Black plate (53,1)GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
5853626) - 2014 - CRC - 6/6/14
Driving and Operating 9-53
Parking Brake
Set the parking brake by holding the
regular brake pedal down, then
pushing down the parking brake
pedal.
If the ignition is on, the brake
system warning light will come on.
SeeBrake System Warning Light on
page 5-24.
{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.
To release the parking brake, hold
the regular brake pedal down, then
push down momentarily on the
parking brake pedal until you feel
the pedal release. Slowly pull your
foot up off the parking brake pedal.
If the parking brake is not released
when you begin to drive, the brake
system warning light will flash and a
chime will sound warning you that
the parking brake is still on.
If you are towing a trailer and are
parking on a hill, see Driving
Characteristics and Towing Tips on
page 9-74.
Brake Assist
This vehicle has a brake assist
feature designed to assist the driver
in stopping or decreasing vehicle
speed in emergency driving
conditions. This feature
automatically uses the stability
system hydraulic brake control
module to supplement the power
brake system under conditions
where the driver has quickly and
forcefully applied the brake pedal in
an attempt to quickly stop or slow
down the vehicle. The stability
system hydraulic brake control
module increases brake pressure at
each corner of the vehicle until the
ABS activates. Minor brake pedal
pulsation or pedal movement during
this time is normal and the driver
should continue to apply the brake
pedal as the driving situation
dictates. The brake assist feature
will automatically disengage when
the brake pedal is released or brake
pedal pressure is quickly
decreased.
Black plate (58,1)GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
5853626) - 2014 - CRC - 6/6/14
9-58 Driving and Operating
If equipped with an Allison or
Hydra-Matic 6-speed automatic
transmission, see“Tow/Haul Mode
Grade Braking” underTow/Haul
Mode on page 9-38 for an
explanation of how cruise control
interacts with the Range Selection
Mode, Tow/Haul Mode, and Grade
Braking systems.
If the cruise control is being used
and the Traction Control (TCS)
system or StabiliTrak begins to limit
wheel spin, the cruise control will
automatically disengage. See
Traction Control/Electronic Stability
Control on page 9-54. If a collision
alert occurs when cruise control is
activated, cruise control is
disengaged. See Forward Collision
Alert (FCA) System on page 9-64.
When road conditions allow the
cruise control to be safely used
again, it can be turned back on.
5(On/Off): Press to turn the
system on or off. The indicator light
is white when cruise control is on
and turns off when cruise control
is off.
+RES (Resume/Accelerate):
Press briefly to make the vehicle
resume to a previously set speed,
or press and hold to accelerate.
If cruise control is already active,
use to increase vehicle speed. SET−
(Set/Coast): Press briefly to
set the speed and activate cruise
control. If cruise control is already
active, use to decrease vehicle
speed.
*(Cancel): Press to disengage
cruise control without erasing the
set speed from memory.
Setting Cruise Control
If the cruise button is on when not in
use, it could get pressed and go into
cruise when not desired. Keep the
cruise control button off when cruise
is not being used.
The cruise control light on the
instrument cluster will come on
green after the cruise control has
been set to the desired speed.
1. Press
5to turn the cruise
system on.
2. Get up to the desired speed.
3. Press and release the SET− button on the steering wheel.
4. Remove foot from the accelerator.
Black plate (60,1)GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
5853626) - 2014 - CRC - 6/6/14
9-60 Driving and Operating
To disable and enable Cruise
Grade Braking for the current
ignition key cycle, press and
hold the Tow/Haul button for
five seconds. A DIC message
displays. SeeTransmission
Messages on page 5-42.
.Vehicles with a diesel engine
have Cruise Grade Braking
enabled when Tow/Haul Mode is
on, the exhaust brake is on,
or both are on.
For other forms of Grade Braking,
see Automatic Transmission on
page 9-33 ,Tow/Haul Mode on
page 9-38, and Hill Descent Control
(HDC) on page 9-56. Ending Cruise Control
There are three ways to end cruise
control:
.To disengage cruise control,
step lightly on the brake pedal.
.To disengage cruise control,
Press
*on the steering wheel.
.To turn off the cruise control,
press
5on the steering wheel.
Erasing Speed Memory
The cruise control set speed is
erased from memory by pressing
5
or if the ignition is turned off.
Driver Assistance
Systems
This vehicle may have features that
work together to help avoid crashes
or reduce crash damage while
driving, backing, and parking. Read
this entire section before using
these systems.
{Warning
Do not rely on the Driver
Assistance Systems. These
systems do not replace the need
for paying attention and driving
safely. You may not hear or feel
alerts or warnings provided by
these systems. Failure to use
proper care when driving may
result in injury, death, or vehicle
damage. See Defensive Driving
on page 9-3.
(Continued)
Black plate (63,1)GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
5853626) - 2014 - CRC - 6/6/14
Driving and Operating 9-63
The vehicle may have an instrument
cluster parking assist display with
bars that show“distance to object”
and object location information for
URPA, and on some vehicles, for
the Front Parking Assist system. As
the object gets closer, more bars
light up.
When an object is first detected in
the rear, one beep will be heard
from the rear, or both sides of the
Safety Alert Seat will pulse two
times. When an object is very close
(<0.6 m (2 ft) in the vehicle rear,
or <0.3 m (1 ft) in the vehicle front),
a continuous beep will sound from the front or rear, or both sides of the
Safety Alert Seat will pulse five
times. Beeps for Front Parking
Assist are higher pitched than for
Rear Parking Assist.
Turning the Features On or Off
TheXbutton on the center stack
is used to turn on or off the Front
and Rear Parking Assist. The
indicator light in the button comes
on when the features are on and
turns off when the features have
been disabled.
Front and Rear Parking Assist can
be turned off, on, or on with towbar
through vehicle personalization. See
“Parking Assist” underVehicle
Personalization on page 5-45. If the
parking assist is turned off through
vehicle personalization, the park assist button on the center stack will
be disabled. To turn the parking
assist on again, select On in the
vehicle personalization menu. The
On with Towbar setting allows for
the parking assist to work properly
with a small item attached to the
trailer hitch. Turn off parking assist
when towing a trailer.
To turn the Rear Vision Camera
(RVC) system rear parking assist
symbols or guidance lines on or off:
1. On the infotainment system
Home screen, press the Settings
screen button, or turn the MENU
knob to highlight Settings and
press MENU.
2. Select Rear Camera.
3. Press Rear Park Assist Symbols or Guidance Lines and then
select Off or On.
Black plate (74,1)GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
5853626) - 2014 - CRC - 6/6/14
9-74 Driving and Operating
Trailer Towing
General Towing
Information
Only use towing equipment that has
been designed for the vehicle.
Contact your dealer or trailering
dealer for assistance with preparing
the vehicle for towing a trailer. Read
the entire section before towing a
trailer.
For towing a disabled vehicle, see
Towing the Vehicle on page 10-93.
For towing the vehicle behind
another vehicle such as a motor
home, seeRecreational Vehicle
Towing on page 10-94.
Driving Characteristics
and Towing Tips
Driving with a Trailer
When towing a trailer:
.Become familiar with the state
and local laws that apply to
trailer towing.
.Do not tow a trailer during the
first 800 km (500 mi) to prevent
damage to the engine, axle,
or other parts.
.Then 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).
Shift the transmission to a lower
gear if the transmission shifts
too often under heavy loads and/
or hilly conditions.
.Turn off Park Assist when
towing.
{Warning
When towing a trailer, exhaust
gases may collect at the rear of
the vehicle and enter if the
liftgate, trunk/hatch, or rear-most
window is open.
(Continued)
Warning (Continued)
When towing a trailer:
.Do not drive with the liftgate,
trunk/hatch, or rear-most
window open.
.Fully open the air outlets on
or under the instrument
panel.
.Also adjust the climate
control system to a setting
that brings in only outside air.
See“Climate Control
Systems” in the Index.
For more information about
Carbon Monoxide, see Engine
Exhaust on page 9-32.
Towing a trailer requires a certain
amount of experience. The
combination you are driving is
longer and not as responsive as the
vehicle itself. Get acquainted with
the handling and braking of the rig
before setting out for the open road.
Black plate (75,1)GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
5853626) - 2014 - CRC - 6/6/14
Driving and Operating 9-75
Before starting, check all trailer hitch
parts and attachments, safety
chains, electrical connectors, lamps,
tires, and mirrors. If the trailer has
electric brakes, start the
combination moving and then apply
the trailer brake controller by hand
to be sure the brakes work.
During the trip, check occasionally
to be sure that the load is secure
and the lamps and any trailer
brakes still work.
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving the vehicle without a trailer.
This can help to avoid heavy
braking and sudden turns.
Passing
More passing distance is needed
when towing a trailer. The
combination will not accelerate as
quickly and is longer so it is
necessary to go much farther
beyond the passed vehicle before
returning to the lane.
Backing Up
Hold the bottom of the steering
wheel with one hand. To move the
trailer to the left, move that hand to
the left. To move the trailer to the
right, move your hand to the right.
Always back up slowly and,
if possible, have someone
guide you.
Making Turns
{Caution
Making very sharp turns while
trailering could cause the trailer to
come in contact with the vehicle.
The vehicle could be damaged.
Avoid making very sharp turns
while trailering.
When turning with a trailer, make
wider turns than normal. Do this so
the trailer will not strike soft
shoulders, curbs, road signs, trees,
or other objects. Avoid jerky or
sudden maneuvers. Signal well in
advance. If the trailer turn signal bulbs burn
out, the arrows on the instrument
cluster will still flash for turns. It is
important to check occasionally to
be sure the trailer bulbs are still
working.
Driving on Grades
Reduce speed and shift to a lower
gear
before starting down a long or
steep downgrade. If the
transmission is not shifted down, the
brakes might get hot and no longer
work well.
Vehicles can tow in D (Drive). Shift
the transmission to a lower gear if
the transmission shifts too often
under heavy loads and/or hilly
conditions.
The Tow/Haul Mode may be used if
the transmission shifts too often.
See Tow/Haul Mode on page 9-38.
When towing at high altitude on
steep uphill grades, consider the
following: Engine coolant will boil at
a lower temperature than at normal
altitudes. If the engine is turned off
Black plate (76,1)GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
5853626) - 2014 - CRC - 6/6/14
9-76 Driving and Operating
immediately after towing at high
altitude on steep uphill grades, the
vehicle may show signs similar to
engine overheating. To avoid this,
let the engine run while parked,
preferably on level ground, with the
transmission in P (Park) for a few
minutes before turning the engine
off. If the overheat warning comes
on, seeEngine Overheating on
page 10-23.
Parking on Hills
{Warning
Parking the vehicle on a hill with
the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface. If parking the rig on a hill:
1. Press the brake pedal, but do
not shift into P (Park) yet. Turn
the wheels into the curb if facing
downhill or into traffic if facing
uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the regular brakes
until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking brake and shift
into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
2. Start the engine.
3. Shift into a gear.
4. Release the parking brake. 5. Let up on the brake pedal.
6. Drive slowly until the trailer is
clear of the chocks.
7. Stop and have someone pick up and store the chocks.
Maintenance when Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See
Maintenance Schedule on
page 11-3. Things that are
especially important in trailer
operation are automatic
transmission fluid, engine oil, axle
lubricant, belts, cooling system, and
brake system. It is a good idea to
inspect these before and during
the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Black plate (77,1)GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
5853626) - 2014 - CRC - 6/6/14
Driving and Operating 9-77
Trailer Towing
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
If the vehicle is bi-fuel, see the
bi-fuel supplement.
Do not tow a trailer during break-in.
SeeNew Vehicle Break-In on
page 9-23.
{Warning
The driver can lose control when
pulling a trailer if the correct
equipment is not used or the
vehicle is not driven properly.
For example, if the trailer is too
heavy, the brakes may not work
well or even at all. The driver and
passengers could be seriously
injured. The vehicle may also be
damaged; the resulting repairs
would not be covered by the
vehicle warranty.
(Continued)
Warning (Continued)
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.
{Caution
Pulling a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To pull a trailer
correctly, follow the advice in this
section and see your dealer for
important information about
towing a trailer with the vehicle.
To identify the trailering capacity of
the vehicle, read the information in
“Weight of the Trailer” later in this
section. 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.