2008 GMC SIERRA belt

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

{CAUTION:
Sitting in a reclined position when your vehicle
is in motion can be dangerous. Even if you
buckle up, your safety belts cannot do their
job when you are reclined like this.
The shoulder belt cannot do its job. In a crash,
you could go into it, receiving neck or other
injuries.
The lap belt cannot do its job either. In a crash
the belt could go up over your abdomen. The
belt forces would be there, not at your pelvic
bones. This could cause serious internal
injuries.
For proper protection when the vehicle is in
motion, have the seatback upright. Then sit
well back in the seat and wear your safety belt
properly.
On seats with manual reclining seatbacks, the lever
used to operate them is located on the outboard side of
the seat(s).To recline the seatback:
1. Lift the recline lever.
2. Move the seatback to the desired position, then
release the lever to lock the seatback in place.
3. Push and pull on the seatback to make sure it is
locked.
To return the seatback to an upright position, do the
following:
1. Lift the lever fully without applying pressure to the
seatback and the seatback will return to the upright
position.
2. Push and pull on the seatback to make sure it is
locked.
1-9

Center Seat
Your vehicle may have a front center seat. The seatback
doubles as an armrest and cupholder/storage area for
the driver and passenger when the center seat is
not used. Do not use it as a seating position when the
seatback is folded down.
Rear Seats
Rear Seat Operation (Full Bench)
Folding the Rear Seat
To fold the seat up, do the following:
Notice:Folding a rear seat with the safety belts
still fastened may cause damage to the seat or the
safety belts. Always unbuckle the safety belts
and return them to their normal stowed position
before folding a rear seat.1. Pull up on the front of
the seat cushion while
pulling down on the
release strap, located
under the seat
cushion.
2. Pull the seat cushion up until it latches with the
seatback.
3. After latching the seat cushion up, pull forward on it
to make sure it is locked.
To fold the seat down, do the following:
1. Push the seat cushion rearward while pulling the
release strap, located under the seat cushion. Pull
the seat cushion down until it latches.
2. After latching the seat cushion, pull up on it to
make sure it is locked.
1-12

Rear Seat Operation (Split Bench)
Folding Rear Seat
On a vehicle with a second row 60/40 split seat
either side of the rear seat may be folded for added
cargo space.
Notice:Folding a rear seat with the safety belts
still fastened may cause damage to the seat or the
safety belts. Always unbuckle the safety belts
and return them to their normal stowed position
before folding a rear seat.
Make sure that nothing is on the seat.
To fold the seat, slowly pull the seat cushion up.
To return the seat to the normal seating position, slowly
pull the seat cushion down.
{CAUTION:
A safety belt that is improperly routed, not
properly attached, or twisted will not provide
the protection needed in a crash. The person
wearing the belt could be seriously injured.
After raising the rear seatback, always check
to be sure that the safety belts are properly
routed and attached, and are not twisted.
1-13

Safety Belts
Safety Belts: They Are for Everyone
This part of the manual tells you how to use safety
belts properly. It also tells you some things you should
not do with safety belts.
{CAUTION:
Do not let anyone ride where he or she cannot
wear a safety belt properly. If you are in a
crash and you are not wearing a safety belt,
your injuries can be much worse. You can hit
things inside the vehicle harder or be ejected
from it and be seriously injured or killed. In the
same crash, you might not be, if you are
buckled up. Always fasten your safety belt,
and check that your passenger(s) are
restrained properly too.
{CAUTION:
People riding on the tailgate (if equipped) can
easily lose their balance and fall even when
the vehicle is operated at low speeds. Falling
from a moving vehicle may result in serious
injuries or death.
{CAUTION:
It is extremely dangerous to ride in a cargo
area, inside or outside of a vehicle. In a
collision, people riding in these areas are more
likely to be seriously injured or killed. Do not
allow people to ride in any area of your vehicle
that is not equipped with seats and safety
belts. Be sure everyone in your vehicle is in a
seat and using a safety belt properly.
Your vehicle has indicators as a reminder to buckle your
safety belts. SeeSafety Belt Reminders on page 3-37.
1-14

In most states and in all Canadian provinces, the law
requires wearing safety belts. Here is why:
You never know if you will be in a crash. If you do have
a crash, you do not know if it will be a serious one.
A few crashes are mild, and some crashes can be so
serious that even buckled up, a person would not
survive. But most crashes are in between. In many of
them, people who buckle up can survive and sometimes
walk away. Without belts they could have been badly
hurt or killed.
After more than 40 years of safety belts in vehicles, the
facts are clear. In most crashes buckling up does
matter... a lot!Why Safety Belts Work
When you ride in or on anything, you go as fast as
it goes.
Take the simplest vehicle. Suppose it is just a seat on
wheels.
1-15

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