transmission GMC SIERRA 2015 User Guide

Black plate (31,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Instruments and Controls 5-31
Transmission Fluid Temperature
Gauge:Shows the temperature of
the automatic transmission fluid in
either degrees Celsius (°C) or
degrees Fahrenheit (°F).
Off Road: Displays vehicle pitch
and roll information, road wheel
angle, and four-wheel drive (4WD)
status.Vehicle Messages
Messages displayed on the DIC
indicate the status of the vehicle or
some action may be needed to
correct a condition. Multiple
messages may appear one after
another.
The messages that do not require
immediate action can be
acknowledged and cleared by
pressing
V.
The messages that require
immediate action cannot be cleared
until that action is performed.
All messages should be taken
seriously and clearing the message
does not correct the problem.
The following are the possible
messages and some information
about them.
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
Battery Voltage and
Charging Messages
BATTERY LOW START
VEHICLE
When the vehicle’ s battery is
severely discharged, this message
will display and four chimes will
sound. Start the vehicle
immediately. If the vehicle is not
started and the battery continues to
discharge, the climate controls,
heated seats, and audio systems
will shut off and the vehicle may
require a jump start. These systems
will function again after the vehicle
is started.
BATTERY SAVER ACTIVE
This message displays when the
battery voltage drops below
expected levels and features are
disabled. Turn off all unnecessary
accessory features.

Black plate (33,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Instruments and Controls 5-33
Door Ajar Messages
DOOR OPEN
This message displays and a chime
may sound if a door is not fully
closed. Stop and turn off the
vehicle, check the door for
obstructions, and close the door
again. Check to see if the message
still appears on the DIC.
HOOD OPEN
This message displays and a chime
may sound if the hood is not fully
closed. Stop and turn off the
vehicle, check the hood for
obstructions, and close the hood
again. Check to see if the message
still appears on the DIC.
Engine Cooling System
Messages
A/C OFF DUE TO HIGH
ENGINE TEMP
This message displays when the
engine coolant becomes hotter than
the normal operating temperature.
SeeEngine Coolant Temperature
Gauge on page 5-13. To avoid
added strain on a hot engine, the air
conditioning compressor
automatically turns off. When the
coolant temperature returns to
normal, the air conditioning
compressor turns back on. You can
continue to drive your vehicle.
If this message continues to appear,
have the system repaired by your
dealer as soon as possible to avoid
damage to the engine.
ENGINE OVERHEATING IDLE
ENGINE
This message displays when the
engine coolant temperature is too
hot. Stop and allow the vehicle to
idle until it cools down. See Engine
Coolant Temperature Gauge on
page 5-13.
When towing, use Tow/Haul mode
to prevent damage to the engine or
transmission. See Tow/Haul Mode
on page 9-39.
ENGINE OVERHEATED STOP
ENGINE
This message displays and a chime
may sound if the engine cooling
system reaches unsafe
temperatures for operation. Stop
and turn off the vehicle as soon as it
is safe to do so to avoid severe
damage. This message clears when
the engine has cooled to a safe
operating temperature.

Black plate (39,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Instruments and Controls 5-39
If the warning comes on and stays
on, there may be a problem with the
TPMS. See your dealer.
TIRE LEARNING ACTIVE
If equipped with the Tire Pressure
Monitor System (TPMS), this
message displays when the system
is relearning the tire positions on
your vehicle. The tire positions must
be relearned after rotating the tires
or after replacing a tire or sensor.
SeeTire Inspection on page 10-65,
Tire Rotation on page 10-65, Tire
Pressure Monitor System on
page 10-61, and Tire Pressure on
page 10-59.
TIRE PRESSURE LOW ADD
AIR TO TIRE
If equipped with the Tire Pressure
Monitor System (TPMS), this
message displays when the
pressure in one or more of the
vehicle's tires is low. This message
also displays with a vehicle picture
to indicate the location of the low
tire. The low tire pressure warning
light will also come on. See Tire
Pressure Light on page 5-25. You
can receive more than one tire
pressure message at a time. If a tire
pressure message appears on the
DIC, stop as soon as you can. Have
the tire pressures checked and set
to those shown on the Tire and
Loading Information label. See Tires
on page 10-50, Vehicle Load Limits
on page 9-15, and Tire Pressure on
page 10-59. The DIC also shows
the tire pressure values. See Driver
Information Center (DIC) on
page 5-27.
Transmission Messages
4WD OFF
If equipped with four-wheel drive,
this message displays when the
four-wheel-drive system is
temporarily disabled due to an
overheated condition. The vehicle
will run in two-wheel drive when this
message is present. Once the
four-wheel-drive system cools down,
the message turns off and the
four-wheel-drive system returns to
normal operation.
4WD SHIFT IN PROGRESS
This message will display while the
four-wheel-drive system is shifting.
FOR 4WD LOW SHIFT TO
NEUTRAL
If a four-wheel drive shift into 4nis
requested, and the vehicle speed is
correct, but the transmission is not
in N (Neutral), this message will
display until the transmission is
shifted to N (Neutral).

Black plate (40,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
5-40 Instruments and Controls
FOR 4WD LOW SLOW TO XXX
If a four-wheel drive shift into 4nis
requested, but the vehicle speed is
too high, this message will display
until the correct vehicle speed is
reached.
GRADE BRAKING ACTIVE
This message displays when grade
braking has been activated while
driving on downhill grades. This
message will only appear the first
time the feature is activated in an
ignition cycle. See Tow/Haul Mode
on page 9-39, Automatic
Transmission on page 9-33, and
Cruise Control on page 9-52.
GRADE BRAKING OFF
This message displays when grade
braking has been disabled with the
Tow/Haul Mode button on the end of
the shift lever. See Tow/Haul Mode
on page 9-39, Automatic
Transmission on page 9-33, and
Cruise Control on page 9-52.
GRADE BRAKING ON
This message displays when grade
braking has been enabled with the
Tow/Haul Mode button on the end of
the shift lever. See Tow/Haul Mode
on page 9-39, Automatic
Transmission on page 9-33, and
Cruise Control on page 9-52.
SERVICE 4WD
If the vehicle has four-wheel drive,
this message may display if a
problem occurs with the
four-wheel-drive system. If this
message appears, stop as soon as
possible and turn off the vehicle.
Make sure the key is in the LOCK/
OFF position for at least
one minute, then restart the vehicle
and check for the message on the
DIC display. If the message is still
displayed or appears again when
you begin driving, the
four-wheel-drive system needs
service. See your dealer.
SHIFT DENIED
This message displays when the
shift lever is in M (Manual Mode)
and a transmission range has been
selected that is unavailable at the
current vehicle speed.
TO EXIT 4WD LOW SHIFT TO
NEUTRAL
If a four-wheel drive shift out of 4nis
requested, and the vehicle speed is
correct, but the transmission is not
in N (Neutral), this message will
display until the transmission is
shifted to N (Neutral).
TO EXIT 4WD LOW SLOW
TO XXX
If a four-wheel drive shift out of 4nis
requested, but the vehicle speed is
too high, this message will display
until the correct vehicle speed is
reached.

Black plate (41,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Instruments and Controls 5-41
TRANSMISSION HOT IDLE
ENGINE
This message displays and a chime
may sound if the transmission fluid
in the vehicle gets hot. Driving with
the transmission fluid temperature
high can cause damage to the
vehicle. Stop the vehicle and let it
idle to allow the transmission to
cool. This message clears and the
chime stops when the fluid
temperature reaches a safe level.
When towing, use Tow/Haul Mode
to prevent damage to the engine or
transmission. SeeTow/Haul Mode
on page 9-39.
VEHICLE IN 4WD LOW
This message will display if the
vehicle is driven in 4
nfor about
10 minutes above 72 km/h (45 mph).
Vehicle Reminder
Messages
CHECK TRAILER WIRING
On vehicles with the Integrated
Trailer Brake Control (ITBC) system,
this message may display and a
chime may sound when one of the
following conditions exists:
.A trailer with electric brakes
becomes disconnected from the
vehicle.
‐ If the disconnect occurs while
the vehicle is stopped, this
message clears itself after a
short time.
‐ If the disconnect occurs while
the vehicle is moving, this
message stays on until the
ignition is turned off.
.There is a short in the wiring to
the electric trailer brakes.
When this message displays, power
is no longer available to the trailer
brakes. As soon as it is safe to do so,
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. This message clears if the trailer
is reconnected. This message also
clears if you acknowledge it. If this
message still displays, either the
vehicle or the trailer needs service.
See your dealer.
See
“Integrated Trailer Brake
Control System” underTowing
Equipment on page 9-78.
ICE POSSIBLE DRIVE
WITH CARE
This message displays when ice
conditions are possible.
TRAILER CONNECTED
On vehicles with the Integrated
Trailer Brake Control (ITBC) system,
this message displays briefly when
a trailer with electric or electric over
hydraulic brakes is first connected
to the vehicle.

Black plate (50,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
5-50 Instruments and Controls
Do not use the Universal Remote
system with any garage door opener
that does not have the stop and
reverse feature. This includes any
garage door opener model
manufactured before April 1, 1982.
Read the instructions completely
before programming the Universal
Remote system. It may help to have
another person assist with the
programming process.
Keep the original hand-held
transmitter for use in other vehicles
as well as for future programming.
Erase the programming when
vehicle ownership is terminated.
See“Erasing Universal Remote
System Buttons” later in this
section.
To program a garage door opener,
park outside directly in line with and
facing the garage door opener
receiver. Clear all people and
objects near the garage door. Make sure the hand-held transmitter
has a new battery for quick and
accurate transmission of the
radio-frequency signal.
Programming the Universal
Remote System
For questions or help programming
the Universal Remote system, call
1-800-355-3515 or see
www.homelink.com.
Programming involves
time-sensitive actions, and may time
out causing the procedure to be
repeated.
To program up to three devices:
1. Hold the end of the hand-held
transmitter about 3 to 8 cm (1 to
3 in) away from the Universal
Remote system buttons with the
indicator light in view. The
hand-held transmitter was
supplied by the manufacturer of
the garage door opener receiver. 2. At the same time, press and
hold both the hand-held
transmitter button and one of the
three Universal Remote system
buttons to be used to operate
the garage door. Do not release
either button until the indicator
light goes from a slow to a rapid
flashing light. Then release both
buttons.
Some garage door openers may
require substitution of Step 2
with the procedure under “Radio
Signals for Canada and Some
Gate Operators” later in this
section.
3. Press and hold the newly programmed Universal Remote
system button for five seconds
while watching the indicator light
and garage door activation.
.If the indicator light stays on
continuously or the garage
door moves when the
button is pressed, then

Black plate (51,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Instruments and Controls 5-51
programming is complete.
There is no need to
complete Steps 4–6.
.If the indicator light does
not come on or the garage
door does not move, a
second button press may
be required. For a second
time, press and hold the
newly programmed button
for five seconds. If the light
stays on or the garage door
moves, programming is
complete.
.If the indicator light blinks
rapidly for two seconds,
then changes to a solid light
and the garage door does
not move, continue with
programming Steps 4–6.
Learn or Smart Button
4. After completing Steps 1–3, locate the Learn or Smart button
inside the garage on the garage
door opener receiver. The name
and color of the button may vary
by manufacturer.
5. Press and release the Learn or Smart button. Step 6 must be
completed within 30 seconds of
pressing this button.
6. Inside the vehicle, press and hold the newly programmed
Universal Remote system button
for two seconds and then
release it. If the garage door
does not move or the lamp on
the garage door opener receiver does not flash, press and hold
the same button a second time
for two seconds, then release it.
Again, if the door does not move
or the garage door lamp does
not flash, press and hold the
same button a third time for
two seconds, then release it.
The Universal Remote system
should now activate the
garage door.
Repeat the process for
programming the two remaining
buttons.
Radio Signals for Canada and
Some Gate Operators
For questions or programming help,
call 1-800-355-3515 or see
www.homelink.com.
Canadian radio-frequency laws and
some U.S. gate operators require
transmitter signals to time out or quit
after several seconds of
transmission. This may not be long

Black plate (3,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Lighting 6-3
to pass. It works even if the
headlamps are in the automatic
position.
To use it, pull the turn signal lever
toward you, then release it.
If the headlamps are in the
automatic position or on low beam,
the high-beam headlamps will turn
on. They will stay on as long as you
hold the lever toward you. The
high-beam indicator on the
instrument cluster will come on.
Release the lever to return to
normal operation.
Daytime Running
Lamps (DRL)
DRL can make it easier for others to
see the front of the vehicle during
the day. Fully functional DRL are
required on all vehicles first sold in
Canada.
The DRL system comes on when
the following conditions are met:
.The ignition is on.
.The exterior lamp control is
in AUTO.
.The transmission is not in
P (Park).
.The light sensor determines it is
daytime.
When the DRL system is on, only
the DRL are on. The taillamps,
sidemarker lamps, instrument panel
lights, and other lamps will not
be on.
When it begins to get dark, the
automatic headlamp system
switches from DRL to the
headlamps.
To turn off the DRL, turn the exterior
lamp control to the off position and
then release. For vehicles first sold
in Canada, off will only work when
the vehicle is in P (Park).
Automatic Headlamp
System
When the exterior lamp control is
set to AUTO and it is dark enough
outside, the headlamps come on
automatically.
There is a light sensor on top of the
instrument panel. Do not cover the
sensor, otherwise the headlamps
will come on when they are not
needed.
The system may also turn on the
headlamps when driving through a
parking garage or tunnel.

Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-1
Driving and
Operating
Driving Information
Distracted Driving . . . . . . . . . . . . . 9-2
Defensive Driving . . . . . . . . . . . . . 9-3
Drunk Driving . . . . . . . . . . . . . . . . . 9-3
Control of a Vehicle . . . . . . . . . . . 9-3
Braking . . . . . . . . . . . . . . . . . . . . . . . 9-3
Steering . . . . . . . . . . . . . . . . . . . . . . . 9-4
Off-Road Recovery . . . . . . . . . . . . 9-5
Loss of Control . . . . . . . . . . . . . . . . 9-5
Off-Road Driving . . . . . . . . . . . . . . 9-6
Driving on Wet Roads . . . . . . . . 9-11
Hill and Mountain Roads . . . . . 9-11
Winter Driving . . . . . . . . . . . . . . . 9-12
If the Vehicle Is Stuck . . . . . . . . 9-14
Vehicle Load Limits . . . . . . . . . . 9-15
Truck-Camper LoadingInformation . . . . . . . . . . . . . . . . . 9-21
Starting and Operating
New Vehicle Break-In . . . . . . . . 9-23
Adjustable Throttle and BrakePedal . . . . . . . . . . . . . . . . . . . . . . . 9-23
Ignition Positions . . . . . . . . . . . . 9-24
Starting the Engine . . . . . . . . . . 9-26 Fast Idle System . . . . . . . . . . . . . 9-27
Engine Heater . . . . . . . . . . . . . . . 9-28
Retained Accessory
Power (RAP) . . . . . . . . . . . . . . . 9-29
Shifting Into Park . . . . . . . . . . . . 9-30
Shifting out of Park . . . . . . . . . . 9-31
Parking over Things
That Burn . . . . . . . . . . . . . . . . . . 9-32
Active Fuel Management
®. . . 9-32
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . 9-32
Running the Vehicle While Parked . . . . . . . . . . . . . . . . . . . . . 9-33
Automatic Transmission
Automatic Transmission . . . . . 9-33
Manual Mode . . . . . . . . . . . . . . . . 9-36
Tow/Haul Mode . . . . . . . . . . . . . . 9-39
Drive Systems
Four-Wheel Drive . . . . . . . . . . . . 9-40
Brakes
Antilock BrakeSystem (ABS) . . . . . . . . . . . . . . 9-46
Parking Brake . . . . . . . . . . . . . . . 9-47
Brake Assist . . . . . . . . . . . . . . . . . 9-48
Hill Start Assist (HSA) . . . . . . . 9-48
Ride Control Systems
Traction Control/Electronic Stability Control . . . . . . . . . . . . 9-49
Hill Descent Control (HDC) . . . . . . . . . . . . . . 9-51
Locking Rear Axle . . . . . . . . . . . 9-52
Cruise Control
Cruise Control . . . . . . . . . . . . . . . 9-52
Driver Assistance Systems
Driver Assistance
Systems . . . . . . . . . . . . . . . . . . . . 9-55
Assistance Systems for Parking or Backing . . . . . . . . . 9-56
Assistance Systems for Driving . . . . . . . . . . . . . . . . . . . . . 9-59
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . 9-59
Lane Departure Warning (LDW) . . . . . . . . . . . . . 9-61
Fuel
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . 9-63
California FuelRequirements . . . . . . . . . . . . . . 9-64
Fuels in Foreign Countries . . . 9-64
Fuel Additives . . . . . . . . . . . . . . . 9-64

Black plate (8,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-8 Driving and Operating
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 an accident.
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 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 case overrides the
transmission. You or someone
else could be injured. If leaving
the vehicle, set the parking brake
and shift the transmission to
P (Park). Shift the transfer case to
any position but N (Neutral).
.When driving down a hill, keep
the vehicle headed straight
down. Use a low gear because
the engine will work with thebrakes to slow the vehicle and
help keep the vehicle under
control.
{Warning
Heavy braking when going down
a hill can cause your brakes to
overheat and fade. This could
cause loss of control and you or
others could be injured or killed.
Apply the brakes lightly when
descending a hill and use a low
gear to keep vehicle speed under
control.
If the vehicle stalls on a hill:
1. Apply the brakes to stop the vehicle, and then apply the
parking brake.