2008 GMC SIERRA airbag

Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-3
Rear Seats
..............................................1-12
Safety Belts
.............................................1-14
Child Restraints
.......................................1-35
Airbag System
.........................................1-68
Restraint System Check
............................1-87
Features and Controls..................................... 2-1
Keys
........................................................ 2-3
Doors and Locks
......................................2-10
Windows
.................................................2-15
Theft-Deterrent Systems
............................2-18
Starting and Operating Your Vehicle
...........2-22
Mirrors
....................................................2-55
Object Detection Systems
..........................2-63
OnStar
®System
......................................2-65
Universal Home Remote System
................2-68
Storage Areas
.........................................2-74
Sunroof
..................................................2-79
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-4
Climate Controls
......................................3-25
Warning Lights, Gages, and Indicators
........3-34
Driver Information Center (DIC)
..................3-54
Audio System(s)
.......................................3-80Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-50
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-4
Fuel
......................................................... 5-6
Checking Things Under the Hood
...............5-12
Rear Axle
...............................................5-51
Four-Wheel Drive
.....................................5-52
Front Axle
...............................................5-54
Noise Control System
...............................5-56
Headlamp Aiming
.....................................5-56
Bulb Replacement
....................................5-59
Windshield Wiper Blade Replacement
.........5-65
Tires
......................................................5-66
Appearance Care
...................................5-112
Vehicle Identication
...............................5-121
Electrical System
....................................5-122
Capacities and Specications
...................5-130
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance Information.................... 7-1
Customer Assistance and Information
........... 7-2
Reporting Safety Defects
...........................7-14
Vehicle Data Recording and Privacy
...........7-16
Index................................................................ 1
2008 GMC Sierra Owner ManualM

Front Seats......................................................1-3
Manual Seats................................................1-3
Power Seats..................................................1-4
Manual Lumbar..............................................1-5
Power Lumbar...............................................1-5
Heated Seats.................................................1-6
Memory Seat, Mirrors, and Pedals....................1-6
Reclining Seatbacks........................................1-8
Head Restraints............................................1-10
Seatback Latches.........................................1-11
Center Seat.................................................1-12
Rear Seats.....................................................1-12
Rear Seat Operation (Full Bench)...................1-12
Rear Seat Operation (Split Bench)..................1-13
Safety Belts...................................................1-14
Safety Belts: They Are for Everyone................1-14
How to Wear Safety Belts Properly.................1-19
Lap-Shoulder Belt.........................................1-28
Safety Belt Use During Pregnancy..................1-33
Lap Belt (Crew and Extended Cab).................1-34
Safety Belt Extender.....................................1-35Child Restraints.............................................1-35
Older Children..............................................1-35
Infants and Young Children............................1-38
Child Restraint Systems.................................1-42
Where to Put the Restraint.............................1-44
Lower Anchors and Tethers for Children
(LATCH)..................................................1-45
Securing a Child Restraint in a Rear Seat
Position...................................................1-55
Securing a Child Restraint in the Center Front
Seat Position............................................1-57
Securing a Child Restraint in the Right Front
Seat Position (With Airbag Off Switch)..........1-58
Securing a Child Restraint in the Right Front
Seat Position (With Passenger Sensing
System)...................................................1-62
Securing a Child Restraint in the Right
Front Seat Position (Heavy Duty Crew
Cab Only)...............................................
.1-66
Section 1 Seats and Restraint Systems
1-1

Airbag System...............................................1-68
Where Are the Airbags?................................1-71
When Should an Airbag Inate?.....................1-73
What Makes an Airbag Inate?.......................1-74
How Does an Airbag Restrain?.......................1-74
What Will You See After an Airbag Inates?.....1-75
Airbag Off Switch..........................................1-76Passenger Sensing System............................1-80
Servicing Your Airbag-Equipped Vehicle...........1-84
Adding Equipment to Your Airbag-Equipped
Vehicle....................................................1-85
Restraint System Check..................................1-87
Checking the Restraint Systems......................1-87
Replacing Restraint System Parts After
a Crash...................................................1-88
Section 1 Seats and Restraint Systems
1-2

or the safety belts!
With safety belts, you slow down as the vehicle does.
You get more time to stop. You stop over more distance,
and your strongest bones take the forces. That is why
safety belts make such good sense.
Questions and Answers About
Safety Belts
Q:Will I be trapped in the vehicle after a crash if I
am wearing a safety belt?
A:Youcouldbe — whether you are wearing a safety
belt or not. But your chance of being conscious
during and after an accident, so you can unbuckle
and get out, ismuchgreater if you are belted.
And you can unbuckle a safety belt, even if you are
upside down.
Q:If my vehicle has airbags, why should I have to
wear safety belts?
A:Airbags are supplemental systems only; so they
workwithsafety belts — not instead of them.
Whether or not an airbag is provided, all occupants
still have to buckle up to get the most protection.
That is true not only in frontal collisions, but
especially in side and other collisions.
1-18

Safety Belt Pretensioners
Your vehicle has safety belt pretensioners for front
outboard occupants. Although you cannot see them,
they are part of the safety belt assembly. They can help
tighten the safety belts during the early stages of a
moderate to severe frontal, near frontal, or rear crash if
the threshold conditions for pretensioner activation
are met. And, if your vehicle has side impact airbags,
safety belt pretensioners can help tighten the safety
belts in a side crash or a rollover event.
Pretensioners work only once. If they activate in a
crash, you will need to get new ones, and probably other
new parts for your safety belt system. SeeReplacing
Restraint System Parts After a Crash on page 1-88.
Rear Safety Belt Comfort Guides
Rear shoulder belt comfort guides may provide added
safety belt comfort for older children who have outgrown
booster seats and for some adults. When installed on
a shoulder belt, the comfort guide positions the belt
away from the neck and head.There is one guide for each outboard passenger
position in the rear seat. Here is how to install a comfort
guide to the shoulder belt:
1. Remove the guide from its storage clip on the
interior body.
2. Place the guide over the belt and insert the two
edges of the belt into the slots of the guide.
1-31

{CAUTION:
Children who are up against, or very close to,
any airbag when it inates can be seriously
injured or killed. Airbags plus lap-shoulder
belts offer protection for adults and older
children, 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.
Q:What are the different types of add-on child
restraints?
A:Add-on child restraints, which are purchased by the
vehicle’s owner, are available in four basic types.
Selection of a particular restraint should take
into consideration not only the child’s weight, height,
and age but also whether or not the restraint will
be compatible with the motor vehicle in which it will
be used.
For most basic types of child restraints, there are
many different models available. When purchasing a
child restraint, be sure it is designed to be used
in a motor vehicle. If it is, the restraint will have a
label saying that it meets federal motor vehicle
safety standards.
The restraint manufacturer’s instructions that come
with the restraint state the weight and height
limitations for a particular child restraint. In addition,
there are many kinds of restraints available for
children with special needs.
1-40

Where to Put the Restraint
Accident statistics show that children are safer if they
are restrained in the rear rather than the front seat.
We recommend that children and child restraints
be secured in a rear seat, including: an infant or a child
riding in a rear-facing child restraint; a child riding in
a forward-facing child seat; an older child riding in
a booster seat; and children, who are large enough,
using safety belts.
A label on your sun visor says, “Never put a rear-facing
child seat in the front.” This is because the risk to the
rear-facing child is so great, if the airbag deploys.
{CAUTION:
A child in a rear-facing child restraint can be
seriously injured or killed if the right front
passenger’s airbag inates. This is because
the back of the rear-facing child restraint
would be very close to the inating airbag.
CAUTION: (Continued)
CAUTION: (Continued)
Even though the passenger sensing system or
the airbag off switch is designed to turn off the
right front passenger’s frontal airbag if the
system detects a rear-facing child restraint, no
system is fail-safe, and no one can guarantee
that an airbag will not deploy under some
unusual circumstance, even though it is turned
off. We recommend that rear-facing child
restraints be secured in a rear seat, even if the
airbag is off.
If you secure a forward-facing child restraint in
the right front seat, always move the front
passenger seat as far back as it will go. It is
better to secure the child restraint in a rear seat.
1-44

{CAUTION:
A child in a child restraint in the center front
seat can be badly injured or killed by the
frontal airbags if they inate. Never secure a
child restraint in the center front seat. It is
always better to secure a child restraint in a
rear seat.
Do not use child restraints in the center front seat
position.
When securing a child restraint in a rear seating
position, study the instructions that came with your child
restraint to make sure it is compatible with this vehicle.
If your vehicle does not have a rear seat that will
accommodate a rear-facing child restraint, we
recommend that rear-facing child restraints not be
transported in your vehicle, even if the airbag is off.
Wherever you install a child restraint, be sure to secure
the child restraint properly.
Keep in mind that an unsecured child restraint can
move around in a collision or sudden stop and injure
people in the vehicle. Be sure to properly secure
any child restraint in your vehicle — even when no
child is in it.
Lower Anchors and Tethers for
Children (LATCH)
The LATCH system holds a child restraint during driving
or in a crash. This system is designed to make
installation of a child restraint easier. The LATCH
system uses anchors in the vehicle and attachments on
the child restraint that are made for use with the
LATCH system.
Make sure that a LATCH-compatible child restraint is
properly installed using the anchors, or use the vehicle’s
safety belts to secure the restraint, following the
instructions that came with that restraint, and also the
instructions in this manual. When installing a child
restraint with a top tether, you must also use either the
lower anchors or the safety belts to properly secure
the child restraint. A child restraint must never be
installed using only the top tether and anchor.
In order to use the LATCH system in your vehicle, you
need a child restraint that has LATCH attachments.
The child restraint manufacturer will provide you
with instructions on how to use the child restraint and its
attachments. The following explains how to attach a
child restraint with these attachments in your vehicle.
Not all vehicle seating positions or child restraints have
lower anchors and attachments or top tether anchors
and attachments.
1-45