GMC SIERRA 2010 Owner's Manual

The vehicle should:
.Be placed so the headlamps are 25 ft. (7.6 m) from
a light colored wall.
.Have all four tires on a level surface which is level
all the way to the wall.
.Be placed so it is perpendicular to the wall.
.Not have any snow, ice, or mud on it.
.Be fully assembled and all other work stopped
while headlamp aiming is being performed.
.Normally loaded with a full tank of fuel and one
person or 160 lbs (75 kg) sitting on the driver seat.
.Have the tires properly inflated.
.Have the spare tire is in its proper location in the
vehicle.
Headlamp aiming is done with the vehicle's low-beam
headlamps. The high-beam headlamps will be correctly
aimed if the low-beam headlamps are aimed properly. To adjust the vertical aim:
1. Open the hood. See Hood Release on page 6‑15
2. Locate the aim dot on the lens of the low‐beam
headlamp.
3. Record the distance from the ground to the aim dot on the low‐beam headlamp.
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4. At a wall, measure from the ground upward (A) tothe recorded distance from Step 3 and mark it.
5. Draw or tape a horizontal line (B) on the wall the width of the vehicle at the height of the mark
in Step 4.
Notice: Do not cover a headlamp to improve beam
cut-off when aiming. Covering a headlamp may
cause excessive heat build-up which may cause
damage to the headlamp.
6. Turn on the low-beam headlamps and place a piece of cardboard or equivalent in front of the
headlamp not being adjusted. This allows only the
beam of light from the headlamp being adjusted to
be seen on the flat surface.
7. Locate the vertical headlamp aiming screws, whichare under the hood near each headlamp assembly.
The adjustment screw can be turned with an
E8 Torx
®socket.
8. Turn the vertical aiming screw until the headlamp beam is aimed to the horizontal tape line. Turn it
clockwise or counterclockwise to raise or lower
the angle of the beam.
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9. Make sure that the light from the headlamp ispositioned 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 6‑62.
For any bulb changing procedure not listed in this
section, contact your dealer/retailer.
Halogen Bulbs
{WARNING:
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 one of these bulbs:
1. Open the hood. See Hood Release
on page 6‑15for more information.
2. If you are replacing the bulb on the passenger side remove the Engine Air Cleaner cover. See Engine
Air Cleaner/Filter
on page 6‑21for more
information.
3. Reach in and access the bulb sockets from inside the engine compartment.
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4. Turn the bulb socket counterclockwise to remove itfrom 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.
Center High-Mounted Stoplamp
(CHMSL) and Cargo Lamp
To replace one of these bulbs:
1. Remove the screws and lift off the lamp assembly.
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A. Cargo Lamp
B. Center High-Mounted Stoplamp Bulb (CHMSL)
2. Remove the bulbs by turning socket counterclockwise and pulling the bulb straight out.
3. Install the bulbs by pushing the bulb straight in and turning clockwise.
4. Reinstall the lamp assembly and tighten the screws.
Pickup Box Identification and
Fender Marker Lamps
To replace a pickup box identification 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.
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Taillamps, Turn Signal, Stoplamps
and Back-up Lamps
To replace one of these bulbs:1. Open the tailgate. Tailgate
on page 3‑12for
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.
Dual Tire Models
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.
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All Other Models
A. Stoplamp/Taillamp/Turn Signal Lamp
B. Stoplamp/Taillamp/Turn Signal Lamp
C. 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.
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.
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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.
Replacement Bulbs
Exterior Lamp Bulb Number
Back-up Lamp 3047 or 921
Back-up Lamp* 1156
Cargo Lamp and Center
High-Mounted Stoplamp (CHMSL) 912
Fender Marker W5WLL
High-Beam Headlamp 9005
Low-Beam Headlamp H11
License Plate Lamp 168
Stoplamp/Taillamp/Turn Signal Lamp 3047
Sidemarker Lamp 194
Stoplamp/Turn Signal Lamp/Taillamp* 1157
* Chassis Cab Models
For replacement bulbs not listed here, contact your
dealer/retailer.
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Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for wear
or cracking. SeeScheduled Maintenanceon page 7‑3for more information on wiper blade inspection.
Replacement blades come in different types and are
removed in different ways. Here is how to remove the
wiper blade:
1. Pull the windshield wiper arm connector away from the windshield.
2. Squeeze the grooved areas on each side of theblade and turn the blade assembly away from the
arm connector.
3. Install the new blade onto the arm connector and
make sure the grooved areas are fully set in the
locked position.
For the proper type and size, see Maintenance
Replacement Parts on page 7‑15.
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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 vehicle
Warranty booklet for details. For additional
information refer to the tire manufacturer.
{CAUTION:
Poorly maintained and improperly used tires
are dangerous.
.Overloading your vehicle's tires can
cause overheating as a result of too
much flexing. You could have an air-out
and a serious accident. SeeLoading the
Vehicle
on page 5‑30.
.Underinflated tires pose the same danger
as overloaded tires. The resulting
accident could cause serious injury.
Check all tires frequently to maintain the
recommended pressure. Tire pressure
(Continued)
CAUTION: (Continued)
should be checked when your vehicle's
tires are cold. See Inflation - Tire
Pressure
on page 6‑72.
.Overinflated 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.
20‐Inch Tires
If your vehicle has the optional 20‐inch
P275/55R20 size tires, they are classified as
touring tires and are designed for on road use.
The low‐profile, wide tread design is not
recommended for “off‐road”driving or commercial
uses such as snow plowing. See Off-Road Driving
on page 5‑11andAdding a Snow Plow or Similar
Equipment
on page 5‑36for additional information.
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