Page 357 of 600

{CAUTION:
Snow can trap exhaust gases under your
vehicle. This can cause deadly CO (carbon
monoxide) gas to get inside. CO could
overcome you and kill you. You cannot see
it or smell it, so you might not know it is in your
vehicle. Clear away snow from around the base
of your vehicle, especially any that is blocking
your exhaust pipe. And check around again
from time to time to be sure snow does not
collect there.
Open a window just a little on the side of the
vehicle that is away from the wind. This will help
keep CO out.Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps the
battery charged. You will need a well-charged battery to
restart the vehicle, and possibly for signaling later on with
your headlamps. Let the heater run for a while.
Then, shut the engine off and close the window almost all
the way to preserve the heat. Start the engine again and
repeat this only when you feel really uncomfortable from
the cold. But do it as little as possible. Preserve the fuel
as long as you can. To help keep warm, you can get out
of the vehicle and do some fairly vigorous exercises
every half hour or so until help comes.
4-45
Page 405 of 600

If your trailer is equipped with electric brakes, you can
get a jumper harness (electric trailer brake control)
with a trailer battery feed fuse from your dealer.
If you need to tow a light-duty trailer with a standard
four-way round pin connector, you can also get an
adapter form your dealer.
Heavy-DutyTrailer Wiring Harness
Package
For vehicles equipped with heavy duty trailering, the
harness is connected to the trailer plug mounted to the
hitch platform.The eight-wire harness contains the following trailer
circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Light Blue: CHMSL*
Red: Battery Feed**
Dark Blue: Trailer Brake
* The Center High-Mounted Stoplamp (CHMSL) wire
is tied next to the trailer wiring harness for use with
a trailer, slide-in camper or cap.
**If you are charging a remote (non-vehicle) battery,
turn on the headlamps to boost the vehicle system
voltage and properly charge the battery.
4-93
Page 414 of 600

Bulb Replacement..........................................5-63
Halogen Bulbs..............................................5-63
Headlamps..................................................5-63
Front Turn Signal, Sidemarker and
Daytime Running Lamps.............................5-64
Roof Marker Lamps......................................5-66
Center High-Mounted Stoplamp (CHMSL)
and Cargo Lamp........................................5-67
Pickup Box Identi cation and Fender
Marker Lamps...........................................5-68
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-68
Replacement Bulbs.......................................5-70
Windshield Wiper Blade Replacement..............5-71
Tires..............................................................5-72
Tire Sidewall Labeling...................................5-73
Tire Terminology and De nitions.....................5-76
In ation - Tire Pressure.................................5-79
Dual Tire Operation.......................................5-80
Tire Inspection and Rotation...........................5-81
When It Is Time for New Tires.......................5-83
Buying New Tires.........................................5-84
Different Size Tires and Wheels......................5-85Uniform Tire Quality Grading..........................5-86
Wheel Alignment and Tire Balance..................5-87
Wheel Replacement......................................5-87
Tire Chains..................................................5-89
If a Tire Goes Flat........................................5-90
Changing a Flat Tire.....................................5-91
Removing the Spare Tire and Tools................5-92
Removing the Flat Tire and Installing the
Spare Tire................................................5-96
Secondary Latch System..............................5-105
Storing a Flat or Spare Tire and Tools...........5-108
Spare Tire.................................................5-112
Appearance Care..........................................5-113
Cleaning the Inside of Your Vehicle...............5-113
Fabric/Carpet..............................................5-114
Leather......................................................5-115
Instrument Panel, Vinyl, and
Other Plastic Surfaces..............................5-115
Care of Safety Belts....................................5-116
Weatherstrips.............................................5-116
Washing Your Vehicle..................................5-116
Cleaning Exterior Lamps/Lenses....................5-117
Finish Care................................................5-117
Section 5 Service and Appearance Care
5-2
Page 475 of 600
Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 5-70.
For any bulb changing procedure not listed in this
section, contact your dealer.
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.
Headlamps
To replace a headlamp bulb, do the following:
1. Open the hood. SeeHood Release on page 5-13
for more information.
2. Remove the two pins on the top of the headlamp
assembly. To remove the pins, turn the outer pin
outward and pull it straight up. To remove the
inner pin, turn it in and pull it straight up.
5-63
Page 476 of 600
A. Low-Beam Headlamp
B. High-Beam Headlamp
3. Pull the headlamp assembly out.
4. Unplug the electrical connector.
5. Turn the old bulb counterclockwise and remove it
from the headlamp assembly.
6. Install the new bulb into the assembly and turn it
clockwise until it is tight.
7. Plug in the electrical connector.
8. Reinstall the headlamp assembly.
9. Reinstall and tighten the two pins.
Front Turn Signal, Sidemarker and
Daytime Running Lamps
A. Sidemarker Lamp
B. Retainer Clip
C. Front Turn Signal Lamp
D. Daytime Running Lamp (DRL)
5-64
Page 477 of 600
To replace a front turn signal, sidemarker or DRL bulb,
do the following:
1. Open the hood. SeeHood Release on page 5-13
for more information.
2. Remove the headlamp assembly as described
previously. SeeHeadlamps on page 5-63for
more information.
3. Press the retainer clip (B), located behind the turn
signal assembly, towards the outside of the vehicle.4. Pull the turn signal assembly out of the vehicle.
5. Press the locking release lever, turn the bulb socket
counterclockwise and remove it from the turn signal
assembly.
6. Remove the old bulb from the bulb socket.
7. Install a new bulb into the bulb socket.
8. Insert the bulb socket into the turn signal assembly
and turn it clockwise until it locks.
9. Reinstall the turn signal assembly back into the
vehicle placing the hook and posts on the inner side
into the alignment holes rst, then the outer side into
the retainer bracket until you hear a click.
10. Reinstall the headlamp assembly.
5-65
Page 482 of 600
Taillamps (Chassis Cab Models)
A. Turn Signal Lamp
B. Taillamp/Stoplamp
C. Back-up Lamp
To replace one of these bulbs, do the following:
1. Peel the rubber seal away from the lens using
your hands.
2. Lift the lens off the lamp assembly.
3. Pull the old bulb straight out from the socket.
4. Install a new bulb into the socket and press it in
until it is tight.
5. Reinstall the lens and the lens seal.
Replacement Bulbs
Exterior Lamp Bulb Number
Back-up Lamp 3157
Back-up Lamp* 1156
Cargo Lamp and Center
High-Mounted Stoplamp (CHMSL)912
Daytime Running Lamps (DRL) 4114K
Fender Marker, Front Roof Marker
and Sidemarker Lamp (If Equipped)194
Front Parking and Turn Lamp 3457A
Headlamps
High-Beam 9005
Low-Beam 9006
Rear Marker Lamp, Taillamp and
Stoplamp*3157
Rear Turn Signal Lamp 3157
Rear Turn Signal Lamp* 1156
Stoplamp and Taillamp* 1157
* Chassis Cab Models
For replacement bulbs not listed here, contact your
dealer.
5-70
Page 500 of 600

Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted
the same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new GM
original equipment parts. This way, you will be sure to
have the right wheel, wheel bolts and wheel nuts
for your vehicle.
{CAUTION:
Using the wrong replacement wheels, wheel
bolts, or wheel nuts on your vehicle can be
dangerous. It could affect the braking and
handling of your vehicle, make your tires lose
air and make you lose control. You could have
a collision in which you or others could be
injured. Always use the correct wheel, wheel
bolts and wheel nuts for replacement.
Notice:The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance, and tire or tire chain
clearance to the body and chassis.Whenever a wheel, wheel bolt or wheel nut is replaced
on a dual wheel setup, check the wheel nut torque
after 100, 1,000 and 6,000 miles (160, 1 600 and
10 000 km) of driving. For proper torque, see “Wheel
Nut Torque” underCapacities and Speci cations
on page 5-133.
SeeChanging a Flat Tire on page 5-91for more
information.
Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You cannot know how it has been
used or how far it has been driven. It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
5-88