GMC YUKON XL 2006 Owners Manual

Also, if a vehicle has just been driven before checking the
uid level, it may appear lower than normal because uid
has traveled out along the axle tubes and has not drained
back to the sump area. Therefore, a reading taken
ve minutes after the vehicle has been driven will appear
to have a lower uid level than a vehicle that has been
stationary for an hour or two. Remember that the rear
axle assembly must be supported to get a true reading.
How to Check Lubricant
To get an accurate reading, the vehicle should be
on a level surface.
The proper level for the 1500 Series is from
5/8 inch to 1 5/8 inch (15 mm to 40 mm) below
the bottom of the ller plug hole.
The proper level for the 2500 Series is from
0 to 1/2 inch (0 to 13 mm) below the bottom of
the ller plug hole.
Add only enough uid to reach the proper level.
What to Use
To determine what kind of lubricant to use, see
Recommended Fluids and Lubricants on page 6-13.
1500 Series shown, 2500 similar
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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’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 6-13.
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 6-13.
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Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 5-55.
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 5-11
for more information.
2. Remove the two pins on the top of the headlamp
assembly. To remove them, turn the outer pin
outward and pull it straight up. To remove the inner
pin, turn it inward and pull it straight up.
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A. Low-Beam Headlamp
B. High-Beam Headlamp
3. Pull the headlamp assembly out.
4. Unplug the electrical connector.
5. Turn the bulb counterclockwise and remove it from
the headlamp assembly.
6. Put the new bulb into the headlamp assembly and
turn it clockwise until it is tight.
7. Plug in the electrical connector.
8. Put the headlamp assembly back into the vehicle.
9. Install and turn the two pins to secure the headlamp
assembly.
Front Turn Signal, Sidemarker and
Daytime Running Lamps
A. Sidemarker Lamp
B. Retainer ClipC. Front Turn Signal Lamp
D. Daytime Running
Lamp (DRL)
To replace a front turn signal, sidemarker or DRL bulb,
do the following:
1. Open the hood. SeeHood Release on page 5-11
for more information.
2. Remove the headlamp assembly as described
previously. SeeHeadlamps on page 5-50for
more information.
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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.
Side Identication Marker Lamps
To replace a side identication marker bulb,
do the following:
1. Locate the lamp gasket near the rear wheel to
expose the service slot 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
To replace a roof marker lamp bulb, do the following:
1. Remove the
two screws
and lift off
the lens.
2. Install a new
bulb into the
socket and turn
clockwise until
it locks into place.
3. Reinstall the lens and tighten the screws.To replace a center roof marker lamp bulb,
do the following:
1. Remove the six screws from the center roof
marker lamp assembly.
2. Turn the old bulb counterclockwise to remove it
from the socket.
3. Reinstall the lens and tighten the screws.
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Taillamps, Turn Signal, Stoplamps
and Back-up Lamps
A. Turn Signal Lamp
B. Back-up Lamp
C. Stoplamp/TaillampTo replace one of these bulbs, do the following:
1. Remove the
two screws from
the taillamp
assembly.
2. Remove the taillamp assembly.
3. Press the release tab, if equipped, and turn the
socket counterclockwise to remove it from the
taillamp housing.
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4. Pull the old bulb
straight out from
the socket.
5. Press a new bulb into the socket, insert the socket
into the taillamp housing and turn the socket
clockwise into the taillamp housing until it clicks.
6. Reinstall the taillamp assembly.Replacement Bulbs
Exterior Lamp Bulb Number
Back-up Lamp 3157
Daytime Running Lamps (DRL) 4114K
Front Roof Marker Lamp
and Sidemarker194
Front Turn Signal Lamp 3157
Headlamps
High-Beam 9005
Low-Beam 9006
Rear Turn Signal Lamp,
Taillamp and Stoplamp3157
Side Identication Marker Lamp —
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 on page 6-4
for more information.
Replacement blades come in different types and
are removed in different ways. For proper type and
length, seeNormal Maintenance Replacement Parts
on page 6-15.
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.
To replace the rear wiper blade, follow the steps
listed above.
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