2004 GMC YUKON Owner's Manual

Four-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. However, 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 noice. A uid loss could indicate a problem.
Have it inspeced 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’ll 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.
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 6-12.
Automatic Transfer Case
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Front Axle
When to Check 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.
If the level is below the bottom of the ller plug hole,
you may need to add some lubricant.
When the differential is cold, add enough lubricant to
raise the level to 0 to 3/8 inch (9.5 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
To determine what kind of lubricant to use, see
Recommended Fluids and Lubricants on page 6-12.
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Bulb Replacement
For any bulb changing procedure not listed in this
section, contact your dealer.
SeeReplacement Bulbs on page 5-61for the proper
types of bulbs to use.
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
1. Your vehicle is equipped with two pins, 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.
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A. Low-Beam Headlamp
B. High-Beam Headlamp
2. Pull the headlamp assembly out.
3. Unplug the electrical connector.
4. Turn the old bulb counterclockwise and remove it
from the headlamp assembly.
5. Put the new bulb into the assembly and turn it
clockwise until it is tight. Use care not to touch
the bulb with your ngers or hands.
6. Plug in the electrical connector.
7. Put the headlamp assembly back into the vehicle.
Install and tighten the two pins.
Front Turn Signal, Sidemarker and
Daytime Running Lamps
A. Sidemarker Lamp
B. Retainer Clip
C. Front Turn Signal
LampD. Daytime Running
Lamp
1. Remove the headlamp assembly as mentioned
previously.
2. Press the retainer clip, located behind the turn
signal housing, towards the outside of the vehicle.
3. Pull the turn signal housing out from the vehicle.
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4. Press the locking release lever, turn the bulb socket
counterclockwise and remove the socket from the
turn signal housing.
5. Remove the old bulb from the bulb socket.
6. Put the new bulb into the bulb socket. Use care not
to touch the bulb with your ngers or hands.
7. Put the bulb socket into the turn signal housing and
turn it clockwise until it locks.
8. Reinstall the turn signal housing onto the vehicle,
placing the hook and posts on the inner side into
the alignment holes, and the outer side into
the retainer bracket. Push until you hear a click.
9. Reinstall the headlamp assembly.Side Identication Marker Lamps
1. To expose the service slot, locate the lamp gasket
near the rear wheel, and pull back the edge.
2. Using a at tool, push into the slot to release the
lamp housing.
3. Pull the housing out to expose the wiring harness
and connector.
4. Unplug the lamp assembly harness from the
housing.
5. Unplug the lamp.
6. Put in a new lamp and snap it into the housing.
7. Reinstall the lamp housing.
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Roof Marker Lamps
1. Remove the two
screws and lift off
the lens.
2. Remove the six screws on the center roof marker
lamps.
3. Turn the old bulb counterclockwise to remove it
from the socket.
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4. Put a new bulb into the
socket and turn
clockwise until it locks
in place.
5. Reinstall the lens and tighten the screws.
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Taillamps
A. Turn Signal Lamp
B. Back-up Lamp
C. Stoplamp1. Use a tool to remove
the two screws from
the lamp assembly.
2. Remove the lamp assembly.
3. Press the release tab and turn the bulb socket
counterclockwise to remove it from the taillamp
housing.
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