2007 GMC SIERRA CLASSIC Owners Manual

Center High-Mounted Stoplamp
(CHMSL) and Cargo Lamp
To replace one of these bulbs, do the following:
1. Remove the screws and lift off the lamp
assembly.A. Cargo Lamp
B. Center High-Mounted Stoplamp Bulb
2. Remove the back plate from the assembly by
pressing the release tabs.
3. Remove the CHMSL bulb by pulling the bulb
straight out from the holder back plate.
Remove a cargo bulb by turning the socket
counterclockwise and pulling the bulb
straight out.
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4. If a CHMSL bulb is replaced, put the new bulb
into the socket and press it in until it is tight.
If a cargo lamp is replaced, put a new
cargo lamp bulb into the socket and press
it in until it is tight before turning the socket
counterclockwise.
5. Reinstall the back plate into the lamp
assembly.
6. Reinstall the lamp assembly and tighten
the screws.Pickup Box Identication and
Fender Marker Lamps
To replace a pickup box identication or fender
marker lamp bulb, do the following:
1. Remove the screws and lamp assembly.
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.
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Taillamps, Turn Signal, Stoplamps
and Back-up Lamps
To replace one of these bulbs, do the following:
1. Open the tailgate.Tailgate on page 127
for more information.
2. Remove the two
rear lamp assembly
screws near the
tailgate latch
and pull out the
lamp assembly.
3. Determine which of the following taillamp
assembly applies to your vehicle.4. Press the release tab, if the vehicle has one,
and turn the bulb socket counterclockwise to
remove it from the taillamp assembly.
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.
A. Stoplamp/Taillamp
B. Turn Signal
C. Back-up Lamp
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A. Stoplamp/Taillamp
B. Turn Signal Lamp
C. Back-up Lamp
D. Sidemarker LampTaillamps (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.
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.
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License Plate Lamp
To replace one of these bulbs, do the following:
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.
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 Lamp (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
License Plate Lamp 168
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.
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Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for
wear and cracking. SeeScheduled Maintenance
(Gasoline Engine) on page 617for more
information.
Replacement blades come in different types and
are removed in different ways. For proper type and
length, seeNormal Maintenance Replacement
Parts (Gasoline Engines) on page 632.To replace the windshield wiper blade assembly
do the following:
1. Lift the wiper arm away from the windshield.
2. Push the release lever (B) to disengage the
hook and push the wiper arm (A) out of the
blade (C).
3. Push the new wiper blade securely on the
wiper arm until you hear the release lever
click into place.
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Tires
Your new vehicle comes with high-quality tires
made by a leading tire manufacturer. If you ever
have questions about your tire warranty and where
to obtain service, see your GM Warranty booklet
for details. For additional information refer to
the tire manufacturer’s booklet included with your
vehicle.
{CAUTION:
Poorly maintained and improperly used
tires are dangerous.
Overloading your vehicle’s tires can
cause overheating as a result of too
much friction. You could have an
air-out and a serious accident. See
Loading Your Vehicle on page 409.
CAUTION: (Continued)
CAUTION: (Continued)

Underinated tires pose the
samedanger as overloaded tires. The
resulting accident could cause serious
injury. Check all tires frequently to
maintain the recommended pressure.
Tire pressure should be checked when
your vehicle’s tires are cold. See
Inflation - Tire Pressure on page 551.
Overinated tires are more likely
to be cut, punctured, or broken by a
sudden impact — such as when
you hit a pothole. Keep tires at the
recommended pressure.
Worn, old tires can cause accidents.
If the tire’s tread is badly worn, or
if your vehicle’s tires have been
damaged, replace them.
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20-Inch Tires
If your vehicle has the optional 20-inch
P275/55R20 size tires, they are classied as
touring tires and are designed for on road use. The
low-prole, wide tread design is not recommended
for “off-road” driving or commercial uses such
as snow plowing. SeeOff-Road Driving on
page 372andAdding a Snow Plow or Similar
Equipment on page 416for additional information.
Tire Sidewall Labeling
Useful information about a tire is molded into the
sidewall. The following illustrations are examples
of a typical P-Metric and a LT-Metric tire sidewall.
(A) Tire Size:The tire size code is a combination
of letters and numbers used to dene a particular
tire’s width, height, aspect ratio, construction
type, and service description. See the “Tire Size”
illustration later in this section for more detail.
Passenger (P-Metric) Tire
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