GMC YUKON 2008 Owner's Manual

To get an accurate reading, the vehicle should be on a
level surface.
For all 4.8L and 5.3L 1500 Series applications, the
proper level is from 0.04 inch to 0.75 inch (1.0 mm
to 19.0 mm) below the bottom of the ller plug
hole, located on the rear axle. Add only enough uid
to reach the proper level.
For all 6.0L 1500 Series applications, the proper
level is from 0.6 inch to 1.6 inches (15 mm to
40 mm) below the bottom of the ller plug hole,
located on the rear axle. Add only enough uid to
reach the proper level.
The proper ll level for the 2500 Series is from 0 to
1/2 inch (0 to 13 mm) below the bottom of the ller
plug hole, located at the front of the axle. Add
only enough uid to reach the proper level.
2500 Series
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Four-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. There are two additional systems that need
lubrication.
Transfer Case
When to Check Lubricant
It is not necessary to regularly check transfer case uid
unless you suspect there is a leak, or you hear an
unusual noise. A uid loss could indicate a problem.
Have it inspected and repaired.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
If the level is below the bottom of the ller plug hole,
you will need to add some lubricant. Add enough
lubricant to raise the level to the bottom of the ller plug
hole. Use care not to overtighten the plug.Automatic Transfer Case
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When to Change Lubricant
Refer to the Maintenance Schedule to determine how
often to change the lubricant. SeeScheduled
Maintenance on page 6-4.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeeRecommended Fluids
and Lubricants on page 6-13.
Front Axle
When to Check and Change Lubricant
It is not necessary to regularly check front axle uid
unless you suspect there is a leak or you hear an
unusual noise. A uid loss could indicate a problem.
Have it inspected and repaired.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
A:Fill Plug
B:Drain Plug1500 Series
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A:Fill Plug
B:Drain Plug
If the level is below the bottom of the ller plug hole,
located on the front axle, you may need to add
some lubricant:
When the differential is cold, add enough lubricant
to raise the level from 0 (0 mm) to 1/8 inch
(3.2 mm) below the ller plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level
to the bottom of the ller plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeeRecommended Fluids
and Lubricants on page 6-13.
Headlamp Aiming
The vehicle has a visual optical headlamp aiming
system. The aim of the headlamps have been preset at
the factory and should need no further adjustment.
However, if the vehicle is damaged in a crash, the aim
of the headlamps may be affected and adjustment
may be necessary.
If oncoming vehicles ash their high beams at you, this
may mean the vertical aim of your headlamps needs
to be adjusted.
It is recommended that the vehicle is taken to your
dealer/retailer for service if the headlamps need to be
adjusted. It is possible however, to re-aim the
headlamps as described. 2500 Series
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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 inated.
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. SeeHood Release on page 5-13
for more information.
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) to
the 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 at surface.7. Locate the vertical headlamp aiming screws, which
are under the hood near each headlamp assembly.
The adjustment screw can be turned with a 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 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 5-61.
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.
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Taillamps, Turn Signal, Stoplamps
and Back-up Lamps
A. Taillamp/
Turn Signal Lamp
B. Back-up Lamp
C. Stoplamp/Taillamp
If your vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
To replace one of these bulbs:
1. Open the liftgate. SeePower Liftgate on page 2-15
for more information.2. Remove the two
screws from the
taillamp assembly.
3. Pull the taillamp assembly rearward until you
disengage the inner pins on the taillamp assembly
from the vehicle.
4. Press the release tab, if bulb socket has one, and
turn the bulb socket counterclockwise to remove it
from the taillamp assembly.
5. Pull the old bulb straight out from the bulb socket.
6. Press a new bulb into the bulb socket and insert
it into the taillamp assembly. Turn the bulb socket
clockwise into the taillamp assembly until it clicks.
7. Reinstall the taillamp assembly. When reinstalling,
make sure to line up the pins on the taillamp
assembly with the vehicle. If you do not do this, you
will not be able correctly install the taillamp
assembly.
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License Plate Lamp
1. Remove the two screws holding each of the license
plate lamps to the molding that is part of the
liftgate.
2. Twist and pull the license plate lamp forward
through the molding opening.3. Turn the bulb socket counterclockwise and pull the
bulb straight out of the socket.
4. Install the new bulb.
5. Reverse Steps 1 through 3 to reinstall the license
plate lamp.
Replacement Bulbs
Exterior Lamp Bulb Number
Back-up Lamp 7441
License Plate Lamp 168
Rear Turn Signal Lamp, Taillamp,
and Stoplamp3057KX
For replacement bulbs not listed here, contact your
dealer/retailer.
If your vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
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Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for wear
or cracking. SeeScheduled Maintenance on page 6-4.
Replacement blades come in different types and
are removed in different ways. To replace the wiper
blade assembly:
1. Pull the windshield wiper arm connector away from
the windshield.
2. Squeeze the grooved areas on each side of the
blade, 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, seeMaintenance
Replacement Parts on page 6-15.
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