
GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 287Caution (Continued)automatic transmission fluid listed
in Recommended Fluids and
Lubricants 0 379 .
Change the fluid and filter at the
scheduled maintenance intervals
listed in Maintenance Schedule
0 370 . Be sure to use the
transmission fluid listed in
Recommended Fluids and
Lubricants 0 379 .
How to Check Automatic
Transmission Fluid
Caution
Too much or too little fluid can
damage the transmission. Too
much can mean that some of the
fluid could come out and fall on
hot engine parts or exhaust
system parts, starting a fire. Too
little fluid could cause the
(Continued) Caution (Continued) transmission to overheat. Be sure
to get an accurate reading if
checking the transmission fluid.
Before checking the fluid level,
prepare the vehicle:
1. Start the engine and park the
vehicle on a level surface.
Keep the engine running.
2. Apply the parking brake and
place the shift lever in P (Park).
3. With your foot on the brake
pedal, move the shift lever
through each gear range,
pausing for about
three seconds in each range.
Then, move the shift lever back
to P (Park).
4. Allow the engine to idle (500 –
800 rpm) for at least
one minute. Slowly release the
brake pedal.
5. Keep the engine running and
check the transmission fluid
temperature on the Driver Information Center (DIC). See
Driver Information Center (DIC)
0 151 .
6. Using the transmission fluid
temperature reading, determine
and perform the appropriate
check procedure. If the
transmission fluid temperature
reading is not within the
required temperature ranges,
allow the vehicle to cool,
or operate the vehicle until the
appropriate transmission fluid
temperature is reached.
Cold Check Procedure
Use this procedure only as a
reference to determine if the
transmission has enough fluid to be
operated safely until a hot check
procedure can be made. The hot
check procedure is the most
accurate method to check the fluid
level. Perform the hot check
procedure at the first opportunity.
Use this cold check procedure to
check fluid level when the
transmission temperature is
between 27 °C and 32 °C (80 °F and
90 °F).

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
290 Vehicle Care Change the fluid and filter at the
scheduled maintenance intervals
listed in Maintenance Schedule
0 370 . Be sure to use the
transmission fluid listed in
Recommended Fluids and
Lubricants 0 379 .
Engine Air Cleaner/Filter See Engine Compartment Overview
0 280 for the location of the engine
air cleaner/filter.
When to Inspect the Engine Air
Cleaner/Filter For intervals on changing and
inspecting the engine air cleaner/
filter, see Maintenance Schedule
0 370 .
How to Inspect the Engine Air
Cleaner/Filter
Do not start the engine or have the
engine running with the engine air
cleaner/filter housing open. Before
removing the engine air cleaner/
filter, make sure that the engine air
cleaner/filter housing and nearby
components are free of dirt and
debris. Remove the engine air cleaner/filter. Lightly tap and shake
the engine air cleaner/filter (away
from the vehicle), to release loose
dust and dirt. Inspect the engine air
cleaner/filter for damage, and
replace if damaged. Do not clean
the engine air cleaner/filter or
components with water or
compressed air.
To inspect or replace the engine air
cleaner/filter:
1. Screws (4)
2. Electrical Connector
3. Air Duct Clamp 1. Locate the air cleaner/filter
assembly. See Engine
Compartment Overview 0 280 .
2. Disconnect the outlet duct by
loosening the air duct
clamp (3).
3. Disconnect the electrical
connector (2) and the
connector harness from the
cover.
4. Remove the four screws (1) on
top of the cover of the housing
and lift up the cover.
5. Remove the engine air cleaner/
filter from the housing. Take
care to dislodge as little dirt as
possible.
6. Clean the engine air cleaner/
filter sealing surfaces and the
housing.
7. Inspect or replace the engine
air cleaner/filter.
8. Reverse Steps 2-4 to reinstall
the filter cover housing.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
298 Vehicle Care Checking Brake Fluid
With the vehicle in P (Park) on a
level surface, the brake fluid level
should be between the minimum
and maximum marks on the brake
fluid reservoir.
There are only two reasons why the
brake fluid level in the reservoir may
go down:
.
Normal brake lining wear. When
new linings are installed, the
fluid level goes back up.
.
A fluid leak in the brake
hydraulic system. Have the
brake hydraulic system fixed.
With a leak, the brakes will not
work well.
Always clean the brake fluid
reservoir cap and the area around
the cap before removing it.
Do not top off the brake fluid.
Adding fluid does not correct a leak.
If fluid is added when the linings are
worn, there will be too much fluid
when new brake linings are
installed. Add or remove fluid, as
necessary, only when work is done
on the brake hydraulic system. { WarningIf too much brake fluid is added, it
can spill on the engine and burn,
if the engine is hot enough. You
or others could be burned, and
the vehicle could be damaged.
Add brake fluid only when work is
done on the brake hydraulic
system.
When the brake fluid falls to a low
level, the brake warning light comes
on. See Brake System Warning
Light 0 145 .
Brake fluid absorbs water over time
which degrades the effectiveness of
the brake fluid. Replace brake fluid
at the specified intervals to prevent
increased stopping distance. See
Maintenance Schedule 0 370 .
What to Add
Use only GM approved DOT 3
brake fluid from a clean, sealed
container. See Recommended
Fluids and Lubricants 0 379 .{ WarningThe wrong or contaminated brake
fluid could result in damage to the
brake system. This could result in
the loss of braking leading to a
possible injury. Always use the
proper GM approved brake fluid.
CautionIf brake fluid is spilled on the
vehicle's painted surfaces, the
paint finish can be damaged.
Immediately wash off any painted
surface.
Battery - North America The original equipment battery is
maintenance free. Do not remove
the cap and do not add fluid.
Refer to the replacement number
shown on the original battery label
when a new battery is needed. See
Engine Compartment Overview
0 280 for battery location.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 299
{ WarningWARNING: Battery posts,
terminals, and related
accessories contain lead and lead
compounds, chemicals known to
the State of California to cause
cancer and birth defects or other
reproductive harm. Batteries also
contain other chemicals known to
the State of California to cause
cancer. WASH HANDS AFTER
HANDLING. For more information
go to www.P65Warnings.ca.gov/
passenger-vehicle.
See California Proposition
65 Warning 0 277 and the back
cover.
Vehicle Storage
{ Warning
Batteries have acid that can burn
you and gas that can explode.
You can be badly hurt if you are
(Continued) Warning (Continued) not careful. See Jump Starting -
North America 0 351 for tips on
working around a battery without
getting hurt.
Infrequent Usage: Remove the
black, negative ( − ) cable from the
battery to keep the battery from
running down.
Extended Storage: Remove the
black, negative ( − ) cable from the
battery or use a battery trickle
charger.
Four-Wheel Drive Transfer Case
When to Check Lubricant
Refer to Maintenance Schedule
0 370 to determine when to check
the lubricant. How to Check Lubricant
Automatic Transfer Case
1. Fill Plug
2. Drain Plug
To get an accurate reading, the
vehicle should be on a level
surface.
If the level is below the bottom of
the fill plug (1) hole, located on the
transfer case, some lubricant will
need to be added. Add enough
lubricant to raise the level to the
bottom of the fill plug (1) hole. Use
care not to overtighten the plug.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
300 Vehicle Care When to Change Lubricant
Refer to Maintenance Schedule
0 370 to determine how often to
change the lubricant.
What to Use
Refer to Recommended Fluids and
Lubricants 0 379 to determine what
kind of lubricant to use.
Front Axle When to Check and Change
Lubricant
It is not necessary to regularly
check front axle fluid unless a leak
is suspected, or an unusual noise is
heard. A fluid 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. 1. Fill Plug
2. Drain Plug
.
When the differential is cold, add
enough lubricant to raise the
level from 0 mm (0 in) to 3.2 mm
(1/8 in) below the fill
plug (1) hole.
.
When the differential is at
operating temperature (warm),
add enough lubricant to raise the
level to the bottom of the fill
plug (1) hole.
What to Use
Refer to Recommended Fluids and
Lubricants 0 379 to determine what
kind of lubricant to use. Rear Axle When to Check Lubricant It is not necessary to regularly
check rear axle fluid unless a leak is
suspected or an unusual noise is
heard. A fluid loss could indicate a
problem. Have it inspected and
repaired.
All axle assemblies are filled by
volume of fluid during production.
They are not filled to reach a certain
level. When checking the fluid level
on any axle, variations in the
readings can be caused by factory
fill differences between the minimum
and the maximum fluid volume.
Also, if a vehicle has just been
driven before checking the fluid
level, it may appear lower than
normal because fluid has traveled
out along the axle tubes and has
not drained back to the sump area.
Therefore, a reading taken
five minutes after the vehicle has
been driven will appear to have a
lower fluid level than a vehicle that
has been stationary for an hour or

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 301two. The rear axle assembly must
be supported on a flat, level surface
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 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 to Recommended Fluids and
Lubricants 0 379 to determine what
kind of lubricant to use.
Noise Control System Noise Emission Warranty
General Motors warrants to the first
person who purchases this vehicle
for purposes other than resale and
to each subsequent purchaser that
this vehicle as manufactured by
General Motors was designed, built
and equipped to conform at the time
it left General Motors control with all
applicable U.S. EPA Noise Control
Regulations. This warranty covers
this vehicle as designed, built and
equipped by General Motors and is
not limited to any particular part,
component or system of the vehicle
manufactured by General Motors.
Defects in design, assembly or any
part, component or system of the
vehicle manufactured by General
Motors, which at the time it left
General Motors control caused noise emissions to exceed Federal
standards, are covered by the
warranty for the life of the vehicle.
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 lbs). The Maintenance
Schedule provides information on
maintaining the noise control system
to minimize degradation of the noise
emission control system during the
life of the vehicle. The noise control
system warranty is given in the
vehicle warranty booklet.
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

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 305Driver Assistance Systems When a windshield replacement is
needed and the vehicle is equipped
with a front-looking camera sensor
for the Driver Assistance Systems,
the windshield must be installed
according to GM specifications for
these systems to work properly. If it
is not, there may be unexpected
behavior and/or messages from
these systems.
Gas Strut(s) This vehicle is equipped with gas
strut(s) to provide assistance in
lifting and holding open the hood/
trunk/liftgate system in full open
position.
{ Warning
If the gas struts that hold open
the hood, trunk, and/or liftgate fail,
you or others could be seriously
injured. Take the vehicle to your
dealer for service immediately.
Visually inspect the gas struts for
(Continued) Warning (Continued) signs of wear, cracks, or other
damage periodically. Check to
make sure the hood/trunk/liftgate
is held open with enough force.
If struts are failing to hold the
hood/trunk/liftgate, do not
operate. Have the vehicle
serviced.
CautionDo not apply tape or hang any
objects from gas struts. Also do
not push down or pull on gas
struts. This may cause damage to
the vehicle.
See Maintenance Schedule 0 370 . Hood
Trunk

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
334 Vehicle Care .
The tread or sidewall is
cracked, cut, or snagged
deep enough to show cord or
fabric..
The tire has a bump, bulge,
or split..
The tire has a puncture, cut,
or other damage that cannot
be repaired well because of
the size or location of the
damage.
Tire Rotation Tires should be rotated every
12 000 km (7,500 mi). See
Maintenance Schedule 0 370 .
Tires are rotated to achieve a
uniform wear for all tires. The
first rotation is the most
important.
Anytime unusual wear is
noticed, rotate the tires as soon
as possible, check for proper tire
inflation pressure, and check for
damaged tires or wheels. If the
unusual wear continues after the rotation, check the wheel
alignment.
See When It Is Time for New
Tires 0 335 and Wheel
Replacement 0 339 .
Use this rotation pattern when
rotating the tires.
Do not include the spare tire in
the tire rotation.
Adjust the front and rear tires to
the recommended inflation
pressure on the Tire and
Loading Information label after the tires have been rotated.
See Tire Pressure 0 327 and
Vehicle Load Limits 0 200 .
Reset the Tire Pressure Monitor
System. See Tire Pressure
Monitor Operation 0 330 .
Check that all wheel nuts are
properly tightened. See “ Wheel
Nut Torque ” under Capacities
and Specifications 0 384 .
{ WarningRust or dirt on a wheel, or on the
parts to which it is fastened, can
make wheel nuts become loose
after time. The wheel could come
off and cause an accident. When
changing a wheel, remove any
rust or dirt from places where the
wheel attaches to the vehicle. In
an emergency, a cloth or a paper
towel can be used; however, use
a scraper or wire brush later to
remove all rust or dirt.