2021 GMC CANYON automatic transmission

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
14430430) - 2021 - CRC - 9/9/20
192 Driving and Operating
Engine Exhaust{
Warning
Engine exhaust contains carbon monoxide
(CO), which cannot be seen or smelled.
Exposure to CO can cause
unconsciousness and even death.
Exhaust may enter the vehicle if:
.The vehicle idles in areas with poor
ventilation (parking garages, tunnels,
deep snow that may block underbody
airflow or tail pipes).
.The exhaust smells or sounds strange
or different.
.The exhaust system leaks due to
corrosion or damage.
.The vehicle exhaust system has been
modified, damaged, or improperly
repaired.
.There are holes or openings in the
vehicle body from damage or
aftermarket modifications that are not
completely sealed. (Continued)
Warning (Continued)
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
0 190 and
Engine Exhaust 0192.
If parking on a hill and pulling a trailer, see
Driving Characteristics and Towing Tips
0 217.
Automatic Transmission
If equipped, there is an electronic shift lever
position indicator within the instrument
cluster. This display comes on when the
ignition key is in ACC/ACCESSORY or
ON/RUN.
P : This position locks the drive 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
0 190.

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
14430430) - 2021 - CRC - 9/9/20
Driving and Operating 193
{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). SeeShifting
Into Park 0190 and
Driving Characteristics and Towing Tips
0 217.
{Warning
If you have four-wheel drive, the vehicle
will be free to roll —even if the shift
lever is in P (Park) —if the transfer case
is in N (Neutral). So, be sure the transfer
case is in a drive gear, Two-Wheel Drive (Continued)
Warning (Continued)
High or Four-Wheel Drive High or
Four-Wheel Drive Low—not in
N (Neutral). See Shifting Into Park 0190.
R : Use this gear to back up.
Caution
Shifting to R (Reverse) while the vehicle is
moving forward could damage the
transmission. The repairs would not be
covered by the vehicle warranty. Shift to
R (Reverse) only after the vehicle is
stopped.
To rock the vehicle back and forth to get
out of snow, ice, or sand without damaging
the transmission, see If the Vehicle Is Stuck
0 179.
N : In this position, the engine does not
connect with the wheels. To restart the
engine when the vehicle is already moving,
use N (Neutral) only.
{Warning
Shifting into a drive gear while the
engine is running at high speed is
dangerous. Unless your foot is firmly on
the brake pedal, the vehicle could move
very rapidly. You could lose control and
hit people or objects. Do not shift into a
drive gear while the engine is running at
high speed.
Caution
Shifting out of P (Park) or N (Neutral) with
the engine running at high speed may
damage the transmission. The repairs
would not be covered by the vehicle
warranty. Be sure the engine is not
running at high speed when shifting the
vehicle.
Caution
A transmission hot message may display
if the automatic transmission fluid is too
hot. Driving under this condition can
damage the vehicle. Stop and idle the
engine to cool the automatic
(Continued)

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
14430430) - 2021 - CRC - 9/9/20
Driving and Operating 195
Manual Mode
Range Selection Mode
Range Selection Mode helps control the
vehicle's transmission and vehicle speed
while driving downhill or towing a trailer by
letting you select a desired range of gears.To use this feature:
1. Move the shift lever to L (Manual Mode).
2. Press the plus/minus button on the shift lever to select the desired range of gears
for current driving conditions.
When the shift lever is moved from
D (Drive) to L (Manual Mode), a number
displays next to the L, indicating the current
transmission range.
This number is the highest gear that the
transmission will command while operating
in L (Manual Mode). All gears below that
number are available. As driving conditions
change, the transmission can automatically
shift to lower gears. For example, when L5 is
selected, 1 (First) through 5 (Fifth) gears are
automatically shifted by the transmission,
but 6 (Sixth) cannot be used until the plus/
minus button on the shift lever is used to
change to the range. When the shift lever is moved from
D (Drive) to L (Manual Mode), a downshift
may occur. The gear that the transmission is
operating in when the shift lever is moved
from D (Drive) to L (Manual Mode)
determines if a downshift occurs. See the
following chart.

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
14430430) - 2021 - CRC - 9/9/20
196 Driving and Operating
6-Speed Automatic TransmissionGear before shifting from D (Drive) to
L (Manual Mode) 6th 5th 4th 3rd 2nd 1st
Range after shifting from D (Drive) to
L (Manual Mode) L4 L4 L3 L2 L2 L1
8-Speed Automatic Transmission Gear before shifting
from D (Drive) to
L (Manual Mode) 8th 7th 6th 5th 4th 3rd 2nd 1st
Range after shifting
from D (Drive) to
L (Manual Mode) –
Tow/Haul not engaged L6 L6 L5 L4 L3 L3 L2 L1
Range after shifting
from D (Drive) to
L (Manual Mode) –
Tow/Haul engaged L6 L5 L4 L3 L3 L3 L2 L1
Grade Braking is not available when Range
Selection Mode is active. See Tow/Haul
Mode 0196. While using Range Selection Mode, cruise
control and the Tow/Haul Mode can
be used.Caution
Spinning the tires or holding the vehicle
in one place on a hill using only the
accelerator pedal may damage the
transmission. The repair will not be
covered by the vehicle warranty. If the
vehicle is stuck, do not spin the tires.
When stopping on a hill, use the brakes
to hold the vehicle in place.
Low Traction Mode
If equipped, Low Traction Mode assists in
vehicle acceleration when road conditions
are slippery, such as with ice or snow. While
the vehicle is at a stop, select L2 using
Range Selection Mode. This will limit torque
to the wheels and help to prevent the tires
from spinning.
Tow/Haul Mode
If equipped, Tow/Haul Mode adjusts the
transmission shift pattern to reduce shift
cycling. While towing heavy loads, this
mode provides increased performance and
vehicle control.

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
14430430) - 2021 - CRC - 9/9/20
200 Driving and Operating
4. Turn the transfer case knob to 2m.
After the transfer case has shifted out of
N (Neutral), the N (Neutral) light will
go out.
5. Release the parking brake.
Caution
Shifting the transmission into gear before
the requested mode indicator light has
stopped flashing could damage the
transfer case.
6. Start the engine and shift the transmission to the desired gear.
Automatic Transfer Case
Use the transfer case knob next to the
steering wheel to shift into and out of
four-wheel drive.
All of the lights will flash on then off
momentarily when the ignition is turned on.
The light that remains on will indicate the
state of the transfer case.
If the indicator mark on the knob does not
match up with the light then that likely
means the knob was moved when the
ignition was off.
The indicator mark on the knob must line
up with the indicator light before a shift can
be commanded. To command a shift rotate
the transfer case knob to the new desired
position. The light will flash meaning that
the shift is in progress. When the shift is
completed the new position will be
illuminated. If the transfer case cannot
complete a shift command, it will go back to
its last chosen setting.
The settings are:
N (Neutral) : Use only when the vehicle
needs to be towed. See Recreational Vehicle
Towing 0297 or
Towing the Vehicle 0296. 2m(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 traction 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.
Do not use AUTO mode, if equipped, to park
on a steep grade with poor traction such as
ice, snow, mud, or gravel. In AUTO mode
only the rear wheels will hold the vehicle
from sliding when parked. If parking on a
steep grade, use 4
mto keep all four wheels
engaged.
4
m(Four-Wheel Drive High) : This setting
engages the front axle. Use this position
when extra traction is needed, such as when
driving on snowy or icy roads, or when
off-roading.

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
14430430) - 2021 - CRC - 9/9/20
Driving and Operating 217
Driving Characteristics and
Towing Tips
{Warning
You can lose control when towing a
trailer if the correct equipment is not
used or the vehicle is not driven properly.
For example, if the trailer is too heavy or
the trailer brakes are inadequate for the
load, the vehicle may not stop as
expected. You and others could be
seriously injured. The vehicle may also be
damaged, and the repairs would not be
covered by the vehicle warranty. Pull a
trailer only if all the steps in this section
have been followed. Ask your dealer for
advice and information about towing a
trailer with the vehicle.
Driving with a Trailer
Trailering is different than just driving the
vehicle by itself. Trailering means changes in
handling, acceleration, braking, durability,
and fuel economy. Successful, safe trailering
takes correct equipment, and it has to be
used properly.The following information has many
time-tested, important trailering tips and
safety rules. Many of these are important
for your safety and that of your passengers.
Read this section carefully before pulling a
trailer.
When towing a trailer:
.Become familiar with and follow all state
and local laws that apply to trailer
towing. These requirements vary from
state to state.
.State laws may require the use of
extended side view mirrors. Even if not
required, you should install extended side
view mirrors if your visibility is limited or
restricted while towing.
.Do not tow a trailer during the first
800 km (500 mi) of vehicle use to prevent
damage to the engine, axle, or other
parts.
.It is recommended to perform the first oil
change before heavy towing.
.During the first 800 km (500 mi) of trailer
towing, do not drive over 80 km/h
(50 mph) and do not make starts at full
throttle.
.Vehicles can tow in D (Drive). Tow/Haul
Mode is recommended for heavier trailers.
See
Tow/Haul Mode 0196. If the transmission downshifts too often, a
lower gear may be selected using Manual
Mode. See
Manual Mode 0195.
If equipped, the following driver assistance
features should be turned off when towing
a trailer:
.Adaptive Cruise Control (ACC)
.Super Cruise Control
.Lane Keep Assist (LKA)
.Park Assist
.Reverse Automatic Braking (RAB)
If equipped, the following driver assistance
features should be turned to alert or off
when towing a trailer:
.Automatic Emergency Braking (AEB)
.Intelligent Brake Assist (IBA)
.Front Pedestrian Braking (FPB)
If equipped with Lane Change Alert (LCA),
the LCA detection zones that extend back
from the side of the vehicle do not move
further back when a trailer is towed. Use
caution while changing lanes when towing a
trailer.
If equipped with Rear Cross Traffic Alert
(RCTA), use caution while backing up when
towing a trailer, as the RCTA detection zones

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
14430430) - 2021 - CRC - 9/9/20
220 Driving and Operating
Warning (Continued)
.Do not move the vehicle if someone is
in the path of the trailer. Some parts
of the trailer might be underwater and
not visible to people who are assisting
in launching the boat.
Disconnect the wiring to the trailer before
backing the trailer into the water to prevent
damage to the electrical circuits on the
trailer. Reconnect the wiring to the trailer
after removing the trailer from the water.
If the trailer has electric brakes that can
function when the trailer is submerged, it
might help to leave the electrical trailer
connector attached to maintain trailer brake
functionality while on the boat ramp.
To back the trailer into the water: 1. If equipped, place the vehicle in four-wheel-drive high.
2. Slowly back down the boat ramp until the boat is floating, but no further than
necessary.
3. Press and hold the brake pedal, but do not shift into P (Park) yet.
4. Have someone place chocks under the front wheels of the vehicle. 5. Gradually release the brake pedal to
allow the chocks to absorb the load of
the trailer.
6. Reapply the brake pedal. Then apply the parking brake and shift into P (Park).
7. Release the brake pedal.
Pulling the Trailer from the Water
To pull the trailer of the water: 1. Press and hold the brake pedals.
2. Start the engine and shift into gear.
3. Release the parking brake.
4. Let up on the brake pedal.
5. Drive slowly until the tires are clear of the chocks.
6. Stop and have someone pick up and store the chocks.
7. Slowly pull the trailer from the water.
8. Once the vehicle and trailer have been driven from the sloped part of the boat
ramp, the vehicle can be shifted from
four-wheel-drive high. Shift into the drive
mode that is appropriate for the road
conditions.
Caution
If the vehicle tires begin to spin and the
vehicle begins to slide toward the water,
remove your foot from the accelerator
pedal and apply the brake pedal. Seek
help to have the vehicle towed up
the ramp.
Maintenance when Trailer Towing
The vehicle needs service more often when
used to tow trailers. See Maintenance
Schedule 0310. It is especially important to
check the automatic transmission fluid,
engine oil, axle lubricant, belts, cooling
system, and brake system before and during
each trip.
Check periodically to see that all nuts and
bolts on the trailer hitch are tight.
Engine Cooling When Trailer Towing
The cooling system may temporarily
overheat during severe operating conditions.
See Engine Overheating 0247.
Trailer Towing
If equipped with a diesel engine, see the
Duramax diesel supplement.

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
14430430) - 2021 - CRC - 9/9/20
Driving and Operating 227
Turn Signals When Towing a Trailer
When properly connected, the trailer turn
signals will illuminate to indicate the vehicle
is turning, changing lanes, or stopping.
When towing a trailer, the arrows on the
instrument cluster will illuminate even if the
trailer is not properly connected or the bulbs
are burned out.
Tow/Haul Mode
For instructions on how to enter Tow/Haul
Mode, seeTow/Haul Mode 0196.
Tow/Haul assists when pulling a heavy
trailer or a large or heavy load.
Tow/Haul Mode is designed to be most
effective when the vehicle and trailer
combined weight is at least 75% of the
vehicle's Gross Combined Weight Rating
(GCWR). See “Weight of the Trailer” under
Trailer Towing 0220.
Tow/Haul Mode is most useful when towing
a heavy trailer or carrying a large or
heavy load:
.through rolling terrain.
.in stop-and-go traffic.
.in busy parking lots. Operating the vehicle in Tow/Haul Mode
when lightly loaded or not towing will not
cause damage; however, it is not
recommended and may result in unpleasant
engine and transmission driving
characteristics and reduced fuel economy.
Integrated Trailer Brake Control System
The vehicle may have an Integrated Trailer
Brake Control (ITBC) system for use with
electric trailer brakes or most electric over
hydraulic trailer brake systems. These
instructions apply to both types of electric
trailer brakes.
This symbol is on the Trailer Brake Control
Panel on vehicles with an ITBC system. The
power output to the trailer brakes is
proportional to the amount of vehicle
braking. This available power output to the
trailer brakes can be adjusted to a wide
range of trailering situations.
The ITBC system is integrated with the
vehicle’s brake, antilock brake, and
StabiliTrak/Electronic Stability Control (ESC)
systems. In trailering conditions that cause
the vehicle’s antilock brake or StabiliTrak/
ESC systems to activate, power sent to the
trailer's brakes will be automatically
adjusted to minimize trailer wheel lock-up.
This does not imply that the trailer has
StabiliTrak/ESC.
If the vehicle’s brake, anti-lock brake,
or StabiliTrak/ESC systems are not
functioning properly, the ITBC system may
not function fully or at all. Make sure all of
these systems are fully operational to allow
the ITBC system to function properly.
The ITBC system is powered through the
vehicle's electrical system. Turning the
ignition off will also turn off the ITBC
system. The ITBC system is fully functional
only when the ignition is in ON/RUN.
{Warning
Connecting a trailer that has an air brake
system may result in reduced or
complete loss of trailer braking, including
increased stopping distance or trailer
instability which could result in serious
(Continued)