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GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
280 Driving and Operating
Always know the maximum speed
rating for the trailer tires before
driving. This may be significantly
lower than the vehicle tire speed
rating. The speed rating may be on
the trailer tire sidewall. If the speed
rating is not shown, the default
trailer tire speed rating is 105 km/h
(65 mph).Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC) is
used for vehicle service and
Emission Inspection/Maintenance
testing. SeeMalfunction Indicator
Lamp (Check Engine Light) 0136
. A device connected to the DLC
— such as an aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle
systems. This could affect vehicle
operation and cause a crash.
Such devices may also access
information stored in the vehicle’s
systems.
Caution
Some electrical equipment can
damage the vehicle or cause
components to not work and
would not be covered by the
vehicle warranty. Always check
with your dealer before adding
electrical equipment.
Add-on equipment can drain the
vehicle's 12-volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicle 084 and
Adding Equipment to the
Airbag-Equipped Vehicle 084.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Vehicle Care 281
Vehicle Care
General Information
General Information . . . . . . . . . . 282
California Proposition65 Warning . . . . . . . . . . . . . . . . . 282
California Perchlorate Materials Requirements . . . . . 283
Accessories and Modifications . . . . . . . . . . . . . . . . 283
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 283
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 284
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 286
Engine Oil . . . . . . . . . . . . . . . . . . . . 289
Engine Oil Life System . . . . . . . 291
Automatic Transmission Fluid (6-Speed Transmission) . . . . . 292
Automatic Transmission Fluid (10-Speed Transmission) . . . 295
Engine Air Cleaner/Filter . . . . . . 296
Cooling System . . . . . . . . . . . . . . 297
Engine Overheating . . . . . . . . . . 300
Engine Fan . . . . . . . . . . . . . . . . . . . 302
Washer Fluid . . . . . . . . . . . . . . . . . 302
Brakes . . . . . . . . . . . . . . . . . . . . . . . 303 Brake Fluid . . . . . . . . . . . . . . . . . . . 304
Battery - North America . . . . . . 305
Four-Wheel Drive . . . . . . . . . . . . . 305
Front Axle . . . . . . . . . . . . . . . . . . . . 306
Rear Axle . . . . . . . . . . . . . . . . . . . . 306
Noise Control System . . . . . . . . 306
Starter Switch Check . . . . . . . . . 308
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 308
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 308
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 309
Wiper Blade Replacement . . . . 309
Glass Replacement . . . . . . . . . . 310
Windshield Replacement . . . . . 310
Gas Strut(s) . . . . . . . . . . . . . . . . . . 310
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 312
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 312
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 312
LED Lighting . . . . . . . . . . . . . . . . . 312
Fog Lamps . . . . . . . . . . . . . . . . . . . 312
Back-Up Lamps . . . . . . . . . . . . . . 313
License Plate Lamp . . . . . . . . . . 314
Electrical System
Electrical System Overload . . . 314
Fuses and Circuit Breakers . . . 315
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 315
Instrument Panel Fuse Block
(Right) . . . . . . . . . . . . . . . . . . . . . . 320
Instrument Panel Fuse Block (Left) . . . . . . . . . . . . . . . . . 323
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 325
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 326
All-Season Tires . . . . . . . . . . . . . . 327
Winter Tires . . . . . . . . . . . . . . . . . . 328
Low-Profile Tires . . . . . . . . . . . . . 328
All-Terrain Tires . . . . . . . . . . . . . . . 328
Tire Sidewall Labeling . . . . . . . . 329
Tire Designations . . . . . . . . . . . . . 330
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 331
Tire Pressure . . . . . . . . . . . . . . . . . 333
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 334
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 335
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 336
Tire Inspection . . . . . . . . . . . . . . . . 340

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Vehicle Care 283
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag
initiators, seat belt pretensioners,
and lithium batteries contained in
electronic keys, may contain
perchlorate materials. Perchlorate
Material–special handling may
apply. See www.dtsc.ca.gov/
hazardouswaste/perchlorate.
Accessories and
Modifications
Adding non-dealer accessories or
making modifications to the vehicle
can affect vehicle performance and
safety, including such things as
airbags, braking, stability, ride and
handling, emissions systems,
aerodynamics, durability, and
electronic systems like antilock
brakes, traction control, and stability
control. These accessories or
modifications could even cause
malfunction or damage not covered
by the vehicle warranty. Damage to suspension components
caused by modifying vehicle height
outside of factory settings will not be
covered by the vehicle warranty.
Damage to vehicle components
resulting from modifications or the
installation or use of non-GM
certified parts, including control
module or software modifications, is
not covered under the terms of the
vehicle warranty and may affect
remaining warranty coverage for
affected parts.
GM Accessories are designed to
complement and function with other
systems on the vehicle. See your
dealer to accessorize the vehicle
using genuine GM Accessories
installed by a dealer technician.
Also, see
Adding Equipment to the
Airbag-Equipped Vehicle 084.
Vehicle Checks
Doing Your Own
Service Work
{Warning
It can be dangerous to work on
your vehicle if you do not have
the proper knowledge, service
manual, tools, or parts. Always
follow owner ’s manual procedures
and consult the service manual
for your vehicle before doing any
service work.
If doing some of your own service
work, use the proper service
manual. It tells you much more
about how to service the vehicle
than this manual can. To order the
proper service manual, see
Publication Ordering Information
0 405.
This vehicle has an airbag system.
Before attempting to do your own
service work, see Servicing the
Airbag-Equipped Vehicle 084.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Vehicle Care 287
1. Positive (+) Terminal. SeeJump Starting - North America
0360.
2. Battery - North America 0305.
3. Coolant Surge Tank and Pressure Cap. See Cooling
System 0297.
4. Engine Air Cleaner/Filter 0296.
5. Automatic Transmission Dipstick. See “How to Check
Automatic Transmission Fluid”
under Automatic Transmission
Fluid (6-Speed Transmission)
0 292 or
Automatic Transmission Fluid
(10-Speed Transmission)
0 295.
6. Remote Negative (–) Location (Out of View). See Jump
Starting - North America 0360.
7. Engine Cooling Fans (Out of View). See Cooling System
0 297.
8. Engine Oil Fill Cap. See “When
to Add Engine Oil” under
Engine Oil 0289. 9. Engine Oil Dipstick. See
“Checking Engine Oil” under
Engine Oil 0289.
10. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid
0 302.
11. Brake Fluid Reservoir. See Brake Fluid 0304.
12. Engine Compartment Fuse
Block 0315.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Vehicle Care 289
1. Positive (+) Terminal. SeeJump Starting - North America
0360.
2. Battery - North America 0305.
3. Coolant Surge Tank and Pressure Cap. See Cooling
System 0297.
4. Engine Air Cleaner/Filter 0296.
5. Remote Negative (–) Location (Out of View). See Jump
Starting - North America 0360.
6. Engine Cooling Fans (Out of View). See Cooling System
0 297.
7. Engine Oil Fill Cap. See “When
to Add Engine Oil” under
Engine Oil 0289.
8. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil 0289.
9. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid
0 302.
10. Brake Fluid Reservoir. See Brake Fluid 0304. 11.
Engine Compartment Fuse
Block 0315.
Engine Oil
To ensure proper engine
performance and long life, careful
attention must be paid to engine oil.
Following these simple, but
important steps will help protect
your investment:
.
Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“Selecting the Right Engine Oil”
in this section.
. Check the engine oil level
regularly and maintain the
proper oil level. See “Checking
Engine Oil” and“When to Add
Engine Oil” in this section.
. Change the engine oil at the
appropriate time. See Engine Oil
Life System 0291.
. Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.
Checking Engine Oil
If equipped, the ENGINE OIL LOW
ADD OIL message displays when
the engine oil level may be too low.
Check the oil level before filling to
the recommended level. If the oil is
not low and this message remains
on, see your dealer.
Check the engine oil level regularly,
every 650 km (400 mi), especially
prior to a long trip. The engine oil
dipstick handle is a loop. See
Engine Compartment Overview
0286 for the location.
{Warning
The engine oil dipstick handle
may be hot; it could burn you.
Use a towel or glove to touch the
dipstick handle.
Follow these guidelines:
. To get an accurate reading, park
the vehicle on level ground.
Check the engine oil level after
the engine has been off for at
least two hours. Checking the

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
292 Vehicle Care
best conditions, the oil life system
may indicate that an oil change is
not necessary for up to a year. The
engine oil and filter must be
changed at least once a year and,
at this time, the system must be
reset. Your dealer has trained
service people who will perform this
work and reset the system. It is also
important to check the oil regularly
over the course of an oil drain
interval and keep it at the proper
level.
If the system is ever reset
accidentally, the oil must be
changed at 5 000 km (3,000 mi)
since the last oil change.
Remember to reset the oil life
system whenever the oil is changed.
How to Reset the Engine Oil
Life System
Reset the system whenever the
engine oil is changed so that the
system can calculate the next
engine oil change. Always reset the
engine oil life to 100% after every oil
change. It will not reset itself. To
reset the engine oil life system:1. Display the REMAINING OIL
LIFE on the DIC. See Driver
Information Center (DIC) 0144.
2. Press and hold
V. The oil life
will change to 100%.
The oil life system can also be reset
as follows: 1. Display the REMAINING OIL LIFE on the DIC. See Driver
Information Center (DIC) 0144.
2. Fully press the accelerator pedal slowly three times within
five seconds.
3. Display the REMAINING OIL LIFE on the DIC. If the display
shows 100%, the system is
reset.
If the CHANGE ENGINE OIL SOON
message comes back on when the
vehicle is started and/or the
REMAINING OIL LIFE is near 0%,
the engine oil life system has not
been reset. Repeat the procedure.
Automatic Transmission
Fluid (6-Speed
Transmission)
When to Check and Change
Automatic Transmission Fluid
It is usually not necessary to check
the transmission fluid level. The only
reason for fluid loss is a
transmission leak or overheated
transmission. If a small leak is
suspected, then use the following
checking procedures to check the
fluid level. However, if there is a
large leak, then it may be necessary
to have the vehicle towed to a
dealer service department and have
it repaired before driving the vehicle
further.
Caution
Use of the incorrect automatic
transmission fluid may damage
the vehicle, and the damage may
not be covered by the vehicle
warranty. Always use the correct (Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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296 Vehicle Care
transmission fluid listed in
Recommended Fluids and
Lubricants0388.
Engine Air Cleaner/Filter
See Engine Compartment Overview
0 286 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
0 379.
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 0286. 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./
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Vehicle Care 297
{Warning
Operating the engine with the air
cleaner/filter off can cause you or
others to be burned. Use caution
when working on the engine. Do
not start the engine or drive the
vehicle with the air cleaner/filter
off, as flames may be present if
the engine backfires.
Caution
If the air cleaner/filter is off, dirt
can easily get into the engine,
which could damage it. Always
have the air cleaner/filter in place
when driving.
Cooling System
The cooling system allows the
engine to maintain the correct
working temperature.
1. Coolant Surge Tank
2. Coolant Surge TankPressure Cap
3. Engine Electric Cooling Fan(s)
{Warning
An underhood electric fan can
start up even when the engine is
not running and can cause injury.
Keep hands, clothing, and tools
away from any underhood
electric fan.
{Warning
Do not touch heater or radiator
hoses, or other engine parts.
They can be very hot and can
burn you. Do not run the engine if
there is a leak; all coolant could
leak out. That could cause an
engine fire and can burn you. Fix
any leak before driving the
vehicle.
Engine Coolant
The cooling system in the vehicle is
filled with DEX-COOL engine
coolant. This coolant is designed to
remain in the vehicle for 5 years or
240 000 km (150,000 mi), whichever
occurs first.
The following explains the cooling
system and how to check and add
coolant when it is low. If there is a
problem with engine overheating,
see Engine Overheating 0300.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Vehicle Care 301
If Steam is Coming from the
Engine Compartment
{Warning
Steam and scalding liquids from a
hot cooling system are under
pressure. Turning the pressure
cap, even a little, can cause them
to come out at high speed and
you could be burned. Never turn
the cap when the cooling system,
including the pressure cap, is hot.
Wait for the cooling system and
pressure cap to cool.
If No Steam is Coming from
the Engine Compartment
The ENGINE OVERHEATED STOP
ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message, along with a low coolant
condition, can indicate a serious
problem.If there is an engine overheat
warning, but no steam is seen or
heard, the problem may not be too
serious. Sometimes the engine can
get a little too hot when the vehicle:
.
Climbs a long hill on a hot day.
. Stops after high-speed driving.
. Idles for long periods in traffic.
. Tows a trailer; see Trailer Towing
0 264.
If the ENGINE OVERHEATED
STOP ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message appears with no sign of
steam, try this for a minute or so: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the
highest fan speed. Open the
windows as necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or
N (Neutral), and let the
engine idle. If the engine coolant temperature
gauge is no longer in the overheat
zone or an overheat warning no
longer displays, the vehicle can be
driven. Continue to drive the vehicle
slowly for about 10 minutes. Keep a
safe vehicle distance from the
vehicle in front. If the warning does
not come back on, continue to drive
normally and have the cooling
system checked for proper fill and
function.
If the warning continues, pull over,
stop, and park the vehicle
right away.
If there is still no sign of steam and
the vehicle is equipped with an
engine driven cooling fan, push
down the accelerator until the
engine speed is about twice as fast
as normal idle speed for at least
five minutes while the vehicle is
parked. If the warning is still there,
turn off the engine and get everyone
out of the vehicle until it cools down.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
302 Vehicle Care
If there is no sign of steam, idle the
engine for five minutes while
parked. If the warning is still
displayed, turn off the engine until it
cools down.
Engine Fan
If the vehicle has electric cooling
fans, the fans may be heard
spinning at low speed during most
everyday driving. The fans may turn
off if no cooling is required. Under
heavy vehicle loading, trailer towing,
high outside temperatures,
or operation of the air conditioning
system, the fans may change to
high speed and an increase in fan
noise may be heard. This is normal
and indicates that the cooling
system is functioning properly. The
fans will change to low speed when
additional cooling is no longer
required.
The electric engine cooling fans
may run after the engine has been
turned. off. This is normal and no
service is required.
Washer Fluid
What to Use
When windshield washer fluid needs
to be added, be sure to read the
manufacturer's instructions before
use. Use a fluid that has sufficient
protection against freezing in an
area where the temperature may fall
below freezing.
Adding Washer Fluid
The vehicle has a low washer fluid
message on the DIC that comes on
when the washer fluid is low. The
message is displayed for
15 seconds at the start of each
ignition cycle. When the WASHER
FLUID LOW ADD FLUID message
displays, washer fluid will need to
be added to the windshield washer
fluid reservoir.
Open the cap with the washer
symbol on it. Add washer fluid until
the tank is full. SeeEngine
Compartment Overview 0286 for
reservoir location.
Caution
. Do not use washer fluid that
contains any type of water
repellent coating. This can
cause the wiper blades to
chatter or skip.
. Do not use engine coolant
(antifreeze) in the
windshield washer. It can
damage the windshield
washer system and paint.
. Do not mix water with
ready-to-use washer fluid.
Water can cause the
solution to freeze and
damage the washer fluid
tank and other parts of the
washer system.
(Continued)