GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-15883563) - 2022 - CRC - 11/19/21
228 Driving and Operating
pulling it toward you. If you can, it means
that the shift lever was not fully locked into
P (Park).
Torque Lock
If you are parking on a hill and you do not
shift the transmission into P (Park) properly,
the weight of the vehicle may put too much
force on the parking pawl in the
transmission. You may find it difficult to pull
the shift lever out of P (Park). This is called
torque lock. To prevent torque lock, set the
parking brake and then shift into P (Park)
properly before you leave the driver seat.
When you are ready to drive, move the
shift lever out of P (Park) before you release
the parking brake.
If torque lock does occur, you may need to
have another vehicle push yours a little
uphill to take some of the pressure from the
parking pawl in the transmission. You will
then be able to pull the shift lever out of
P (Park).
Shifting Into Park (Electronic
Shifter)
{Warning
It can be dangerous to get out of the
vehicle if the shift lever is not fully in
P (Park) with the parking brake firmly set.
The vehicle can roll. If you have left the
engine running, the vehicle can move
suddenly. You or others could be injured.
To be sure the vehicle will not move,
even when you are on fairly level ground,
use the steps that follow. With
four-wheel drive, if the transfer case is in
N (Neutral), the vehicle will be free to
roll, even if the shift lever is in P (Park).
Be sure the transfer case is in a drive
gear. If towing a trailer, seeDriving
Characteristics and Towing Tips 0309.
1. Hold the brake pedal down and set the parking brake. See Electric Parking Brake
0 245.
2. Press the P (Park) switch on the top of the shift lever. See Automatic
Transmission (Mechanical Shifter) 0231
or Automatic Transmission (Electronic
Shifter) 0233. 3. The P indicator on the shift lever will
turn red when the vehicle is in P (Park).
If the vehicle is shifted into P (Park) on a
hill, the Electric Parking Brake (EPB) may
apply automatically. The driver may not be
able to release the EPB using the EPB
switch. It should automatically release when
the vehicle is shifted out of P (Park).
Leaving the Vehicle with the Engine
Running
{Warning
It can be dangerous to leave the vehicle
with the engine running. It could
overheat and catch fire.
It is dangerous to get out of the vehicle
if the vehicle is not in P (Park) with the
parking brake set. The vehicle can roll.
Do not leave the vehicle when the engine
is running. If you have left the engine
running, the vehicle can move suddenly.
You or others could be injured. To be
sure the vehicle will not move, even
when you are on fairly level ground,
always set the parking brake and shift to (Continued)
GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Driving and Operating 231
Warning (Continued)
.There are holes or openings in the
vehicle body from damage or
aftermarket modifications that are not
completely sealed.
If unusual fumes are detected or if it is
suspected that exhaust is coming into the
vehicle:
.Drive it only with the windows
completely down.
.Have the vehicle repaired immediately.
Never park the vehicle with the engine
running in an enclosed area such as a
garage or a building that has no fresh air
ventilation.
Running the Vehicle While Parked
It is better not to park with the engine
running.
If the vehicle is left with the engine running,
follow the proper steps to be sure the
vehicle will not move. See Shifting Into Park
(Mechanical Shifter) 0227 orShifting Into
Park (Electronic Shifter) 0228 and Engine
Exhaust 0230. If parking on a hill and pulling a trailer, see
Driving Characteristics and Towing Tips
0
309.
Automatic Transmission
Automatic Transmission
(Mechanical Shifter)
There is an electronic shift lever position
indicator within the instrument cluster. This
display illuminates when the vehicle is on.
There are several different positions for the
shift lever.
See Driver Mode Control 0249 and “Range
Selection Mode” underManual Mode
(Mechanical Shifter) 0237 or
Manual Mode (Electronic Shifter) 0239.
P : This position locks the rear wheels. Use
P (Park) when starting the engine because
the vehicle cannot move easily. When parked on a hill, especially when the
vehicle has a heavy load, you might notice
an increase in the effort to shift out of
P (Park). See
“Torque Lock” underShifting
Into Park (Mechanical Shifter) 0227 or
Shifting Into Park (Electronic Shifter) 0228.
{Warning
It is dangerous to get out of the vehicle
if the shift lever is not fully in P (Park)
with the parking brake firmly set. The
vehicle can roll.
Do not leave the vehicle when the engine
is running. If you have left the engine
running, the vehicle can move suddenly.
You or others could be injured. To be
sure the vehicle will not move, even
when you are on fairly level ground,
always set the parking brake and move
the shift lever to P (Park). See Shifting
Into Park (Mechanical Shifter) 0227 or
Shifting Into Park (Electronic Shifter)
0 228 and Driving Characteristics and
Towing Tips 0309.
GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-15883563) - 2022 - CRC - 11/19/21
242 Driving and Operating
The settings are:
N (Neutral) :Use only when the vehicle
needs to be towed. See Recreational Vehicle
Towing 0411 orTowing the Vehicle 0409.
2
m(Two-Wheel Drive High) : Use for driving
on most streets and highways. The front
axle is not engaged. This setting provides
the best fuel economy.
AUTO (Automatic Four-Wheel Drive) : Use
when road surface conditions are variable.
When driving in AUTO, the front axle is
engaged, and the vehicle's power is sent to
the front and rear wheels automatically
based on driving conditions. This setting
provides slightly lower fuel economy
than 2
m.
4
m(Four-Wheel Drive High) : Use this
setting when extra traction is needed, such
as when driving on snowy or icy roads,
when off-roading, or when plowing snow.
4
n(Four-Wheel Drive Low) : This setting
engages the front axle and delivers extra
torque. Choose 4
nwhen driving off-road in
deep sand, deep mud, or deep snow, and
while climbing or descending steep hills.
While driving in 4
n, keep vehicle speed
below 72 km/h (45 mph). Shifting into 4
nwill turn Traction Control
and StabiliTrak/ESC off. See Traction Control/
Electronic Stability Control 0247.
Shifts between 2
m, 4m, and AUTO
Any of these shifts can be made at normal
driving speed.
The actual 4x4 shift request is only made
after the button is released. The 4x4 graphic
will remain flashing until the shift request
has completed. A DIC message displays to
indicate that the 4x4 transfer case has been
requested to shift to the new desired state.
Once the 4x4 shift has completed, the DIC
message disappears, the 4x4 graphic stops
flashing, and the current setting is indicated.
When a shift to 2
mis completed successfully
while in P (Park), the parking brake will
engage. To resume driving, shift the
transmission to the desired gear and
manually release the parking brake or press
the accelerator pedal to begin driving. See
Electric Parking Brake 0245.
If equipped, use 4
n, AUTO, or 4mto provide
additional traction when parking on a steep
grade with poor traction such as ice, snow,
mud, or gravel. Shifting Into 4
n
1. The ignition must be on and the vehicle
must be stopped or moving less than
5 km/h (3 mph) with the transmission in
N (Neutral). It is best for the vehicle to
be moving 1.6 to 3.2 km/h (1 to 2 mph).
2. Press 4
n. The actual 4x4 shift request is
only made after the button is released.
The 4x4 graphic will remain flashing
until the shift request has completed.
A DIC message displays to indicate that
the 4x4 transfer case has been requested
to shift to the new desired state.
Once the 4x4 shift has completed, the
DIC message disappears, the 4x4 graphic
stops flashing and the current setting is
indicated.
If vehicle speed is higher when shift request
occurs, a DIC message displays. Reduce
vehicle speed.
If the transmission is not in N (Neutral)
when shift request occurs, a DIC message
displays. The vehicle will allow 20 seconds
for the shift to occur. After this time, a
graphic in the instrument cluster will
indicate that the transfer case is in 4
n.
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Driving and Operating 251
For more information on trailer weight
specifications, seeTrailer Towing0313.
gTerrain Mode : Use for finer control
during low speed, off-road driving. When
using this mode it will mimic the
characteristics of four-wheel-drive low (4
n)
without the torque capabilities.
Use when:
.Traveling on very rough roads at very low
speeds, such as a two-track or heavily
rutted road.
.Traveling slowly in grassy fields.
.Pulling a boat out of the water on a
trailer.
.Using the vehicle for public off-road
recreational driving. See Off-Road Driving
0 208 and Hill and Mountain Roads
0 213. Using terrain mode in extreme conditions
that cause the wheel(s) to slip can lead to
excessive heat in the transfer case causing
four-wheel drive and terrain mode to
automatically turn off, leaving the vehicle in
two-wheel drive. Four-wheel drive will
automatically re-engage once the transfer
case has cooled, then terrain mode can be
turned back on.
When in Terrain Mode, the vehicle will shift
automatically but may hold a lower gear
longer to maximize engine torque. A unique
pedal map, transmission shift pattern, and
rpm control are utilized to give better
control at lower speeds and over rough
terrain. When the vehicle comes to a stop,
Vehicle Hold is engaged. TCS will be
optimized for maximum torque transfer
across axles, and Active Braking During Lift
Throttle will be engaged. Active Braking During Lift Throttle:
.Automatically applies light braking,
similar to heavy engine braking of
four-wheel-drive low.
.Applies light braking in D (Drive) until the
vehicle is at idle speeds. In Manual L1 and
Manual L2, moderate braking may stop
the vehicle.
.Reduces trailer braking.
GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-15883563) - 2022 - CRC - 11/19/21
252 Driving and Operating
Terrain Mode DriveSelect Expected Vehicle Behavior Ideal Terrain
Drive (L3-Lx) Minor deceleration when off
throttle and mild ability to
modulate throttle; mimics
performance of 4
nwithout torque
multiplication. Grassy fields,
mild two tracks,
rutted roads,
large rolling hills
L2 Moderate deceleration when off
throttle and moderate ability to
modulate throttle; will bring vehicle
to a stop in most cases. Mild rock crawling,
heavy ruts,
short, steeper grades
L1 Significant deceleration when off
throttle and significant ability to
modulate throttle; will bring vehicle
to a stop in most cases. Rock crawling downhill
Active Braking During Lift Throttle will
reduce the back and forth between the
accelerator and brake pedals.
Vehicle Hold Features:
.When the vehicle comes to a stop on an
incline grade in forward gear or on a
decline grade in reverse gear, Vehicle
Hold is engaged until the accelerator
pedal is pressed.
.When the vehicle is in forward gear on a
decline, the vehicle is allowed to creep
down the hill when the brake pedal is
released without pressing the accelerator
pedal. The vehicle will also creep forward
on flat ground.
.If the driver seat belt is removed and the
driver door is opened while the vehicle is
being held, Electric Parking Brake (EPB)
will be engaged.
.EPB will engage if the vehicle is held for
an extended period.
Terrain Mode is only available on vehicles
equipped with the single speed
transfer case.
Terrain Mode can only be active when:
.Vehicle speed is less than 80 km/h
(50 mph).
.The transfer case is in 4m.
Frequent use of this mode may cause brake
wear due to the light braking.
The vehicle will automatically exit the mode
if the brakes get too hot. Terrain Mode can
be turned back on after the brakes have
cooled.
When Terrain Mode is selected:
.Auto Engine Start/Stop will be disabled.
.The Terrain Mode indicator displays on
the instrument cluster.
Limited-Slip Differential
If equipped, the limited-slip differential 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 allows the drive wheel with the
most traction to move the vehicle. For
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Driving and Operating 253
vehicles with the limited-slip differential,
driven under severe conditions, the rear axle
fluid should be changed. SeeMaintenance
Schedule 0425.
Locking Rear Axle
If equipped, the locking rear axle can give
the vehicle additional traction from the rear
wheels when traveling in off-road situations
such as mud, snow, steep hills, and uneven
terrain.
Caution
Do not lock the axle while the tires are
spinning. The vehicle drivetrain could be
damaged. The repairs would not be
covered by the vehicle warranty.
Caution
If the vehicle’s axle is locked while driving
on pavement, the drivetrain could be
damaged. Repairs would not be covered
by the vehicle warranty. Do not use the
locking axle on pavement.
Before the front axle can be locked, the rear
axle must be locked and the transfer case
must be in 4
n.
To lock the rear axle: 1. The vehicle must be stationary.
2. Press and release the rear axle locking switch.
3. Wait for the light in the switch to stop flashing and remain illuminated to show
that the rear axle is locked. The locking rear axle will be disengaged
when the vehicle speed exceeds 40 km/h
(25 mph). The Off-Road Mode allows the axle
lock to remain engaged at higher vehicle
speeds.
After pressing the switch to unlock the axle,
it may remain locked due to torque in the
driveline. The axle is more easily unlocked
by turning the steering wheel to the right
and to the left while traveling at a low
speed.
Locking Front Axle
If equipped, the locking front axle can give
the vehicle additional traction when
traveling in off-road situations such as mud,
snow, steep hills, and uneven terrain.
GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-15883563) - 2022 - CRC - 11/19/21
254 Driving and Operating
Caution
Do not lock the axle while the tires are
spinning. The vehicle drivetrain could be
damaged. The repairs would not be
covered by the vehicle warranty.
Caution
If the vehicle’s axle is locked while driving
on pavement, the drivetrain could be
damaged. Repairs would not be covered
by the vehicle warranty. Do not use the
locking axle on pavement.
Before the front axle can be locked, the
transfer case must be in 4
n. The front axle cannot be locked
independently of the rear axle.
To lock the front and rear axles:
1. Place the transfer case in 4
n. This is the
only mode that allows the front axle to
lock. See Four-Wheel Drive 0240 for
more information regarding the transfer
case and four-wheel drive low operation.
2. Press the front/rear axle locking switch with the vehicle stopped.
3. Wait for the light in the switch to stop flashing and remain illuminated to show
that the front axle is locked. Engagement
of the front axle lock will disable the
Antilock Brake System (ABS) and
illuminate the ABS warning light. Hill
Descent Control (HDC) will also be
disabled.
The locking front axle will be disengaged
when the vehicle speed exceeds 40 km/h
(25 mph) or the transfer case is shifted out
of 4
n.
ABS will be automatically re-enabled and the
ABS warning light will turn off when the
locking front axle is disengaged. If HDC was enabled prior to axle lock, it will
be automatically enabled when the locking
front axle is disengaged.
After pressing the switch to unlock the axle,
it may remain locked due to torque in the
driveline. The axle is more easily unlocked
by turning the steering wheel to the right
and to the left while traveling at a low
speed.
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.
GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Driving and Operating 327
If the CHECK TRAILER WIRING message only
reappears when connecting the trailer wiring
harness to the vehicle, the electrical fault is
on the trailer side.
SERVICE TRAILER BRAKE SYSTEM: This
message will display when there is a
problem with the ITBC system. If this
message continues over multiple ignition
cycles, have the vehicle serviced.
If either the CHECK TRAILER WIRING or
SERVICE TRAILER BRAKE SYSTEM message
displays while driving, the ITBC system may
not be fully functional or may not function
at all. When traffic conditions allow,
carefully pull the vehicle over to the side of
the road and turn the ignition off. Check the
wiring connection to the trailer and turn the
ignition back on. If either of these messages
continues, either the vehicle or trailer needs
service.
A GM dealer may be able to diagnose and
repair problems with the trailer. However,
any diagnosis and repair of the trailer is not
covered under the vehicle warranty. Contact
your trailer dealer for assistance with trailer
repairs and trailer warranty information.Trailer Sway Control (TSC)
Vehicles with StabiliTrak/Electronic Stability
Control (ESC) have a Trailer Sway Control
(TSC) feature. Trailer sway is unintended
side-to-side motion of a trailer while towing.
If the vehicle is towing a trailer and the TSC
detects that sway is increasing, the vehicle
brakes are selectively applied at each wheel,
to help reduce excessive trailer sway.
If equipped with the Integrated Trailer Brake
Control (ITBC) system, and the trailer has an
electric brake system, StabiliTrak/ESC may
also apply the trailer brakes.
If TSC is enabled, the Traction Control
System (TCS)/StabiliTrak/ESC warning light
will flash on the instrument cluster. Reducevehicle speed by gradually removing your
foot from the accelerator. If trailer sway
continues, StabiliTrak/ESC can reduce engine
torque to help slow the vehicle. TSC will not
function if StabiliTrak/ESC is turned off. See
Traction Control/Electronic Stability Control
0
247.
{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,
unrestrained cargo, improper trailer hitch
configuration, or improperly inflated or
incorrect vehicle or trailer tires. See
Towing Equipment 0317 for trailer
ratings and hitch setup recommendations.