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Driving and Operating 237
case will shift to 4m. Turn the knob
to 4
mto display the indicator. With
the vehicle moving less than 5 km/h
(3 mph), and the transmission in
N (Neutral), attempt the shift again.
Shifting Out of 4
n
To shift:
1. The vehicle must be stopped or moving less than 5 km/h
(3 mph) with the transmission
in N (Neutral) and the ignition
on. It is best for the vehicle to
be moving
1.6 to 3.2 km/h (1 to 2 mph).
2. Turn the knob to 4
m, AUTO,
or 2
m. Wait for the 4m, AUTO,
or 2
mindicator light to stop
flashing before shifting the
transmission into gear.
Caution
Shifting the transmission into gear
before the requested mode
indicator light has stopped
flashing could damage the
transfer case.
If the transmission is in gear and/or
moving more than 5 km/h (3 mph),
the 4
m, AUTO, or 2mindicator light
will flash for 30 seconds but will not
complete the shift. With the vehicle
moving less than 5 km/h (3 mph),
and the transmission in N (Neutral),
attempt the shift again.
Shifting Into N (Neutral)
To shift into N (Neutral):
1. Park the vehicle on a level surface.
2. Set the parking brake and press and hold the brake
pedal. See Parking Brake
0 240.
3. Start the vehicle or turn the ignition on. 4. Shift the transmission to
N (Neutral).
5. Shift the transfer case to 2
m.
6. Turn the transfer case knob clockwise to N (Neutral) until it
stops and hold it there until the
N (Neutral) light starts blinking.
This will take at least
10 seconds. Then slowly
release the knob to the 4
n
position. The N (Neutral) light
will come on when the transfer
case shift to N (Neutral) is
complete.
7. With the engine running, verify that the transfer case is in
N (Neutral) by shifting the
transmission to R (Reverse),
then shift the transmission to
D (Drive). There should be no
movement of the vehicle while
shifting the transmission.
8. Turn the engine off, and the ignition to ACC/ACCESSORY.
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Vehicle Care 313
Turn the pressure cap slowly
counterclockwise about one full
turn. If a hiss is heard, wait for
that to stop. A hiss means
there is still some pressure left.
2. Keep turning the pressure cap slowly, and remove it.
3. Fill the coolant surge tank with the proper mixture to the full
cold mark.
4. With the coolant surge tank pressure cap off, start the
engine and let it run until the
engine coolant temperature
gauge indicates approximately
90 °C (195 °F).
By this time, the coolant level
inside the coolant surge tank
may be lower. If the level is
lower, add more of the proper
mixture to the coolant surge
tank until the level reaches the
full cold mark.
5. Replace the pressure cap tightly. 6. Verify coolant level after the
engine is shut off and the
coolant is cold. If necessary,
repeat coolant fill procedure
Steps 1–6.
Caution
If the pressure cap is not tightly
installed, coolant loss and engine
damage may occur. Be sure the
cap is properly and tightly
secured.
Engine Overheating
Caution
Do not run the engine if there is a
leak in the engine cooling system.
This can cause a loss of all
coolant and can damage the
system and vehicle. Have any
leaks fixed right away.
The vehicle has several indicators
to warn of engine overheating. There is a coolant temperature
gauge in the vehicle's instrument
cluster. See
Engine Coolant
Temperature Gauge 0148.
In addition, there are ENGINE
OVERHEATED STOP ENGINE,
ENGINE OVERHEATED IDLE
ENGINE, and ENGINE POWER IS
REDUCED messages in the Driver
Information Center (DIC).
If the decision is made not to lift the
hood when this warning appears,
get service help right away. See
Roadside Assistance Program
0 415.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
Check to see if the engine cooling
fan(s) are running. If the engine is
overheating, the fans should be
running. If they are not, do not
continue to run the engine. Have the
vehicle serviced.
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GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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326 Vehicle Care
Bulb Replacement
For the proper type of replacement
bulbs, or any bulb changing
procedure not listed in this section,
contact your dealer.
Caution
Do not replace incandescent
bulbs with aftermarket LED
replacement bulbs. This can
cause damage to the vehicle
electrical system.
High Intensity Discharge
(HID) Lighting
{Warning
The High Intensity Discharge
(HID) lighting system operates at
a very high voltage. If you try to
service any of the system
components, you could be
seriously injured. Have your
dealer or a qualified technician
service them.
After an HID headlamp bulb has
been replaced, the beam might be a
slightly different shade than it was
originally. This is normal.
LED Lighting
This vehicle has several LED lamps.
For replacement of any LED lighting
assembly, contact your dealer.
Fog Lamps
To replace the front fog lamp bulb: 1. Locate the fog lamp under the front bumper.
2. Disconnect the electrical connector from the fog lamp
bulb assembly by pressing the
connector release.
3. Turn the bulb counterclockwise to remove it from the housing.
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Vehicle Care 327
Back-Up Lamps
To replace a back-up bulb:1. Open the liftgate. See Liftgate
0 47.
2. Remove the taillamp closeout
cover from the lamp assembly
by pulling rearward from the
top and bottom at the same
time to unfasten the snap tabs.
3. Remove the two screws from
the taillamp assembly.
4. Pull the taillamp assembly straight back to remove.5. Turn the bulb socketcounterclockwise to remove it
from the taillamp assembly.
6. Pull the bulb straight out from the socket.
7. Put a new bulb into the socket, insert it into the taillamp
assembly, and turn the bulb
socket clockwise until it clicks.
8. Reinstall the taillamp assembly and tighten the screws.
9. Reinstall the taillamp cover by snapping it into place.
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328 Vehicle Care
License Plate Lamp
Passenger Side Shown, DriverSide Similar
1. Bulb Socket
2. Bulb
3. Lamp Assembly
To replace one of these bulbs:
1. Push the lamp assembly (3) toward the center of the
vehicle.
2. Pull the lamp assembly down to remove. 3. Turn the bulb socket (1)
counterclockwise to remove it
from the lamp assembly (3).
4. Pull the bulb (2) straight out of the bulb socket (1).
5. Push the replacement bulb straight into the bulb socket
and turn the bulb socket
clockwise to install it into the
lamp assembly.
6. Push the lamp assembly back into position until the release
tab locks into place.
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GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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364 Vehicle Care
1. Jack Knob
2. Wing Nut Retaining theWheel Blocks
3. Wing Nut Retaining the Tool Bag1. Pull to open the trim panel door.
The third row driver side seat
may need to be folded to
access the trim panel door.
2. Lift the acoustic pad to access the jack and tools.
3. Turn the wing nut retaining the tool bag (3) counterclockwise to
remove it.
Pull the tool bag toward the
front of the vehicle and lift the
rear portion of the bag upward
to remove it. 4. Turn the jack knob (1)
counterclockwise to release the
jack and wheel blocks from the
bracket.
5. Turn the wing nut retaining the wheel blocks (2)
counterclockwise to remove the
wheel blocks and the wheel
block retainer.
Use the following tools:
1. Jack
2. Wheel Blocks
3. Jack Handle
4. Jack Handle Extensions
5. Wheel Wrench
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Vehicle Care 365
To access the spare tire, refer to the
following graphics and instructions:
1. Hoist Assembly
2. Hoist Shaft
3. Hoist Shaft AccessCover/Hole
4. Jack Handle Extensions
5. Wheel Wrench
6. Spare Tire Lock
7. Hoist End of Extension Tool
8. Hoist Shaft Access Hole
9. Spare Tire (Valve Stem Pointed Down)
10. Tire/Wheel Retainer
11. Hoist Cable
1. Open the hoist shaft access door (3) on the bumper to
access the spare tire lock (6).
If equipped with a hitch cover,
turn the hitch cover retainers
counterclockwise and pull the
cover downward to remove it
before removing the hoist shaft
access door.
2. To remove the spare tire lock (6), insert the ignition key, turn
it clockwise and then pull it
straight out.3. Assemble the two jack handleextensions (4) and wheel
wrench (5), as shown.
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GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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366 Vehicle Care
4. Insert the open end of theextension (7) through the hole
in the rear bumper (8) (hoist
shaft access hole).
Be sure the hoist end of the
extension (7) connects to the
hoist shaft. The ribbed square
end of the extension is used to
lower the spare tire.
5. Turn the wheel wrench counterclockwise to lower the
spare tire to the ground.
Continue to turn the wheel
wrench until the spare tire can
be pulled out from under the
vehicle.
6. Pull the spare tire out from under the vehicle.7. Tilt the tire toward the vehiclewith some slack in the cable to
access the tire/wheel retainer.
Tilt the retainer and pull it and
the cable and spring through
the center of the wheel.
8. Put the spare tire near the flat tire.
Removing the Flat Tire and
Installing the Spare Tire
1. Do a safety check beforeproceeding. See If a Tire Goes
Flat 0362 for more information.
2. If the vehicle has a center cap
that covers the wheel
fasteners, place the chisel end
of the wheel wrench in the slot
on the wheel and gently pry the
cap out.
If the wheel has a bolt-on hub
cap, loosen the plastic nut caps
by turning the wheel wrench
counterclockwise. The plastic
nut caps will be retained in the
hub cap after it is removed
from the wheel.