traction control GMC YUKON 2021 Owner's Guide

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Driving and Operating 243
comes on, and the appropriate message will
appear on the Driver Information
Center (DIC).
The indicator light for both systems is in the
instrument cluster. This light will:
.Flash when TCS is limiting wheel spin.
.Flash when StabiliTrak/ESC is activated.
.Turn on and stay on when either system
is not working. SeeTraction Control
System (TCS)/Electronic Stability Control
Light 0115.
If either system fails to turn on or to
activate, a message displays in the DIC, and
dcomes on and stays on to indicate that
the system is inactive and is not assisting
the driver in maintaining control. Without
the assistance of properly functioning
StabiliTrak/ESC the possibility of rollover is
increased. Adjust driving accordingly.
If
dcomes on and stays on:
1. Stop the vehicle. 2. Turn the engine off and wait 15 seconds.
3. Start the engine.
Drive the vehicle. If
dcomes on and stays
on, see your dealer.
Turning the Systems Off and On
The button for TCS and StabiliTrak/ESC is on
the instrument panel to the left of the
steering wheel.
Caution
Do not repeatedly brake or accelerate
heavily when TCS is off. The vehicle
driveline could be damaged. To turn off only TCS, press and release
g.
The traction off light
idisplays in the
instrument cluster. The appropriate message
will display in the DIC. To turn TCS on again,
press and release
g. The traction off light
idisplayed in the instrument cluster will
turn off.
If TCS is limiting wheel spin when
gis
pressed, the system will not turn off until
the wheels stop spinning.
To turn off both TCS and StabiliTrak/ESC,
press and hold
guntil the traction off light
iand the StabiliTrak OFF lightgcome on
and stay on in the instrument cluster, then
release. The appropriate message will
display in the DIC.
To turn TCS and StabiliTrak/ESC on again,
press and release
g. The traction off light
iand the StabiliTrak OFF lightgin the
instrument cluster turn off.
For vehicles without four corner air
suspension StabiliTrak/ESC will automatically
turn on if the vehicle exceeds 56 km/h
(35 mph). Traction control will remain off.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
246 Driving and Operating
6Snow/Ice Mode :Snow/Ice improves
vehicle acceleration on snow and ice covered
roads. When active, Snow/Ice Mode will
adjust acceleration to optimize traction on
slippery surfaces. This can compromise the
acceleration on dry asphalt. This feature is
not intended for use when the vehicle is
stuck in sand, mud, ice, snow, or gravel.
If the vehicle becomes stuck see If the
Vehicle Is Stuck 0221.
7Off-Road Mode : Use this mode for
off-road recreational driving. Off-Road Mode
should be used to improve driving at
moderate speeds, on grass, gravel, dirt,
unpaved roads, or snow-covered roads. The
accelerator pedal is tuned for off-road use.
This mode modifies pedal mapping, AWD,
steering, ride height, ABS, ESC, and TCS
performance. For more information on
off-road driving, see Off-Road Driving0216.
_Tow/Haul Mode : For more
information on Tow/Haul Mode, see Tow/
Haul Mode 0235.
If equipped, select Terrain Mode by pressing
the
gbelow the 4mtransfer case
button.
gTerrain Mode : Use this mode when
traveling on very rough roads at very low
speeds, such as a two-track or heavily rutted
road. This can also be used for pulling a
boat out of the water on a trailer. When in
Terrain Mode, the vehicle will shift
automatically but will hold a lower gear
longer to maximize engine torque. This
mode has a unique pedal map and
transmission shift pattern for better control
at lower speeds and over rough terrain. This
mode modifies accelerator pedal mapping, transmission shift pattern, ride height,
suspension, steering, AWD, eSLD, ESC
performance and TCS performance.
When the vehicle comes to a stop on an
upward grade, Automatic Vehicle Hold is
engaged until the driver presses the
accelerator pedal. Stop/Start and cruise
control are disabled in Terrain Mode.
Active Braking during lift throttle will be
engaged. This feature automatically applies
light braking to simulate heavy engine
braking of four-wheel-dive low. It also
applies light braking in D (Drive) until the
vehicle is at idle speeds. In M1 and M2 light
braking will typically bring the vehicle to a
stop. Active Braking during lift throttle will
also reduce trailer braking.
Terrain Mode will automatically exit to
Normal Mode if the brake temperatures
become too hot, electronic parking brake
becomes inoperable or the vehicle cannot
perform braking or vehicle hold.
For more information on off-road driving,
see
Off-Road Driving 0216 and
Hill and Mountain Roads 0220.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
248 Driving and Operating
Locking Rear Axle
Vehicles with a locking rear axle can give
more traction on snow, mud, ice, sand,
or gravel. It works like a standard axle most
of the time, but when traction is low, this
feature will allow the rear wheel with the
most traction to move the vehicle.
Four Corner Air Suspension
System
The Four Corner Air Suspension feature
provides full time load leveling capability
along with the benefit of adjusting ride
height for increased convenience and
capability.
{Warning
To help avoid personal injury or death,
make sure the area underneath the
vehicle and inside the wheel wells is clear
when lowering the vehicle.
{Warning
To help avoid personal injury or death,
always select the lowest ride height for
the current driving conditions. Higher ride
heights raise the vehicle's center of
gravity, increasing the chance of a
rollover during extreme maneuvers.
{Warning
Heavy loads on the roof rack will make
the vehicle's center of gravity higher,
increasing the possibility of a rollover. To
avoid losing control of the vehicle, always
select the normal height setting and
avoid high speeds, sudden starts, sharp
turns, sudden braking, or abrupt
maneuvers when carrying cargo on the
roof rack.Changing Ride Height
Press the Ride Height button to open the
Ride Height Menu on the Instrument Panel.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Driving and Operating 251
Air Suspension Service
If a‘Service Leveling System’ message is
displayed in the instrument cluster, see your
authorized dealer immediately.
Cruise Control
{
Warning
Cruise control can be dangerous where
you cannot drive safely at a steady
speed. Do not use cruise control on
winding roads or in heavy traffic.
Cruise control can be dangerous on
slippery roads. On such roads, fast
changes in tire traction can cause
excessive wheel slip, and you could lose
control. Do not use cruise control on
slippery roads.
If equipped with cruise control, a speed of
about 40 km/h (25 mph) or more can be
maintained without keeping your foot on
the accelerator. Cruise control does not work
at speeds below about 40 km/h (25 mph).
If the cruise control is being used and the
Traction Control System (TCS) or StabiliTrak/
Electronic Stability Control (ESC) begins to
limit wheel spin, the cruise control will automatically disengage. See
Traction
Control/Electronic Stability Control 0242.
If a collision alert occurs when cruise control
is activated, cruise control is disengaged. See
Forward Collision Alert (FCA) System 0267.
When road conditions allow you to safely
use it again, cruise control can be turned
back on.
Turning off the TCS or StabiliTrak/ESC
system will disengage the cruise control.
If the brakes are applied, cruise control
disengages.
5: Press to turn cruise control on or off.
A white indicator comes on or off in the
instrument cluster. +RES :
If there is a set speed in memory,
press the control up briefly to resume to
that speed or press and hold to accelerate.
If cruise control is already engaged, use to
increase vehicle speed.
SET− :Press the control down briefly to set
the speed and activate cruise control.
If cruise control is already engaged, use to
decrease vehicle speed.
*: Press to disengage cruise control
without erasing the set speed from memory.
Setting Cruise Control
If
5is on when not in use, SET− or +RES
could get pressed and go into cruise when
not desired. Keep
5off when cruise is not
being used.
1. Press
5to turn the cruise system on.
2. Get up to the desired speed.
3. Press and release SET−.
4. Remove your foot from the accelerator.
The cruise control indicator on the
instrument cluster turns green after cruise
control has been set to the desired speed.
See Instrument Cluster 0104.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Driving and Operating 253
Adaptive Cruise Control
(Advanced)
If equipped with Adaptive Cruise Control
(ACC), it allows for selecting the cruise
control set speed and following gap. Read
this entire section before using this system.
ACC uses a camera and radar sensor(s) to
detect other vehicles. SeeRadio Frequency
Statement 0407.
The following gap is the following time (or
distance) between your vehicle and a vehicle
detected directly ahead in your path,
moving in the same direction. If no vehicle
is detected in your path, ACC works like
regular cruise control.
If a vehicle is detected in your path, ACC can
apply acceleration or limited, moderate
braking to maintain the selected following
gap. To disengage ACC, apply the brake.
If ACC is controlling the vehicle speed when
the Traction Control System (TCS) or
StabiliTrak/Electronic Stability Control (ESC)
system activates, ACC may automatically
disengage. See Traction Control/Electronic
Stability Control 0242. When road
conditions allow ACC to be safely used, ACC
can be turned back on. Disabling the TCS or StabiliTrak/ESC system
will disengage and prevent engagement
of ACC.
ACC can reduce the need for you to
frequently brake and accelerate, especially
when used on expressways, freeways, and
interstate highways. When used on other
roads, you may need to take over the
control of braking or acceleration more
often.
{Warning
ACC has limited braking ability and may
not have time to slow the vehicle down
enough to avoid a collision with another
vehicle you are following. This can occur
when vehicles suddenly slow or stop
ahead, or enter your lane. Also see
“Alerting the Driver”
later in this section.
Complete attention is always required
while driving and you should be ready to
take action and apply the brakes. See
Defensive Driving 0214.
{Warning
ACC will not detect or brake for children,
pedestrians, animals, or other objects.
Do not use ACC when:
.On winding and hilly roads or when
the camera sensor is blocked by snow,
ice, or dirt. The system may not
detect a vehicle ahead. Keep the
windshield and headlamps clean.
.When visibility is poor due to rain,
snow, fog, dirt, insect residue, or dust;
when other foreign objects obscure
the camera’s view; or when the
vehicle in front or oncoming traffic
causes additional environmental
obstructions, such as road spray. ACC
performance is limited under these
conditions.
.On slippery roads where fast changes
in tire traction can cause excessive
wheel slip
.With extremely heavy cargo loaded in
the cargo area or rear seat
.When towing a trailer

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
258 Driving and Operating
Irregular Objects Affecting ACC
ACC may have difficulty detecting the
following objects:
.Vehicles with cargo extending from the
back end.
.Non-standard shaped vehicles, such as
vehicle transport, vehicles with a side car
fitted, or horse carriages.
.Objects that are close to the front of your
vehicle.
ACC Automatically Disengages
ACC may automatically disengage and the
driver will need to manually apply the
brakes to slow the vehicle if:
.The sensors are blocked.
.The Traction Control System (TCS) or
StabiliTrak/ESC system has activated or
been disabled.
.There is a fault in the system.
.The radar falsely reports blockage when
driving in a desert or remote area with
no other vehicles or roadside objects.
A DIC message may display to indicate
that ACC is temporarily unavailable.
The ACC indicator will turn white when ACC
is no longer active. In some cases, when ACC is temporarily
unavailable, regular cruise control may be
used. See
“Switching Between ACC and
Regular Cruise Control” previously in this
section. Always consider driving conditions
before using either cruise control system.
Notification to Resume ACC
ACC will maintain a follow gap behind a
detected vehicle and slow your vehicle to a
stop behind that vehicle.
If the stopped vehicle ahead has driven
away and ACC has not resumed, the vehicle
ahead indicator will flash as a reminder to
check traffic ahead before proceeding. In
addition, the left and right sides of the
Safety Alert Seat will pulse three times,
or three beeps will sound. See ”Alert Type”
and “Adaptive Cruise Go Notifier” in
“Collision/Detection Systems” underVehicle
Personalization 0126.
When the vehicle ahead drives away, press
RES+ or the accelerator pedal to resume
ACC. If stopped for more than two minutes
or if the driver door is opened and the
driver seat belt is unbuckled, the ACC
automatically applies the Electric Parking
Brake (EPB) to hold the vehicle. The EPB
status light will turn on. See Electric Parking
Brake 0240. A DIC warning message may display
indicating to shift to P (Park) before exiting
the vehicle. See
Vehicle Messages 0125.
{Warning
If ACC has stopped the vehicle, and if ACC
is disengaged, turned off, or canceled, the
vehicle will no longer be held at a stop.
The vehicle can move. When ACC is
holding the vehicle at a stop, always be
prepared to manually apply the brakes.
{Warning
Leaving the vehicle without placing it in
P (Park) can be dangerous. Do not leave
the vehicle while it is being held at a
stop by ACC. Always place the vehicle in
P (Park) and turn off the ignition before
leaving the vehicle.
ACC Override
If using the accelerator pedal while ACC is
active, the ACC indicator turns blue on the
instrument cluster indicating ACC braking
will not occur. ACC will resume operation
when the accelerator pedal is not being
pressed.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
296 Driving and Operating
If TSC is enabled, the Traction Control
System (TCS)/StabiliTrak warning light will
flash on the instrument cluster. Reduce
vehicle speed by gradually removing your
foot from the accelerator. If trailer sway
continues, StabiliTrak can reduce engine
torque to help slow the vehicle. TSC will not
function if StabiliTrak is turned off. See
Traction Control/Electronic Stability Control
0242.
{Warning
Trailer sway can result in a crash and in
serious injury or death, even if the
vehicle is equipped with TSC.
If the trailer begins to sway, reduce
vehicle speed by gradually removing your
foot from the accelerator. Then pull over
to check the trailer and vehicle to help
correct possible causes, including an
improperly or overloaded trailer,
(Continued)
Warning (Continued)
unrestrained cargo, improper trailer hitch
configuration, or improperly inflated or
incorrect vehicle or trailer tires. See
Towing Equipment0287 for trailer
ratings and hitch setup recommendations.
Aftermarket Electronic Trailer Sway
Control Devices
Some trailers may come equipped with an
electronic device designed to reduce or
control trailer sway. Aftermarket equipment
manufacturers also offer similar devices that
connect to the wiring between the trailer
and the vehicle. These devices may interfere
with the vehicle’s trailer brake systems or
other systems, including integrated
anti-sway systems, if equipped. Messages
related to trailer connections or trailer
brakes could appear on the DIC. The effects
of these aftermarket devices on vehicle
handling or trailer brake performance is not
known.
{Warning
Use of aftermarket electronic trailer sway
control devices could result in reduced
trailer brake performance, loss of trailer
brakes, or other malfunctions, and result
in a crash. You or others could be
seriously injured or killed. Before using
one of these devices:
.Ask the device or trailer manufacturer
if the device has been thoroughly
tested for compatibility with the
make, model, and year of your vehicle
and any optional equipment installed
on your vehicle.
.Before driving, check the trailer brakes
are working properly, if equipped.
Drive the vehicle with the trailer
attached on a level road surface that
is free of traffic at about 32-40 km/h
(20-25 mph) and fully apply the
manual trailer brake apply lever. Also,
check the trailer brake lamps and
other lamps are functioning correctly.
.If the trailer brakes are not operating
properly at any time, or if a DIC
message indicates problems with the
trailer connections or trailer brakes, (Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Vehicle Care 309
General Information
For service and parts needs, visit your
dealer. You will receive genuine GM parts
and GM-trained and supported service
people.
Genuine GM parts have one of these marks:
California Proposition 65 Warning
{Warning
Most motor vehicles, including this one,
as well as many of its service parts and
fluids, contain and/or emit chemicals
known to the State of California to cause(Continued)
Warning (Continued)
cancer and birth defects or other
reproductive harm. Engine exhaust, many
parts and systems, many fluids, and
some component wear by-products
contain and/or emit these chemicals. For
more information go to
www.P65Warnings.ca.gov/
passenger-vehicle.
See Battery - North America 0327 and
Jump Starting - North America 0367 and
the back cover.
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.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Vehicle Care 351
{Warning
Do not apply grease to the wheel
mounting surface, wheel conical
seats, or the wheel nuts or bolts.
Grease applied to these areas could
cause a wheel to become loose or
come off, resulting in a crash.
When It Is Time for New Tires
Factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road
conditions affect the wear rate of the tires.
Treadwear indicators are one way to tell
when it is time for new tires. Treadwear
indicators appear when the tires have only 1.6 mm (1/16 in) or less of tread remaining.
See
Tire Inspection 0349 and
Tire Rotation 0350 for additional
information.
The rubber in tires ages over time. This also
applies to the spare tire, if the vehicle has
one, even if it is never used. Multiple factors
including temperatures, loading conditions,
and inflation pressure maintenance affect
how fast aging takes place. GM recommends
that tires, including the spare if equipped,
be replaced after six years, regardless of
tread wear. To identify the age of a tire, use
the tire manufacture date, which is the last
four digits of the DOT Tire Identification
Number (TIN) molded into one side of the
tire sidewall. The last four digits of the TIN
indicate the tire manufactured date. The
first two digits represent the week and the
last two digits, the year. For example, the
third week of the year 2020 would have a
4-digit DOT date of 0320. Week 01 is the
first full week (Sunday through Saturday) of
each year.
Vehicle Storage
Tires age when stored normally mounted on
a parked vehicle. Park a vehicle that will be
stored for at least a month in a cool, dry,
clean area away from direct sunlight to slow aging. This area should be free of grease,
gasoline, or other substances that can
deteriorate rubber.
Parking for an extended period can cause
flat spots on the tires that may result in
vibrations while driving. When storing a
vehicle for at least a month, remove the
tires or raise the vehicle to reduce the
weight from the tires.
Buying New Tires
GM has developed and matched specific
tires for the vehicle. The original
equipment tires installed were designed
to meet General Motors Tire
Performance Criteria Specification (TPC
Spec) system rating. When replacement
tires are needed, GM strongly
recommends buying tires with the same
TPC Spec rating.
GM's exclusive TPC Spec system
considers over a dozen critical
specifications that impact the overall
performance of the vehicle, including
brake system performance, ride and
handling, traction control, and tire
pressure monitoring performance. GM's

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
352 Vehicle Care
TPC Spec number is molded onto the
tire's sidewall near the tire size. If the
tires have an all-season tread design,
the TPC Spec number will be followed
by MS for mud and snow. SeeTire
Sidewall Labeling 0341 for additional
information.
GM recommends replacing worn tires in
complete sets of four. Uniform tread
depth on all tires will help to maintain
the performance of the vehicle. Braking
and handling performance may be
adversely affected if all the tires are not
replaced at the same time. If proper
rotation and maintenance have been
done, all four tires should wear out at
about the same time. However, if it is
necessary to replace only one axle set
of worn tires, place the new tires on
the rear axle. See Tire Rotation0350.
{Warning
Tires could explode during improper
service. Attempting to mount or
dismount a tire could cause injury or
(Continued)
Warning (Continued)
death. Only your dealer or authorized
tire service center should mount or
dismount the tires.
{Warning
Mixing tires of different sizes (other
than those originally installed on the
vehicle), brands, tread patterns,
or types may cause loss of vehicle
control, resulting in a crash or other
vehicle damage. Use the correct size,
brand, and type of tire on all wheels.
{Warning
Using bias-ply tires on the vehicle
may cause the wheel rim flanges to
develop cracks after many miles of
driving. A tire and/or wheel could fail
suddenly and cause a crash. Use only
radial-ply tires with the wheels on
the vehicle. Winter tires with the same speed rating
as the original equipment tires may not
be available for H, V, W, Y and ZR
speed rated tires. Never exceed the
winter tires’
maximum speed capability
when using winter tires with a lower
speed rating.
If the vehicle tires must be replaced
with a tire that does not have a TPC
Spec number, make sure they are the
same size, load range, speed rating, and
construction (radial) as the original
tires.
The Tire and Loading Information label
indicates the original equipment tires
on the vehicle. See Vehicle Load Limits
0 222.
Different Size Tires and Wheels
If wheels or tires are installed that are a
different size than the original equipment
wheels and tires, vehicle performance,
including its braking, ride and handling
characteristics, stability, and resistance to
rollover may be affected. If the vehicle has
electronic systems such as antilock brakes,
rollover airbags, traction control, electronic