bulb GMC SIERRA 2008 Owner's Manual

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

Turn and Lane-Change Signals
The turn signal has two upward (for right) and two
downward (for left) positions. These positions allow
you to signal a turn or a lane change.
To signal a turn, move the lever all the way up or down.
When the turn is nished, the lever will return
automatically.
To signal a lane change, raise or lower the lever for
less than one second until the arrow starts to ash.
This will cause the turn signals to automatically
ash three times. It will ash six times if tow-haul mode
is active. Holding the turn signal lever for more than
one second will cause the turn signals to ash until you
release the lever. The lever will return by itself when
it is released.An arrow on the instrument
panel cluster will ash in
the direction of the
turn or lane change.
As you signal a turn or a lane change, if the arrows
ash more quickly than normal, a signal bulb may
be burned out and other drivers will not see your
turn signal.
If a bulb is burned out, replace it to help avoid an
accident. If the arrows do not go on at all when you
signal a turn, check for burned-out bulbs and a blown
fuse. SeeFuses and Circuit Breakers on page 5-123.
3-10

Turn Signals When Towing a Trailer
The arrows on your instrument panel will ash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will also ash, telling other drivers
you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will ash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It’s
important to check occasionally to be sure the trailer
bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don’t shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.You can tow in DRIVE (D). You may want to shift the
transmission to lower gear selection if the transmission
shifts too often (e.g., under heavy loads and/or hilly
conditions).
You may also want to activate the tow/haul mode if the
transmission shifts too often. SeeTow/Haul Mode
Light on page 3-53.
When towing at high elevation on steep uphill grades,
consider the following: Engine coolant at higher
elevations will boil at a lower temperature than at or
near sea level. If you turn your engine off immediately
after towing at high elevation on steep uphill grades,
your vehicle may show signs similar to engine
overheating. To avoid this, let the engine run while
parked, preferably on level ground, with the transmission
in PARK (P) at least ve minutes before turning the
engine off. If you do get the overheat warning, see
Engine Overheating on page 5-30.
4-88

Headlamp Aiming...........................................5-56
Bulb Replacement..........................................5-59
Halogen Bulbs..............................................5-59
Headlamps..................................................5-60
Center High-Mounted Stoplamp (CHMSL) and
Cargo Lamp.............................................5-61
Pickup Box Identication and Fender
Marker Lamps...........................................5-62
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-62
License Plate Lamp......................................5-64
Replacement Bulbs.......................................5-65
Windshield Wiper Blade Replacement..............5-65
Tires..............................................................5-66
Tire Sidewall Labeling...................................5-67
Tire Terminology and Denitions.....................5-71
Ination - Tire Pressure.................................5-74
Dual Tire Operation.......................................5-76
Tire Pressure Monitor System.........................5-76
Tire Pressure Monitor Operation.....................5-78
Tire Inspection and Rotation...........................5-81
When It Is Time for New Tires.......................5-84
Buying New Tires.........................................5-84Different Size Tires and Wheels......................5-86
Uniform Tire Quality Grading..........................5-86
Wheel Alignment and Tire Balance..................5-88
Wheel Replacement......................................5-88
Tire Chains..................................................5-90
If a Tire Goes Flat........................................5-91
Changing a Flat Tire.....................................5-92
Removing the Spare Tire and Tools................5-93
Removing the Flat Tire and Installing the
Spare Tire................................................5-98
Secondary Latch System..............................5-105
Storing a Flat or Spare Tire and Tools...........5-108
Spare Tire.................................................5-112
Appearance Care
..........................................5-112
Interior Cleaning.........................................5-112
Fabric/Carpet..............................................5-114
Leather......................................................5-114
Instrument Panel, Vinyl, and Other Plastic
Surfaces.................................................5-115
Care of Safety Belts....................................5-115
Weatherstrips.............................................5-115
Washing Your Vehicle..................................5-116
Cleaning Exterior Lamps/Lenses....................5-116
Finish Care................................................5-116
Section 5 Service and Appearance Care
5-2

9. Make sure that the light from the headlamp is
positioned at the bottom edge of the horizontal tape
line. The lamp on the left (A) shows the correct
headlamp aim. The lamp on the right (B) shows the
incorrect headlamp aim.
10. Repeat Steps 7 through 9 for the opposite
headlamp.
Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 5-65.
For any bulb changing procedure not listed in this
section, contact your dealer/retailer.
Halogen Bulbs
{CAUTION:
Halogen bulbs have pressurized gas inside
and can burst if you drop or scratch the bulb.
You or others could be injured. Be sure to read
and follow the instructions on the bulb
package.
5-59

Headlamps
To replace one of these bulbs:
1. Open the hood. SeeHood Release on page 5-13
for more information.
2. If you are replacing the bulb on the passenger side
remove the Engine Air Cleaner cover. SeeEngine
Air Cleaner/Filter (Gasoline Engines) on page 5-19
for more information.
3. Reach in and access the bulb sockets from inside
the engine compartment.
4. Turn the bulb socket counterclockwise to remove it
from the headlamp assembly and pull it straight out.
5. Unplug the electrical connector from the old bulb by
releasing the clips on the bulb socket.
6. Replace it with a new bulb socket.
7. Plug in the electrical connector to the new
bulb socket.
8. Reinstall the new bulb socket into the headlamp
assembly and turn it clockwise to secure.
9. Close the hood.
5-60

Center High-Mounted Stoplamp
(CHMSL) and Cargo Lamp
To replace one of these bulbs:
1. Remove the screws and lift off the lamp assembly.A. Cargo Lamp
B. Center High-Mounted Stoplamp Bulb (CHMSL)
2. Remove the CHMSL and Cargo bulbs by turning
socket counterclockwise and pulling the bulb
straight out.
3. Install the CHMSL and Cargo bulbs by pushing the
bulb straight in and turning clockwise.
4. Reinstall the lamp assembly and tighten the screws.
5-61

Pickup Box Identication and
Fender Marker Lamps
To replace a pickup box identication or fender marker
lamp bulb:
1. Press the tab from the back to remove the lamp.
2. Unplug the lamp assembly harness.
3. Gently pry the individual lamp from the lamp
assembly.
4. Unplug the lamp.
5. Plug in a new lamp and snap it into the assembly.
6. Reinstall the lamp assembly.
Taillamps, Turn Signal, Stoplamps
and Back-up Lamps
To replace one of these bulbs:
1. Open the tailgate.Tailgate on page 2-14for more
information.
2. Remove the two rear
lamp assembly screws
near the tailgate latch
strikerpost and pull out
the lamp assembly.
3. Determine which of the following taillamp
assemblies applies to your vehicle.
5-62

A. Stoplamp/Taillamp/Turn Signal Lamp
B. Back-up Lamp
C. Stoplamp/Taillamp/Turn Signal Lamp
4. Press the tab, if the vehicle has one, and turn the
bulb socket counterclockwise to remove it from the
taillamp assembly.A. Stoplamp/Taillamp/Turn
Signal Lamp
B. Stoplamp/Taillamp/Turn
Signal LampC. Back-up Lamp
D. Sidemarker Lamp
5. Pull the old bulb straight out from the socket.
6. Press a new bulb into the socket and turn the socket
clockwise into the taillamp assembly.
7. Reinstall the taillamp assembly. Dually Models
All Other Models
5-63

Taillamps (Chassis Cab Models)
A. Backup Lamp
B. Stoplamp/Taillamp/Turn Signal Lamp
To replace one of these bulbs:
1. Remove the four screws.
2. Lift the lens off the lamp assembly.
3. Turn the old bulb counterclockwise and pull the it
straight out from the socket.
4. Install a new bulb into the socket, turn it clockwise,
and press it in until it is tight.
5. Reinstall the lens and the four screws.
License Plate Lamp
To replace one of these bulbs:
1. Reach under the rear bumper for the bulb socket.
2. Turn the bulb socket counterclockwise and pull the
bulb socket out of the connector.
3. Pull the old bulb from the bulb socket, keeping the
bulb straight as you pull it out.
4. Install the new bulb.
5. Reverse Steps 1 through 3 to reinstall the
bulb socket.
5-64