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Black plate (26,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
10-26 Vehicle Care
The proper level is 1.0 mm to
19.0 mm (0.04 in to 0.7 in) below
the bottom of the fill hole, located on
the rear axle. Add only enough fluid
to reach the proper level.
What to Use
Refer toRecommended Fluids and
Lubricants on page 11-12 to
determine what kind of lubricant
to use.
Noise Control System
The following information relates to
compliance with federal noise
emission standards for vehicles with
a Gross Vehicle Weight Rating
(GVWR) of more than 4 536 kg
(10,000 lb). The noise control
system warranty is given in your
warranty manual.
These standards apply only to
vehicles sold in the United States. Federal law prohibits the following
acts or the causing thereof:
1. The removal or rendering
inoperative by any person, other
than for purposes of
maintenance, repair or
replacement, of any device or
element of design incorporated
into any new vehicle for the
purpose of noise control, prior to
its sale or delivery to the ultimate
purchaser or while it is in use; or
2. The use of the vehicle after such device or element of design has
been removed or rendered
inoperative by any person.
Among those acts presumed to
constitute tampering are the acts
listed below.
Insulation:
Removal of the noise shields or any
underhood insulation. Engine:
Removal or rendering engine speed
governor, if the vehicle has one,
inoperative so as to allow engine
speed to exceed manufacturer
specifications.
Fan and Drive:
.Removal of fan clutch, if the
vehicle has one, or rendering
clutch inoperative.
.Removal of the fan shroud, if the
vehicle has one.
Air Intake:
.Removal of the air cleaner
silencer.
.Modification of the air cleaner.
Exhaust:
.Removal of the muffler and/or
resonator.
.Removal of the exhaust pipes
and exhaust pipe clamps.
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Black plate (27,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
Vehicle Care 10-27
Starter Switch Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle.
2. Apply both the parking brake and the regular brake.
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.
Automatic Transmission
Shift Lock Control
Function Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface.
2. Apply the parking brake. Be ready to apply the regular brake
immediately if the vehicle begins
to move.
3. With the engine off, turn the ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Ignition Transmission
Lock Check
If equipped with a key type ignition,
while parked and with the parking
brake set, try to turn the ignition to
LOCK/OFF in each shift lever
position.
.The ignition should turn to
LOCK/OFF only when the shift
lever is in P (Park).
.The ignition key should come
out only in LOCK/OFF.
Contact your dealer if service is
required.
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Black plate (28,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
10-28 Vehicle Care
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake.
.To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.
.To check the P (Park)
mechanism's holding ability:
With the engine running, shift to
P (Park). Then release the
parking brake followed by the
regular brake.
Contact your dealer if service is
required.
Wiper Blade Replacement
Windshield wiper blades should be
inspected for wear or cracking.
For the proper type and size, see
Maintenance Replacement Parts on
page 11-13.
Front Wiper Blade
Replacement
To replace the wiper blade
assembly:
1. Pull the windshield wiper assembly away from the
windshield.
2. Lift up on the latch in the middleof the wiper blade where the
wiper arm attaches.
3. With the latch open, pull the wiper blade down toward the
windshield far enough to release
it from the J-hooked end of the
wiper arm.
4. Remove the wiper blade. Allowing the wiper blade arm to
touch the windshield when no
wiper blade is installed could
damage the windshield. Any
damage that occurs would not
be covered by the vehicle
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Black plate (29,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
Vehicle Care 10-29
warranty. Do not allow the wiper
blade arm to touch the
windshield.
5. Reverse Steps 1–3 for wiper blade replacement.
Rear Wiper Blade Replacement
To replace the rear wiper blade:
1. Pull the wiper blade assemblyaway from the backglass.
The rear wiper blade will not lock
in a vertical position so care
should be used when pulling it
away from the vehicle.
2. Push the release lever (2) todisengage the hook and push
the wiper arm (1) out of the
blade assembly (3).
3. Push the new blade assembly securely in the wiper arm hook
until the release lever clicks into
place.
4. Return the wiper arm and blade assembly to the rest position on
the glass.
Glass Replacement
If the windshield or front side glass
must be replaced, see your dealer
to determine the correct
replacement glass.
Windshield Replacement
The windshield is part of the HUD
system. If the vehicle has to have
the windshield replaced, get one
that is designed for HUD or the
HUD image may look out of focus.
Headlamp Aiming
Headlamp aim has been preset and
should need no further adjustment.
If the vehicle is damaged in a crash,
the headlamp aim may be affected.
If adjustment to the headlamps is
necessary, see your dealer.
Page 333 of 459

Black plate (30,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
10-30 Vehicle Care
Bulb Replacement
For the proper type of replacement
bulbs, seeReplacement Bulbs on
page 10-33.
For any bulb‐changing procedure
not listed in this section, contact
your dealer.
High Intensity Discharge
(HID) Lighting
{Warning
The high intensity discharge
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.
Headlamps
Driver Side
1. Low-Beam Headlamp
2. High-Beam Headlamp
See your dealer for passenger side
replacement.
Headlamp
1. Open the hood. See Hood on
page 10-4
2. Remove the headlamp bulb assembly cover by turning it
counterclockwise.
3. Turn the bulb socket counterclockwise to remove it
from the headlamp assembly
and pull it straight out.
4. Unplug the electrical connector from the old bulb by releasing
the clip on the bulb socket.
Front Turn Signal Lamps
1. Open the hood. See Hood on
page 10-4
2. Reach in and access the bulb socket from inside the engine
compartment.
3. Turn the bulb socket counterclockwise to remove it
from the headlamp assembly
and pull it straight out.
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Black plate (31,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
Vehicle Care 10-31
4. Remove the bulb by pulling itstraight out of the socket bulb
socket.
5. Replace it with a new bulb.
6. Reinstall the new bulb socket into the headlamp assembly and
turn it clockwise to secure.
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps
1. Back-up Lamp
2. Stoplamp/Turn Signal Lamp
The taillamp on this vehicle is an
LED. For replacement, contact your
dealer.
To replace one of these bulbs:
1. Open the liftgate. See Liftgate
on page 2-19.
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 socket counterclockwise to remove it
from the taillamp assembly.
6. Pull the bulb straight out from the socket.
7. Press a new bulb into the socket, insert it into the taillamp
assembly, and turn the bulb
socket clockwise until it clicks.
Page 335 of 459
Black plate (32,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
10-32 Vehicle Care
8. Reinstall the taillamp assemblyand tighten the screws.
9. Reinstall the taillamp cover by snapping it into place.License Plate Lamp
Passenger Side Shown, Driver
Side 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).
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Black plate (33,1)GMC 2015i Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431503) - 2015 - crc - 8/11/14
Vehicle Care 10-33
5. Push the replacement bulbstraight 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.
Replacement Bulbs
Exterior Lamp Bulb
Number
Back-up Lamp 921
High-Beam
Headlamp 9005 LL
Low-Beam
Headlamp H11 LL
License
Plate Lamp W5W
For replacement bulbs not listed
here, contact your dealer.
Electrical System
Electrical System
Overload
The vehicle has fuses to protect
against an electrical system
overload. Fuses also protect power
devices in the vehicle.
Replace a bad fuse with a new one
of the identical size and rating.
If there is a problem on the road and
a fuse needs to be replaced, there
are some spare fuses and a fuse
puller in the Instrument Panel Fuse
Block. The same amperage fuse
can also be borrowed. Choose
some feature of the vehicle that is
not needed to use and replace it as
soon as possible.
Headlamp Wiring
An electrical overload may cause
the lamps to go on and off, or in
some cases to remain off. Have the headlamp wiring checked right away
if the lamps go on and off or
remain off.
Windshield Wipers
If the wiper motor overheats due to
heavy snow or ice, the windshield
wipers will stop until the motor cools
and will then restart.
Although the circuit is protected
from electrical overload, overload
due to heavy snow or ice may
cause wiper linkage damage.
Always clear ice and heavy snow
from the windshield before using the
windshield wipers.
If the overload is caused by an
electrical problem and not snow or
ice, be sure to get it fixed.
Fuses
The wiring circuits in the vehicle are
protected from short circuits by
fuses. This greatly reduces the
chance of fires caused by electrical
problems.