2021 GMC YUKON tow

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Driving and Operating 303
Custom Checklist Items
For each of the Trailer Profile checklists,
there is an option to create custom items to
view in the checklist. The custom item will
appear at the bottom of the checklist.
Guest Trailer and No Trailer Connected
If Guest Trailer Profile is active or if no
trailer is connected, the checklist will show
all of the checklists associated with Custom
Trailer Profiles in addition to default
checklists.
Trailers View
Touch the Trailers tab to view, activate,
create, edit, or delete Trailer Profiles.
If a trailer is connected, touch the Trailer
Profile name to activate a Trailer Profile.
There can be up to five Custom Trailer
Profiles on the vehicle.
The Custom Trailer Profiles and Guest Trailer
are in order of the most frequently used.
The Accessory/No Trailer profile is shown
below the Custom Trailer Profiles and Guest
Trailer Profile.All personalization features are based on the
settings for each driver in vehicle
personalization. The list of Trailer Profiles is
based on vehicle personalization settings.
Guest Trailer
If the Guest Trailer Profile is the active
Trailer Profile, trailer detection, connections
status, theft, and the Tow/Haul reminder
alerts can be sent. The system will not track
total mileage or fuel economy, but the
system will track trip mileage and fuel
economy if the Guest Trailer Profile is active.
The Trailer Tire Pressure Monitoring System
or maintenance reminders cannot be set up
for a Guest Trailer Profile. The Guest Trailer
Profile cannot be edited.
Touch
pto learn more about the Guest
Trailer option.
Accessory/No Trailer
If the Accessory/No Trailer Profile is active,
alerts will not be sent and the system will
not track mileage or fuel economy. The
Trailer Tire Pressure Monitoring System or
maintenance reminders cannot be set up for
the Accessory/No Trailer Profile. The
Accessory/No Trailer profile cannot be
edited. No Trailer Connected
When there is no trailer connected, Trailer
Profiles cannot be activated but most
options can be edited.
Trailer Brake Gain Memory
The system can memorize the brake gain
setting of a Trailer Profile or a Guest Trailer
Profile. When a Trailer Profile or Guest
Trailer Profile is selected, and a brake gain
setting is set for that Trailer Profile, a quick
notice will appear to indicate that the
system has recalled that profile’s brake gain
setting.
If a Trailer Profile is already active and the
brake gain setting had been set for that
Trailer Profile, the quick notice will trigger
whenever the ignition is turned on.
If there was an error in setting the brake
gain for a Trailer Profile, there will be a
notification. This pop-up will not appear if
the Guest Trailer Profile is active or if there
is no trailer connected.
Trailer brake gain should be set for a specific
trailering condition and must be adjusted
anytime vehicle loading, trailer loading,
or road surface conditions change.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
304 Driving and Operating
Editing a Trailer Profile
Trailer Profile View
Touch to edit any of the following options
in the Trailer Profile view:
.Trailer Name
.Towing Assistance Setup, if equipped
.Tire Pressure Setup, if equipped
.Trailer Maintenance
.Edit Mileage
.Reset Average Fuel Economy
Touch Save to save the new value to the
Trailer Profile. Touching Back will still save
the previously entered information.
Trailer Name
Touch to edit the Trailer Profile’s name. Use
at least one character and no spaces.
Touch Save.
Towing Assistance Setup
A trailer should be connected to complete
this portion of profile setup.
Touch to set up towing assistance features
for the Trailer Profile. See "Towing
Assistance" for details on the setup. Tire Pressure Setup
Touch to set up the Trailer Tire Pressure
Monitoring System (TTPMS) for the Trailer
Profile. See
“Trailer Tire Pressure Setup”
previously in this section for details on the
setup. Also, touch Tire Pressure Setup if the
trailer tires were rotated or if the tire
pressure sensors in the tires were replaced
for this Trailer Profile. The vehicle will need
to relearn the tire sensors and their
locations.
If TTPMS had been set up previously, the
Select Number of Sensors screen will appear
after touching Tire Pressure Setup. If the
number of sensors has changed, select the
number and touch Next.
If a new number of sensors is selected, the
Relearn Sensors pop-up will appear. Touch
Cancel to go back or touch Relearn to
overwrite the current sensors and begin the
relearning process. See “Trailer Tire Pressure
Setup” previously in this section.
If number of sensors has not changed, touch
Next and the Learn sensors screen will
appear. On the Learn Sensors screen. Touch Relearn
to overwrite the current sensors and begin
the relearning process. See
“Trailer Tire
Pressure Setup” previously in this section.
On the Learn Sensors screen, touch Next to
go to the Edit Recommended Tire Pressure
screen.
On the Edit Recommended Tire Pressure
screen, touch a number on the keypad to
change the
Recommended Tire Pressure for the trailer’s
tires. This will change the number at which
the vehicle displays alerts related to trailer
tire pressure. Touch Done to return to the
Trailer Profile view.
Trailer Maintenance
Touch to view a list of maintenance
reminders for the Trailer Profile.
Touch a reminder to view, reset, delete,
or edit it.
Reset Reminder
Touch Maintenance Complete in the
reminder view to reset the reminder. On the
pop-up, touch Reset to reset the time and
mileage values for the reminder. Touch
Cancel to return to the previous view and
nothing will change.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Driving and Operating 305
Edit Reminder
Touch to edit the mileage or time settings
for the reminder. Touch Save to save the
new settings to the Trailer Profile.
Delete Reminder
Touch to delete the maintenance reminder.
On the pop-up, touch Delete to delete the
reminder or touch Cancel to return to the
previous view and nothing will change.
New Maintenance Reminder
Touch + New Maintenance Reminder to set
up a new reminder. Suggested reminders
that were previously set will have
checkmarks next to them. Suggested
reminders that have not been set will have
empty boxes next to them. The maximum
number of reminders is 50.
Edit Mileage
Touch to edit the Trailer Profile’s mileage.
Touch Reset to reset trailer mileage to zero,
or enter a new value and touch Save.
Touching back will return to the Trailer
Profile view.Effect on Maintenance Reminders
If the mileage is reset or changed, and
mileage has already accumulated, any
maintenance reminders that have been set
up will be adjusted accordingly.
Reset Average Fuel Economy
Touch to reset the average fuel economy for
the Trailer Profile. Touch Reset to change,
or touch Cancel to go back to the
previous view.
Delete/Remove Trailer
Touch to remove the Trailer Profile and all
of its settings.
On the pop-up, touch Remove to remove the
Trailer Profile from the vehicle. Touch Cancel
to dismiss the pop-up and return to the
previous view.
Remove will be displayed if there is a
connected OnStar plan active with the
vehicle. Removing a trailer profile will
remove the profile from the vehicle but the
profile will still be associated with the user
account. However, if there is not a
connected OnStar plan then the remove
button will read DELETE and the profile will
be deleted permanentlySettings View
Within the Trailering App, touch the Settings
tab to modify the following settings:
.Trailer Detection Alert
.Maintenance Alerts
.Theft Alert
.Tow/Haul Mode Reminder
Trailer Detection Alert
The Trailer Detection Alert setting will be on
by default. Turn it off to disable the Trailer
Detection pop-up from displaying when a
trailer is connected. The Guest Trailer Profile
will become the active Trailer Profile, unless
another Trailer Profile is selected manually
through the Trailering App. If this setting is
disabled while a Custom Trailer Profile is
active, that Trailer Profile will remain the
active profile until the trailer is
disconnected.
Maintenance Alerts
Touch Maintenance Alerts to view the
Maintenance Alerts settings page. These
alerts are based on the Trailer Profile, so the
settings for each Trailer Profile must be
turned on or off. Touch a profile to view
more information or adjust the setting for
that profile.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
306 Driving and Operating
The setting will be on by default for each
profile. All Maintenance Alerts for that active
Trailer Profile will be received.
Turn a setting off to not receive any of the
Maintenance Alerts when that Trailer Profile
is active.
Theft Alert
A theft alert can be set if a trailer is
connected and the alert is enabled. When
the trailer is disconnected and the vehicle is
off, an alarm will sound.
Touch Theft Alert in Settings to view the
Theft Alert settings page. These alerts are
based on the Trailer Profile, so the settings
for each Trailer Profile must be turned on or
off. Touch a profile to view more
information or adjust the setting for that
profile.
This setting will be off by default for each
Trailer Profile, including the Guest Trailer
Profile.
A smartphone will receive a notification that
the trailer related to the selected Trailer
Profile is disconnected from the vehicle,
if the setting is on for the active Trailer
Profile, the vehicle has an OnStar orconnected service plan and the smartphone
number has been added to the account for
this notification.
If the setting is turned off for a given Trailer
Profile, the smartphone will not receive this
security notification even if the Trailer
Profile is active.Tow/Haul Mode Reminder
This is a reminder to turn on the Tow/Haul
Mode when towing a trailer. See
Tow/Haul
Mode 0235.
Touch Tow/Haul Mode Reminder in Settings
to view the Tow/Haul Mode Reminder
settings page. These alerts are based on the
Trailer Profile, so the settings for each
Trailer Profile must be turned on or off.
Touch a profile to view more information or
to adjust the setting for that profile.
This setting will default to OFF for each
Trailer Profile, including the Guest Trailer
Profile.
If Tow/Haul Mode is off and this setting is
on for a Trailer Profile, each time the
ignition is turned on a reminder will appear
to turn on Tow/Haul Mode when the Trailer
Profile is active. If Tow/Haul Mode is on and this setting is
on for a Trailer Profile, the reminder will not
appear when the Trailer Profile is active.
Conversions and Add-Ons
Add-On Electrical Equipment
{Warning
The Data Link Connector (DLC) is used for
vehicle service and Emission Inspection/
Maintenance testing. See
Malfunction
Indicator Lamp (Check Engine Light) 0111.
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.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
308 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . 309
California Proposition 65 Warning . . . . . 309
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . 309
Accessories and Modifications . . . . . . . . . 309
Vehicle Checks
Doing Your Own Service Work . . . . . . . . . 310
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Engine Compartment Overview . . . . . . . . 312
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315
Engine Oil Life System . . . . . . . . . . . . . . . . . 316
Automatic Transmission Fluid . . . . . . . . . . 317
Engine Air Filter Life System . . . . . . . . . . . 318
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . 318
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 319
Engine Overheating . . . . . . . . . . . . . . . . . . . . 322
Engine Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 324
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324
Brake Pad Life System . . . . . . . . . . . . . . . . . 325
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 326
Battery - North America . . . . . . . . . . . . . . . 327
Four-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . 327
Front Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328
Rear Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328 Park Brake and P (Park) Mechanism
Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328
Wiper Blade Replacement . . . . . . . . . . . . . 329
Glass Replacement . . . . . . . . . . . . . . . . . . . . 330
Windshield Replacement . . . . . . . . . . . . . . 330
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 331
Bulb Replacement
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
Electrical System
Electrical System Overload . . . . . . . . . . . . . 331
Fuses and Circuit Breakers . . . . . . . . . . . . . 331
Engine Compartment Fuse Block . . . . . . . 332
Instrument Panel Fuse Block . . . . . . . . . . . 335
Rear Compartment Fuse Block . . . . . . . . . 337
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . 340
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 340
Low-Profile Tires . . . . . . . . . . . . . . . . . . . . . . 340
All-Terrain Tires . . . . . . . . . . . . . . . . . . . . . . . 340
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . . 341
Tire Designations . . . . . . . . . . . . . . . . . . . . . . 342
Tire Terminology and Definitions . . . . . . 342
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 344
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 345 Tire Pressure Monitor System . . . . . . . . . 346
Tire Pressure Monitor Operation . . . . . . . 347
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . 349
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . 350
When It Is Time for New Tires . . . . . . . . . 351
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . 351
Different Size Tires and Wheels . . . . . . . . 352
Uniform Tire Quality Grading . . . . . . . . . . 353
Wheel Alignment and Tire Balance . . . . 354
Wheel Replacement . . . . . . . . . . . . . . . . . . . 354
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 355
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . 356
Full-Size Spare Tire . . . . . . . . . . . . . . . . . . . . 366
Jump Starting
Jump Starting - North America . . . . . . . . 367
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . . . . . . . . . . 370
Recreational Vehicle Towing . . . . . . . . . . . 371
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . 374
Interior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 378
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 381

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
310 Vehicle Care
Also, seeAdding Equipment to the
Airbag-Equipped Vehicle 069.
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 0406.
This vehicle has an airbag system. Before
attempting to do your own service work,
see Servicing the Airbag-Equipped Vehicle
0 69. If equipped with remote vehicle start, open
the hood before performing any service
work to prevent remote starting the vehicle
accidentally. See
Remote Vehicle Start 014.
Keep a record with all parts receipts and list
the mileage and the date of any service
work performed. See Maintenance Records
0 395.Caution
Even small amounts of contamination can
cause damage to vehicle systems. Do not
allow contaminants to contact the fluids,
reservoir caps, or dipsticks.
Hood
{Warning
For vehicles with auto engine stop/start,
turn the vehicle off before opening the
hood. If the vehicle is on, the engine will
start when the hood is opened. You or
others could be injured.
{Warning
Components under the hood can get hot
from running the engine. To help avoid
the risk of burning unprotected skin,
never touch these components until they
have cooled, and always use a glove or
towel to avoid direct skin contact.
Clear any snow from the hood before
opening.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Vehicle Care 315
11. Windshield Washer Fluid Reservoir. See“Adding Washer Fluid” underWasher
Fluid 0324.
Engine Oil
For diesel engine vehicles, see “Engine Oil”
in the Duramax diesel supplement.
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. SeeEngine Oil Life System 0316.
.Always dispose of engine oil properly. See
“What to Do with Used Oil” in this
section.
Checking Engine Oil
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 0312 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.
If a low oil Driver Information Center (DIC)
message displays, check the oil level.
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 engine
oil level on steep grades or too soon after
engine shutoff can result in incorrect
readings. Accuracy improves when
checking a cold engine prior to starting.
Remove the dipstick and check the level.
.If unable to wait two hours, the engine
must be off for at least 15 minutes if the
engine is warm, or at least 30 minutes if
the engine is not warm. Pull out the dipstick, wipe it with a clean paper towel
or cloth, then push it back in all the way.
Remove it again, keeping the tip down,
and check the level.
When to Add Engine Oil
If the oil is below the cross-hatched area at
the tip of the dipstick and the engine has
been off for at least 15 minutes, add 1 L (1
qt) of the recommended oil and then
recheck the level. See
“Selecting the Right
Engine Oil” later in this section for an
explanation of what kind of oil to use. For
engine oil crankcase capacity, see Capacities
and Specifications 0396.
Caution
Do not add too much oil. Oil levels above
or below the acceptable operating range
shown on the dipstick are harmful to the
engine. If the oil level is above the
operating range (i.e., the engine has so
(Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Vehicle Care 323
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.
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; seeTrailer Towing0284.
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.
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.