
GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
256 Driving and Operating
Driving and
Operating
Driving Information
Distracted Driving . . . . . . . . . . . . 257
Defensive Driving . . . . . . . . . . . . . 258
Drunk Driving . . . . . . . . . . . . . . . . . 258
Control of a Vehicle . . . . . . . . . . . 258
Braking . . . . . . . . . . . . . . . . . . . . . . . 258
Steering . . . . . . . . . . . . . . . . . . . . . . 259
Off-Road Recovery . . . . . . . . . . . 260
Loss of Control . . . . . . . . . . . . . . . 260
Off-Road Driving . . . . . . . . . . . . . 261
Driving on Wet Roads . . . . . . . . 265
Hill and Mountain Roads . . . . . 266
Winter Driving . . . . . . . . . . . . . . . . 267
If the Vehicle Is Stuck . . . . . . . . 268
Vehicle Load Limits . . . . . . . . . . . 269
Truck-Camper LoadingInformation . . . . . . . . . . . . . . . . . . 275
Starting and Operating
New Vehicle Break-In . . . . . . . . . 277
Adjustable Throttle and BrakePedal . . . . . . . . . . . . . . . . . . . . . . . 277
Ignition Positions . . . . . . . . . . . . . 278
Starting the Engine . . . . . . . . . . . 279
Fast Idle System . . . . . . . . . . . . . 280 Retained Accessory
Power (RAP) . . . . . . . . . . . . . . . . 281
Engine Coolant Heater . . . . . . . 281
Shifting Into Park . . . . . . . . . . . . . 283
Shifting out of Park . . . . . . . . . . . 284
Parking over Things That Burn . . . . . . . . . . . . . . . . . . . 285
Active Fuel Management
®. . . . 285
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . 285
Running the Vehicle While Parked . . . . . . . . . . . . . . . . . . . . . . 286
Automatic Transmission
Automatic Transmission . . . . . . 286
Manual Mode . . . . . . . . . . . . . . . . . 289
Tow/Haul Mode . . . . . . . . . . . . . . . 292
Drive Systems
Four-Wheel Drive . . . . . . . . . . . . . 293
Brakes
Antilock BrakeSystem (ABS) . . . . . . . . . . . . . . . 300
Parking Brake . . . . . . . . . . . . . . . . 301
Brake Assist . . . . . . . . . . . . . . . . . . 302
Hill Start Assist (HSA) . . . . . . . . 302
Ride Control Systems
Traction Control/Electronic Stability Control . . . . . . . . . . . . . 303 Hill Descent Control (HDC) . . . 305
Locking Rear Axle . . . . . . . . . . . . 305
Cruise Control
Cruise Control . . . . . . . . . . . . . . . . 306
Driver Assistance Systems
Driver Assistance Systems . . . 309
Assistance Systems for
Parking or Backing . . . . . . . . . . 309
Assistance Systems for Driving . . . . . . . . . . . . . . . . . . . . . . 312
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . . 312
Lane Departure Warning (LDW) (2500/3500
Series) . . . . . . . . . . . . . . . . . . . . . . 314
Lane Keep Assist (LKA) (1500 Series) . . . . . . . . . . . . . . . . . . . . . . 315
Fuel
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 317
California FuelRequirements . . . . . . . . . . . . . . . 318
Fuels in Foreign Countries . . . 319
Fuel Additives . . . . . . . . . . . . . . . . 319
E85 or FlexFuel . . . . . . . . . . . . . . 319
Filling the Tank . . . . . . . . . . . . . . . 320
Filling a Portable Fuel Container . . . . . . . . . . . . . . . . . . . 322

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
Driving and Operating 263
{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
(Continued)
Warning (Continued)
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 the
brakes 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
(Continued)
Warning (Continued)
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.
2. Shift into P (Park) and then restart the engine.
.If driving uphill when the
vehicle stalls, shift to
R (Reverse), release the
parking brake, and back
straight down.
. Never try to turn the vehicle
around. If the hill is steep
enough to stall the vehicle,
it is steep enough to cause
it to roll over.
. If you cannot make it up the
hill, back straight down
the hill.

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
278 Driving and Operating
Ignition Positions
Vehicles with Key Access have an
ignition switch with four different
positions.
To shift out of P (Park), the ignition
must be in ON/RUN or ACC/
ACCESSORY and the regular brake
pedal must be applied.
0 (STOPPING THE ENGINE/LOCK/
OFF) :When the vehicle is stopped,
turn the ignition switch to LOCK/
OFF to turn the engine off. Retained
Accessory Power (RAP) will remain
active. See Retained Accessory
Power (RAP) 0281. This position locks the ignition and
steering wheel. It also locks the
transmission on automatic
transmission vehicles. The key can
be removed in LOCK/OFF.
The steering can bind with the
wheels turned off center. If this
happens, move the steering wheel
from right to left while turning the
key to ACC/ACCESSORY. If this
does not work, then the vehicle
needs service.
Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake
and steering systems and disable
the airbags.
If the vehicle must be shut off in an
emergency:
1. Brake using a firm and steady pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.
2. Shift the vehicle to N (Neutral). This can be done while the
vehicle is moving. After shifting to N (Neutral), firmly apply the
brakes and steer the vehicle to
a safe location.
3. Come to a complete stop, shift to P (Park), and turn the
ignition to LOCK/OFF. On
vehicles with an automatic
transmission, the shift lever
must be in P (Park) to turn the
ignition switch to the LOCK/
OFF position.
4. Set the parking brake. See Parking Brake 0301.{Warning
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, only shut the
vehicle off in an emergency.
If the vehicle cannot be pulled over,
and must be shut off while driving,
turn the ignition to ACC/
ACCESSORY.

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
Driving and Operating 279
Caution
Using a tool to force the key to
turn in the ignition could cause
damage to the switch or break the
key. Use the correct key, make
sure it is all the way in, and turn it
only with your hand. If the key
cannot be turned by hand, see
your dealer.
1 (ACC/ACCESSORY) : This
position lets things like the radio
and the windshield wipers operate
while the engine is off. It also
unlocks the steering wheel. Use this
position if the vehicle must be
pushed or towed.
2 (ON/RUN) : This position can be
used to operate the electrical
accessories and to display some
instrument cluster warning and
indicator lights. This position can
also be used for service and
diagnostics, and to verify the proper
operation of the malfunction
indicator lamp as may be required
for emission inspection purposes.
The switch stays in this position when the engine is running. The
transmission is also unlocked in this
position on automatic transmission
vehicles.
If the key is left in the ACC/
ACCESSORY or ON/RUN position
with the engine off, the battery could
be drained. The vehicle may not
start if the battery is allowed to drain
for an extended period of time.
3 (START) :
This is the position that
starts the engine. When the engine
starts, release the key. The ignition
switch returns to ON/RUN for
driving.
A warning tone will sound when the
driver door is opened and the
ignition is in ACC/ACCESSORY or
LOCK/OFF, and the key is in the
ignition.
Starting the Engine
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
For an eAssist vehicle, see the
Silverado/Sierra eAssist
supplement.
Caution
If you add electrical parts or
accessories, you could change
the way the engine operates. Any
resulting damage would not be
covered by the vehicle warranty.
See Add-On Electrical
Equipment 0349.
Caution
If the steering wheel is turned
until it reaches the end of its
travel, and is held in that position
while starting the vehicle, damage
may occur to the hydraulic power
steering system and there may be
loss of power steering assist.
Move the shift lever to P (Park) or
N (Neutral). To restart the engine
when the vehicle is already moving,
use N (Neutral) only.

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
286 Driving and Operating
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 0283 and
Engine Exhaust 0285.
If parking on a hill and pulling a
trailer, see Driving Characteristics
and Towing Tips 0322.
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
turned to the ON/RUN position.
There are several different positions
for the shift lever.
Heavy-Duty 6-Speed Automatic
Transmission Shown, Others
Similar
See “Range Selection Mode” under
Manual Mode 0289.
P : This position locks the rear
wheels. It is the best position to use
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

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
Driving and Operating 289
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 you are
stuck, do not spin the tires. When
stopping on a hill, use the brakes
to hold the vehicle in place.
Normal Mode Grade Braking
If equipped with a gasoline engine
and an automatic transmission,
Normal Mode Grade Braking is
enabled when the vehicle is started,
but is not enabled in Range
Selection Mode. It assists in
maintaining desired vehicle speeds
when driving on downhill grades by
using the engine and transmission
to slow the vehicle. The first time
the system engages for each
ignition key cycle, a DIC message
will be displayed. SeeTransmission
Messages 0160. To disable or enable Normal Mode
Grade Braking within the current
ignition key cycle, press and hold
the Tow/Haul button for
five seconds. When the button is
released, the requested mode
change is made. A DIC message
displays. See
Transmission
Messages 0160.
For other forms of grade braking,
see Tow/Haul Mode 0292 and
Cruise Control 0306.
Kickdown Mode
The accelerator pedal provides an
additional downshift after pressing
through the kickdown feature.
It requires extra pedal pressure near
the end of its travel to engage.
Manual Mode
Range Selection Mode
If equipped, 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 M (Manual Mode).
2. Press the plus/minus buttons on the shift lever to select the
desired range of gears for
current driving conditions.
With an 8–speed automatic
transmission, hold the plus/minus
buttons on the shift lever to select

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
290 Driving and Operating
the highest or lowest range
available for the current vehicle
speed.
When the shift lever is moved from
D (Drive) to M (Manual Mode), a
number displays next to the M,
indicating the current transmission
range.
This number is the highest gear that
the transmission will command while
operating in M (Manual Mode). All
gears below that number are
available. As driving conditions
change, the transmission can
automatically shift to lower gears.
For example, when M5 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.In vehicles with gasoline engines,
when the shift lever is moved from
D (Drive) to M (Manual Mode), a
downshift may occur. The gear that
the transmission is operating in
when the shift lever is moved from
D (Drive) to M (Manual Mode)
determines if a downshift occurs.
See the following chart.

GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
Driving and Operating 291
6-Speed Automatic TransmissionGear before shifting from D
(Drive) to M (Manual Mode) 6th 5th 4th 3rd 2nd 1st
Range after shifting from D
(Drive) to M (Manual Mode) M4 M4 M3 M2 M2 M1
8-Speed Automatic Transmission Gear before
shifting from D
(Drive) to M
(Manual Mode) 8th 7th 6th 5th 4th 3rd 2nd 1st
Range after
shifting from
D (Drive) to
M (Manual Mode)
– Tow/Haul not
engaged M6 M6 M5 M4 M3 M3 M2 M1
Range after
shifting from
D (Drive) to
M (Manual Mode)
– Tow/Haul
engaged M6 M5 M4 M3 M3 M3 M2 M1 Grade Braking is not available when
Range Selection Mode is active.
See
Tow/Haul Mode 0292.
While using Range Selection Mode,
cruise control and the Tow/Haul
Mode can be used.
If the vehicle has an exhaust brake,
it can also be used, but will not
automatically downshift the
transmission. See “Exhaust Brake”
in the Duramax diesel supplement.
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 you are
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