2021 GMC YUKON brake life

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Instruments and Controls 121
Speed :Shows the vehicle speed in either
kilometers per hour (km/h) or miles per
hour (mph). The vehicle odometer is also
shown on this page. If equipped, press the
thumbwheel to open the menu and select to
display speed limit signs.
Trip 1 or Trip 2, and Average Fuel
Economy : Shows the current distance
traveled, in either kilometers (km) or
miles (mi), since the trip odometer was last
reset.
The Average Fuel Economy display shows
the approximate average liters per
100 kilometers (L/100 km), kilometers per
liter (km/L), or miles per gallon (mpg). This
number is calculated based on the value
recorded since the last time this menu item
was reset. This number reflects only the
approximate average fuel economy that the
vehicle has right now, and will change as
driving conditions change.
Press the thumbwheel while this display is
active to reset the trip odometer and the
average fuel economy.
Fuel Range : Shows the approximate
distance the vehicle can be driven without
refueling. LOW will be displayed when the
vehicle is low on fuel. The fuel range
estimate is based on an average of the vehicle's fuel economy over recent driving
history and the amount of fuel remaining in
the fuel tank.
Timer :
This display can be used as a timer.
To start the timer, press the thumbwheel
while this display is active. The display will
show the amount of time that has passed
since the timer was last reset. To stop the
timer, press the thumbwheel briefly while
this display is active and the timer is
running.
Press the thumbwheel while this display is
active to reset the timer.
Oil Life : Shows an estimate of the oil's
remaining useful life. If REMAINING OIL LIFE
99% is displayed, that means 99% of the
current oil life remains.
When the remaining oil life is low, the
CHANGE ENGINE OIL SOON message will
appear on the display. The oil should be
changed as soon as possible. See Engine Oil
0 315. In addition to the engine oil life
system monitoring the oil life, additional
maintenance is recommended. See
Maintenance Schedule 0384.
The Oil Life display must be reset after each
oil change. It will not reset itself. Do not
reset the Oil Life display at any time other than when the oil has just been changed.
It cannot be reset accurately until the next
oil change. To reset the engine oil life
system, press the thumbwheel while the Oil
Life display is active. See
Engine Oil Life
System 0316.
Tire Pressure : Shows the approximate
pressures of all four tires. Tire pressure is
displayed in either kilopascal (kPa) or in
pounds per square inch (psi). If the pressure
is low, the value for that tire is shown in
amber. See Tire Pressure Monitor System
0 346 and
Tire Pressure Monitor Operation 0347.
Air Filter Life : Shows an estimate of the
engine air filter’s remaining useful life and
the state of the system. Engine Air Filter Life
95% means 95% of the current air filter life
remains. Messages will display based on the
engine air filter life and the state of the
system. When the REPLACE SOON message
displays, the engine air filter should be
replaced at the earliest convenience.
The Air Filter Life display must be reset after
the engine air filter replacement. To reset,
see Engine Air Filter Life System 0318.
Brake Pad Life : This displays an estimate of
the remaining life of the front and rear
brake pads. Messages will display based on

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
122 Instruments and Controls
brake pad wear and the state of the system.
Reset the Brake Pad Life display after
replacing the brake pads. SeeBrake Pad Life
System 0325.
Fuel Economy : Displays average fuel
economy, the best fuel economy over the
selected distance, and a bar graph showing
instantaneous fuel economy.
Press the thumbwheel to change the
selected distance. Press and hold the
thumbwheel while this display is active to
reset the best fuel economy and average
fuel economy. This display can also be reset
by selecting reset in the menu.
Engine Hours (Hourmeter) : Shows the total
number of hours the engine has run. This
display also shows the engine idle hours.
Transmission Fluid Temperature : Shows the
temperature of the automatic transmission
fluid in either degrees Celsius (°C) or degrees
Fahrenheit (°F).
Trailer Brake : On vehicles with the
Integrated Trailer Brake Control (ITBC)
system, the trailer brake display appears in
the DIC. TRAILER GAIN shows the trailer gain setting.
This setting can be adjusted from 0.0 to 10.0
with either a trailer connected or
disconnected.
OUTPUT shows the power output to the
trailer any time a trailer with electric brakes
is connected. Output is displayed as a bar
graph. Dotted lines may appear in the
OUTPUT display if a trailer is not connected.
Off Road :
If equipped, displays vehicle pitch
and roll information, road wheel angle, and
four-wheel drive (4WD) status.
Follow Distance : If equipped, the current
follow time to the vehicle ahead is displayed
as a time value on this page.
Driver Assistance : If equipped, shows
information for Lane Keep Assist (LKA) and
Forward Collision Alert (FCA).
Info Page Options : Scroll to choose which
info pages appear on the DIC. Press the
thumbwheel to select or deselect.
Blank Page : Shows no information.Head-Up Display (HUD)
{Warning
If the HUD image is too bright or too
high in your field of view, it may take
you more time to see things you need to
see when it is dark outside. Be sure to
keep the HUD image dim and placed low
in your field of view.
If equipped with HUD, some information
about the operation of the vehicle is
projected onto the windshield. The image is
projected through the HUD lens on top of
the instrument panel. The information
appears as an image focused out toward the
front of the vehicle.
Caution
If you try to use the HUD image as a
parking aid, you may misjudge the
distance and damage your vehicle. Do not
use the HUD image as a parking aid.
The HUD information can be displayed in
various languages. The speedometer reading
and other numerical values can be displayed
in either English or metric units.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Driving and Operating 217
Loading the Vehicle for Off-Road Driving
{Warning
.Unsecured cargo on the load floor can
be tossed about when driving over
rough terrain. You or your passengers
can be struck by flying objects. Secure
the cargo properly.
.Keep cargo in the cargo area as far
forward and as low as possible. The
heaviest things should be on the floor,
forward of the rear axle.
.Heavy loads on the roof raise the
vehicle's center of gravity, making it
more likely to roll over. You can be
seriously or fatally injured if the
vehicle rolls over. Put heavy loads
inside the cargo area, not on the roof.
For more information about loading the
vehicle, see Vehicle Load Limits 0222 and
Tires 0339.
Environmental Concerns
.Always use established trails, roads, and
areas that have been set aside for public
off-road recreational driving and obey all
posted regulations.
.Do not damage shrubs, flowers, trees,
or grasses or disturb wildlife.
.Do not park over things that burn. See
Parking over Things That Burn 0231.
Driving on Hills
Driving safely on hills requires good
judgment and an understanding of what the
vehicle can and cannot do.
{Warning
Many hills are simply too steep for any
vehicle. Driving up hills can cause the
vehicle to stall. Driving down hills can
cause loss of control. Driving across hills
can cause a rollover. You could be injured
or killed. Do not drive on steep hills.
Before driving on a hill, assess the
steepness, traction, and obstructions. If the
terrain ahead cannot be seen, get out of the
vehicle and walk the hill before driving
further.
When driving on hills:
.Use a low gear and keep a firm grip on
the steering wheel.
.Maintain a slow speed.
.When possible, drive straight up or down
the hill.
.Slow down when approaching the top of
the hill.
.Use headlamps even during the day to
make the vehicle more visible.
{Warning
Driving to the top of a hill at high speed
can cause a crash. There could be a
drop-off, embankment, cliff, or even
another vehicle. You could be seriously
injured or killed. As you near the top of a
hill, slow down and stay alert.
.Never go downhill forward or backward
with either the transmission or transfer
case in N (Neutral). The brakes could
overheat and you could lose control.
{Warning
If the vehicle has the two-speed
automatic or electronic transfer case,
shifting the transfer case to N (Neutral)
can cause your vehicle to roll even if the
transmission is in P (Park). This is because
the N (Neutral) position on the transfer (Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
236 Driving and Operating
hills or mountain grades, when towing,
or when hauling heavy loads. SeeDriver
Mode Control 0245 to activate Tow/
Haul Mode.
Tow/Haul Mode Grade Braking
Tow/Haul Mode Grade Braking is only
enabled while the Tow/Haul Mode is
selected and the vehicle is not in the Range
Selection Mode. See Manual Mode0235.
Tow/Haul Mode Grade Braking assists in
maintaining desired vehicle speeds when
driving on downhill grades by using the
engine and transmission to slow the vehicle.
See Towing Equipment 0287.
Drive Systems
Four-Wheel Drive
If equipped, four-wheel drive engages the
front axle for extra traction.
Read the appropriate section for transfer
case operation before using.
Caution
Do not drive on clean, dry pavement in 4
mand 4n(if equipped) for an extended
period of time. These conditions may
cause premature wear on the vehicle’s
powertrain.
Driving on clean, dry pavement in 4
mor 4
nmay:
.Cause a vibration to be felt in the
steering system.
.Cause tires to wear faster.
{Warning
If equipped with four-wheel drive, the
vehicle will be free to roll if the transfer
case is in N (Neutral), even when the
transmission is in P (Park). You or
someone else could be seriously injured.
Be sure the transfer case is in a drive
gear —2
m, 4m, or 4n—or set the
parking brake before placing the transfer
case in N (Neutral). See Shifting Into Park
0 230.
Caution
Extended high-speed operation in 4n
may damage or shorten the life of the
drivetrain.
An engagement noise and bump is normal
when shifting between 4
nand 4mor
N (Neutral), with the engine running.
Shifting into 4
nwill turn Traction Control
and StabiliTrak/Electronic Stability Control
(ESC) off. See Traction Control/Electronic
Stability Control 0242.
Automatic Transfer Case
Two-Speed Transfer Case

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Driving and Operating 241
Before leaving the vehicle, check the red
parking brake status light to ensure that the
parking brake is applied.
EPB Apply
To apply the EPB:1. Be sure the vehicle is at a complete stop.
2. Press the EPB switch momentarily.
The red parking brake status light will flash
and then stay on once the EPB is fully
applied. If the red parking brake status light
flashes continuously, then the EPB is only
partially applied or there is a problem with
the EPB. A DIC message will display. Release
the EPB and try to apply it again. If the
light does not come on, or keeps flashing,
have the vehicle serviced. Do not drive the
vehicle if the red parking brake status light
is flashing. See your dealer.
If the amber service parking brake warning
light is on, press the EPB switch. Continue to
hold the switch until the red parking brake
status light remains on. If the amber service
parking brake warning light is on, see your
dealer. If the EPB is applied while the vehicle is
moving, the vehicle will decelerate as long
as the switch is pressed. If the switch is
pressed until the vehicle comes to a stop,
the EPB will remain applied.
The vehicle may automatically apply the EPB
in some situations when the vehicle is not
moving. This is normal, and is done to
periodically check the correct operation of
the EPB system, or at the request of other
safety functions that utilize the EPB.
If the EPB fails to apply, block the rear
wheels to prevent vehicle movement.
EPB Release
To release the EPB:
1. Turn the ignition on or to ACC/ ACCESSORY.
2. Apply and hold the brake pedal.
3. Press the EPB switch momentarily.
The EPB is released when the red parking
brake status light is off.
If the amber service parking brake warning
light is on, release the EPB by pressing and
holding the EPB switch. Continue to hold the
switch until the red parking brake status
light is off. If either light stays on after
release is attempted, see your dealer.
Caution
Driving with the parking brake on can
overheat the brake system and cause
premature wear or damage to brake
system parts. Make sure that the parking
brake is fully released and the brake
warning light is off before driving.
If you are towing a trailer and parking on a
hill, see Driving Characteristics and Towing
Tips 0280.
Automatic EPB Release
The EPB will automatically release if the
vehicle is running, placed into gear, and an
attempt is made to drive away. Avoid rapid
acceleration when the EPB is applied, to
preserve parking brake lining life.
Brake Assist
Brake Assist detects rapid brake pedal
applications due to emergency braking
situations and provides additional braking to
activate the Antilock Brake System (ABS) if
the brake pedal is not pushed hard enough
to activate ABS normally. Minor noise, brake
pedal pulsation, and/or pedal movement
during this time may occur. Continue to

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
Vehicle Care 325
{Warning
The brake wear warning sound means
that soon the brakes will not work well.
That could lead to a crash. When the
brake wear warning sound is heard, have
the vehicle serviced.
Caution
Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates can
cause a brake squeal when the brakes are
first applied or lightly applied. This does not
mean something is wrong with the brakes.
Properly torqued wheel nuts are necessary
to help prevent brake pulsation. When tires
are rotated, inspect brake pads for wear and
evenly tighten wheel nuts in the proper
sequence to torque specifications in
Capacities and Specifications 0396.
Brake linings should always be replaced as
complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not
return to normal height, or if there is a
rapid increase in pedal travel. This could be
a sign that brake service may be required.
Replacing Brake System Parts
Always replace brake system parts with
new, approved replacement parts. If this is
not done, the brakes may not work
properly. The braking performance expected
can change in many other ways if the
wrong replacement brake parts are installed
or parts are improperly installed.
Brake Pad Life System
When to Change Brake Pads
This vehicle has a system that estimates the
remaining life of the front and rear brake
pads. Brake pad life is displayed in the
Driver Information Center (DIC), along with
a percentage for each axle. The system must
be reset every time the brake pads are
changed.
When the system has determined that the
brake pads need to be replaced, a message
will display, which may include mileage
remaining. Brake pads should always be replaced as
complete axle sets.
How to Reset the Brake Pad Life System
The system will automatically detect when
significantly worn brake pads are replaced.
When the ignition is turned on after new
pads and wear sensors are installed, a
message will display. Follow the prompts to
reset the system.
The brake pad life system can also be
manually reset:
1. Display Brake Pad Life on the DIC. See Driver Information Center (DIC) 0120.
2. Press the thumbwheel or the trip odometer reset stem if the vehicle does
not have DIC buttons. Select front or rear
pads as appropriate.
3. Select YES on the confirmation message, or press the trip odometer reset stem on
a base level DIC. Repeat for pads on the
other axle if they were also replaced.
How to Disable the Brake Pad Life
System
The brake pad life system can be turned off.
This may be necessary if aftermarket brake
pads without wear sensors are installed.
When the system is turned off, the front

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
326 Vehicle Care
and rear brake pad life percentages will not
display. However, the built-in wear
indicators that make a high-pitched warning
sound when the brake pads are worn can
still determine when the pads should be
replaced. SeeBrakes0324.
To turn off the brake pad life system: 1. Display Brake Pad Life on the DIC. See Driver Information Center (DIC) 0120.
2. Select DISABLE.
To turn the brake pad life system back on,
follow the above steps but select ENABLE in
Step 2.
Brake Fluid
The brake master cylinder reservoir is filled
with GM approved DOT 4 brake fluid as
indicated on the reservoir cap. See Engine
Compartment Overview 0312 for the
location of the reservoir. 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.
{Warning
If 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 0112.
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 0384.
What to Add
Use only GM approved DOT 4 brake fluid
from a clean, sealed container. See
Recommended Fluids and Lubricants 0392.
{Warning
The wrong or contaminated brake fluid
could result in damage to the brake
system. This could result in the loss of
(Continued)