child restraint has been installed and the on
indicator is lit, turn the vehicle off. Remove the child
restraint from the vehicle and reinstall the child restraint.
If, after reinstalling the child restraint and restarting
the vehicle, the on indicator is still lit, check to make
sure that the vehicle’s seatback is not pressing the child
restraint into the seat cushion. If this happens, slightly
recline the vehicle’s seatback and adjust the seat
cushion if possible. Also make sure the child restraint
is not trapped under the vehicle head restraint.
If this happens, adjust the head restraint.
Remove any additional material from the seat such as
blankets, cushions, seat covers, seat heaters or seat
massagers before reinstalling or securing the child
restraint.
If the on indicator is still lit, secure the child in the child
restraint in a rear seat position in the vehicle and
check with your dealer/retailer.
To remove the child restraint, unbuckle the vehicle’s
safety belt and let it go back all the way.Airbag System
Your vehicle has the following airbags:
A frontal airbag for the driver.
A frontal airbag for the right front passenger.
A roof-rail airbag for the driver and the passenger
seated directly behind the driver.
A roof-rail airbag for the right front passenger and
the passenger seated directly behind the right
front passenger.
All of the airbags in your vehicle will have the word
AIRBAG embossed in the trim or on an attached label
near the deployment opening.
For frontal airbags, the word AIRBAG will appear on
the middle part of the steering wheel for the driver and
on the instrument panel for the right front passenger.
With roof-rail airbags, the word AIRBAG will appear
along the headliner or trim.
Airbags are designed to supplement the protection
provided by safety belts. Even though today’s airbags
are also designed to help reduce the risk of injury
from the force of an inating bag, all airbags must
inate very quickly to do their job.
1-53

Here are the most important things to know about the
airbag system:
{CAUTION:
You can be severely injured or killed in a crash
if you are not wearing your safety belt — even
if you have airbags. Wearing your safety belt
during a crash helps reduce your chance of
hitting things inside the vehicle or being
ejected from it. Airbags are “supplemental
restraints” to the safety belts. All airbags are
designed to work with safety belts, but do not
replace them.
{CAUTION:
Frontal airbags are designed to deploy in
moderate to severe frontal and near frontal
crashes. They are not designed to inate in
rollover, rear crashes, or in many side crashes.
Rollover capable roof-rail airbags are designed
to inate in moderate to severe crashes where
something hits the side of your vehicle and in
the event of a vehicle rollover. They are not
designed to inate in frontal or in rear crashes.
Everyone in your vehicle should wear a safety
belt properly — whether or not there is an
airbag for that person.
1-54

{CAUTION:
Airbags inate with great force, faster than
the blink of an eye. Anyone who is up against,
or very close to, any airbag when it inates
can be seriously injured or killed. Do not sit
unnecessarily close to the airbag, as you would
be if you were sitting on the edge of your seat or
leaning forward. Safety belts help keep you in
position before and during a crash. Always wear
your safety belt, even with airbags. The driver
should sit as far back as possible while still
maintaining control of the vehicle.
Occupants should not lean on or sleep against
the door or side windows in seating positions
with roof-rail airbags.
{CAUTION:
Airbags plus lap-shoulder belts offer the
best protection for adults, but not for young
children and infants. Neither the vehicle’s
safety belt system nor its airbag system is
designed for them. Young children and infants
need the protection that a child restraint
system can provide. Always secure children
properly in your vehicle. To read how, see
Older Children on page 1-32orInfants and
Young Children on page 1-35.
There is an airbag
readiness light on the
instrument panel cluster,
which shows the airbag
symbol.
The system checks the airbag electrical system for
malfunctions. The light tells you if there is an electrical
problem. SeeAirbag Readiness Light on page 3-33
for more information.
1-55

The roof-rail airbags for the driver, right front passenger,
and second row outboard passengers are in the
ceiling above the side windows.
{CAUTION:
If something is between an occupant and an
airbag, the airbag might not inate properly
or it might force the object into that person
causing severe injury or even death. The path
of an inating airbag must be kept clear.
Do not put anything between an occupant and
an airbag, and do not attach or put anything
on the steering wheel hub or on or near any
other airbag covering.
If your vehicle has roof-rail airbags, never
secure anything to the roof of your vehicle by
routing the rope or tie down through any door
or window opening. If you do, the path of an
inating roof-rail airbag will be blocked. Driver Side shown, Passenger Side similar
1-57

When Should an Airbag Inate?
Frontal airbags are designed to inate in moderate to
severe frontal or near-frontal crashes to help reduce the
potential for severe injuries mainly to the driver’s or right
front passenger’s head and chest. However, they are only
designed to inate if the impact exceeds a predetermined
deployment threshold. Deployment thresholds are used
to predict how severe a crash is likely to be in time for the
airbags to inate and help restrain the occupants.
Whether your frontal airbags will or should deploy is not
based on how fast your vehicle is traveling. It depends
largely on what you hit, the direction of the impact,
and how quickly your vehicle slows down.
Frontal airbags may inate at different crash speeds.
For example:
If the vehicle hits a stationary object, the airbags
could inate at a different crash speed than if the
vehicle hits a moving object.
If the vehicle hits an object that deforms, the
airbags could inate at a different crash speed than
if the vehicle hits an object that does not deform.
If the vehicle hits a narrow object (like a pole), the
airbags could inate at a different crash speed
than if the vehicle hits a wide object (like a wall).
If the vehicle goes into an object at an angle, the
airbags could inate at a different crash speed
than if the vehicle goes straight into the object.Thresholds can also vary with specic vehicle design.
Frontal airbags are not intended to inate during vehicle
rollovers, rear impacts, or in many side impacts.
In addition, your vehicle has dual-stage frontal airbags.
Dual-stage airbags adjust the restraint according to
crash severity. Your vehicle has electronic frontal
sensors, which help the sensing system distinguish
between a moderate frontal impact and a more severe
frontal impact. For moderate frontal impacts, dual-stage
airbags inate at a level less than full deployment.
For more severe frontal impacts, full deployment occurs.
Your vehicle has seat position sensors which enables
the sensing system to monitor the position of the driver’s
and right front passenger’s seat. The sensors provide
information that is used to determine if the airbags
should deploy at a reduced level or at full deployment.
Your vehicle has roof-rail airbags. SeeAirbag System
on page 1-53. Roof-rail airbags are intended to inate
in moderate to severe side crashes. In addition,
these roof-rail airbags are intended to inate during a
rollover. Roof-rail airbags will inate if the crash severity
is above the system’s designed threshold level. The
threshold level can vary with specic vehicle design.
Roof-rail airbags are not intended to inate in frontal
impacts, near-frontal impacts, or rear impacts.
Both roof-rail airbags will deploy when either side
of the vehicle is struck or if the sensing system
predicts that the vehicle is about to roll over.
1-58

In any particular crash, no one can say whether an
airbag should have inated simply because of the
damage to a vehicle or because of what the repair
costs were. For frontal airbags, ination is determined
by what the vehicle hits, the angle of the impact,
and how quickly the vehicle slows down. For roof-rail
airbags, deployment is determined by the location
and severity of the side impact. In a rollover event,
roof-rail airbag deployment is determined by the
direction of the roll.
What Makes an Airbag Inate?
In a deployment event, the sensing system sends
an electrical signal triggering a release of gas from
the inator. Gas from the inator lls the airbag causing
the bag to break out of the cover and deploy. The
inator, the airbag, and related hardware are all part
of the airbag module.
Frontal airbag modules are located inside the steering
wheel and instrument panel. For vehicles with roof-rail
airbags, there are airbag modules in the ceiling of the
vehicle, near the side windows that have occupant
seating positions.
How Does an Airbag Restrain?
In moderate to severe frontal or near frontal collisions,
even belted occupants can contact the steering wheel
or the instrument panel. In moderate to severe side
collisions, even belted occupants can contact the inside
of the vehicle.
Airbags supplement the protection provided by safety
belts. Frontal airbags distribute the force of the impact
more evenly over the occupant’s upper body, stopping
the occupant more gradually. Roof-rail airbags distribute
the force of the impact more evenly over the occupant’s
upper body.
Rollover capable roof-rail airbags are designed to
help contain the head and chest of occupants in the
outboard seating positions in the rst and second rows.
The rollover capable roof-rail airbags are designed to
help reduce the risk of full or partial ejection in rollover
events, although no system can prevent all such
ejections.
But airbags would not help in many types of collisions,
primarily because the occupant’s motion is not toward
those airbags. SeeWhen Should an Airbag Inflate? on
page 1-58for more information.
Airbags should never be regarded as anything more
than a supplement to safety belts.
1-59

What Will You See After an Airbag
Inates?
After the frontal airbags inate, they quickly deate,
so quickly that some people may not even realize
an airbag inated. Roof-rail airbags may still be at
least partially inated for some time after they deploy.
Some components of the airbag module may be hot for
several minutes. For location of the airbag modules,
seeWhat Makes an Airbag Inflate? on page 1-59.
The parts of the airbag that come into contact with you
may be warm, but not too hot to touch. There may be
some smoke and dust coming from the vents in the
deated airbags. Airbag ination does not prevent the
driver from seeing out of the windshield or being able to
steer the vehicle, nor does it prevent people from leaving
the vehicle.
{CAUTION:
When an airbag inates, there may be dust
in the air. This dust could cause breathing
problems for people with a history of asthma or
other breathing trouble. To avoid this, everyone
in the vehicle should get out as soon as it is
safe to do so. If you have breathing problems
but cannot get out of the vehicle after an airbag
inates, then get fresh air by opening a window
or a door. If you experience breathing problems
following an airbag deployment, you should
seek medical attention.
Your vehicle has a feature that may automatically
unlock the doors, turn the interior lamps on, and turn
the hazard warning ashers on when the airbags inate.
You can lock the doors, turn the interior lamps off,
and turn the hazard warning ashers off by using the
controls for those features.
1-60

Servicing Your Airbag-Equipped
Vehicle
Airbags affect how your vehicle should be serviced.
There are parts of the airbag system in several places
around your vehicle. Your dealer/retailer and the service
manual have information about servicing your vehicle
and the airbag system. To purchase a service manual,
seeService Publications Ordering Information on
page 7-16.
{CAUTION:
For up to 10 seconds after the ignition is
turned off and the battery is disconnected, an
airbag can still inate during improper service.
You can be injured if you are close to an airbag
when it inates. Avoid yellow connectors. They
are probably part of the airbag system. Be sure
to follow proper service procedures, and make
sure the person performing work for you is
qualied to do so.
Adding Equipment to Your
Airbag-Equipped Vehicle
Q:Is there anything I might add to or change
about the vehicle that could keep the airbags
from working properly?
A:Yes. If you add things that change your vehicle’s
frame, bumper system, height, front end or side
sheet metal, they may keep the airbag system from
working properly. Changing or moving any parts
of the front seats, safety belts, the airbag sensing
and diagnostic module, steering wheel, instrument
panel, roof-rail airbag modules, ceiling headliner
or pillar garnish trim, rearview mirror, front sensors,
rollover sensor module, or airbag wiring can
affect the operation of the airbag system.
In addition, your vehicle has a passenger sensing
system for the right front passenger’s position,
which includes sensors that are part of the
passenger’s seat. The passenger sensing
system may not operate properly if the original
seat trim is replaced with non-GM covers,
upholstery or trim, or with GM covers, upholstery
or trim designed for a different vehicle.
1-66

Any object, such as an aftermarket seat heater or a
comfort enhancing pad or device, installed under or
on top of the seat fabric, could also interfere with
the operation of the passenger sensing system.
This could either prevent proper deployment of the
passenger airbag(s) or prevent the passenger
sensing system from properly turning off the
passenger airbag(s). SeePassenger Sensing
System on page 1-61.
If you have any questions about this, you should
contact Customer Assistance before you modify
your vehicle. The phone numbers and addresses
for Customer Assistance are in Step Two of
the Customer Satisfaction Procedure in this manual.
SeeCustomer Satisfaction Procedure on page 7-2.
If your vehicle has rollover roof-rail airbags, see
Different Size Tires and Wheels on page 5-76
for additional important information.Q:Because I have a disability, I have to get my
vehicle modied. How can I nd out whether
this will affect my airbag system?
A:If you have questions, call Customer Assistance.
The phone numbers and addresses for Customer
Assistance are in Step Two of the Customer
Satisfaction Procedure in this manual. See
Customer Satisfaction Procedure on page 7-2.
In addition, your dealer/retailer and the service manual
have information about the location of the airbag sensors,
sensing and diagnostic module and airbag wiring.
1-67