2012 GMC SIERRA 1500 four wheel drive

Black plate (1,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
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 . . . . . . . . . . . 9-4
Braking . . . . . . . . . . . . . . . . . . . . . . . 9-4
Steering . . . . . . . . . . . . . . . . . . . . . . . 9-4
Off-Road Recovery . . . . . . . . . . . . 9-5
Loss of Control . . . . . . . . . . . . . . . . 9-5
Off-Road Driving . . . . . . . . . . . . . . 9-6
Driving on Wet Roads . . . . . . . . 9-11
Highway Hypnosis . . . . . . . . . . . 9-12
Hill and Mountain Roads . . . . . 9-12
Winter Driving . . . . . . . . . . . . . . . 9-13
If the Vehicle Is Stuck . . . . . . . . 9-15
Vehicle Load Limits . . . . . . . . . . 9-16
Truck-Camper LoadingInformation . . . . . . . . . . . . . . . . . 9-23
Starting and Operating
New Vehicle Break-In . . . . . . . . 9-25
Adjustable Throttle and BrakePedal . . . . . . . . . . . . . . . . . . . . . . . 9-25
Ignition Positions . . . . . . . . . . . . 9-26 Starting the Engine . . . . . . . . . . 9-27
Fast Idle System . . . . . . . . . . . . . 9-29
Retained Accessory
Power (RAP) . . . . . . . . . . . . . . . 9-29
Engine Coolant Heater . . . . . . . 9-30
Shifting Into Park . . . . . . . . . . . . 9-30
Shifting out of Park . . . . . . . . . . 9-32
Parking over Things
That Burn . . . . . . . . . . . . . . . . . . 9-32
Active Fuel Management
®. . . 9-32
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . 9-33
Running the Vehicle While Parked . . . . . . . . . . . . . . . . . . . . . 9-34
Automatic Transmission
Automatic Transmission . . . . . 9-35
Manual Mode . . . . . . . . . . . . . . . . 9-38
Tow/Haul Mode . . . . . . . . . . . . . . 9-39
Drive Systems
Four-Wheel Drive . . . . . . . . . . . . 9-40
Brakes
Antilock BrakeSystem (ABS) . . . . . . . . . . . . . . 9-53
Parking Brake . . . . . . . . . . . . . . . 9-54
Brake Assist . . . . . . . . . . . . . . . . . 9-54
Hill Start Assist (HSA) . . . . . . . 9-54
Ride Control Systems
StabiliTrak®System . . . . . . . . . 9-55
Locking Rear Axle . . . . . . . . . . . 9-58
Cruise Control
Cruise Control . . . . . . . . . . . . . . . 9-58
Object Detection Systems
Ultrasonic Parking Assist . . . . 9-61
Rear Vision Camera (RVC) . . . . . . . . . . . . . 9-62
Fuel
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . 9-68
Recommended Fuel . . . . . . . . . 9-68
Gasoline Specifications (U.S.and Canada Only) . . . . . . . . . . 9-69
California Fuel Requirements . . . . . . . . . . . . . . 9-69
Fuels in Foreign Countries . . . 9-69
Fuel Additives . . . . . . . . . . . . . . . 9-70
Fuel E85 (85% Ethanol) . . . . . 9-71
Filling the Tank . . . . . . . . . . . . . . 9-72
Filling a Portable Fuel Container . . . . . . . . . . . . . . . . . . . 9-73

Black plate (6,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
9-6 Driving and Operating
.Try to avoid sudden steering,
acceleration, or braking,
including reducing vehicle speed
by shifting to a lower gear. Any
sudden changes could cause
the tires to slide.
Remember: Antilock brakes help
avoid only the braking skid.
Off-Road Driving
Four-wheel-drive vehicles can be
used for off-road driving. Vehicles
without four-wheel drive and
vehicles not equipped with All
Terrain (AT) or On-Off Road (OOR)
tires must not be driven off-road
except on a level, solid surface. To
contact the tire manufacturer for
more information about the original
equipment tires, see the Limited
Warranty and Owner Assistance
Information manual.
Controlling the vehicle is the key to
successful off-road driving. One of
the best ways to control the vehicle
is to control the speed.
{WARNING
When driving off-road, bouncing
and quick changes in direction
can easily throw you out of
position. This could cause you to
lose control and crash. You and
your passengers should always
wear safety belts.
Before Driving Off-Road
.Have all necessary maintenance
and service work completed.
.Fuel the vehicle, fill fluid levels,
and check inflation pressure in
all tires, including the spare,
if equipped.
.Read all the information about
four-wheel-drive vehicles in this
manual.
.Make sure all underbody
shields, if equipped, are properly
attached.
.Know the local laws that apply to
off-road driving. To gain more ground clearance if
needed, it may be necessary to
remove the front fascia lower
air dam.
Notice:
Operating the vehicle
for extended periods without
the front fascia lower air dam
installed can cause improper air
flow to the engine. Re‐attach the
front fascia air dam after off-road
driving.
Loading the Vehicle for
Off-Road Driving
{WARNING
.Unsecured cargo on the
load floor can be tossed
about when driving over
rough terrain. You or your
passengers can be struck by
flying objects. Secure the
cargo properly.
(Continued)

Black plate (15,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Driving and Operating 9-15
If it takes some time for help to
arrive, now and then when you run
the engine, push the accelerator
pedal slightly so the engine runs
faster than the idle speed. This
keeps the battery charged to restart
the vehicle and to signal for help
with the headlamps. Do this as little
as possible to save fuel.
If the Vehicle Is Stuck
Slowly and cautiously spin the
wheels to free the vehicle when
stuck in sand, mud, ice, or snow.
See“Rocking Your Vehicle to Get It
Out” later in this section.
If the vehicle has a traction system,
it can often help to free a stuck
vehicle. Refer to the vehicle's
traction system in the Index. If stuck
too severely for the traction system
to free the vehicle, turn the traction
system off and use the rocking
method.
{WARNING
If the vehicle's tires spin at high
speed, they can explode, and you
or others could be injured. The
vehicle can overheat, causing an
engine compartment fire or other
damage. Spin the wheels as little
as possible and avoid going
above 56 km/h (35 mph).
For information about using tire
chains on the vehicle, see Tire
Chains on page 10‑74.
Rocking Your Vehicle to Get
It Out
Turn the steering wheel left and
right to clear the area around the
front wheels. For four-wheel-drive
vehicles, shift into Four‐Wheel High. For vehicles with StabiliTrak
®, turn
the traction control part of the
system off. Shift back and forth
between R (Reverse) and a forward
gear, spinning the wheels as little as
possible. To prevent transmission
wear, wait until the wheels stop
spinning before shifting gears.
Release the accelerator pedal while
shifting, and press lightly on the
accelerator pedal when the
transmission is in gear. Slowly
spinning the wheels in the forward
and reverse directions causes a
rocking motion that could free the
vehicle. If that does not get the
vehicle out after a few tries, it might
need to be towed out. Recovery
hooks can be used, if the vehicle
has them. If the vehicle does need
to be towed out, see Towing the
Vehicle on page 10‑93.

Black plate (30,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
9-30 Driving and Operating
Engine Coolant Heater
The engine heater can provide
easier starting and better fuel
economy during engine warm-up
in cold weather conditions at or
below−18°C (0°F). Vehicles with an
engine heater should be plugged in
at least four hours before starting.
An internal thermostat in the
plug-end of the cord may exist
which will prevent engine coolant
heater operation at temperatures
above −18°C (0°F).
If the vehicle has a diesel engine,
see the Duramax Diesel supplement
for more information.
To Use the Engine Coolant
Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord. The cord
is secured to the Engine
Compartment Fuse Block with
a clip. Carefully remove the wire tie which bundles the
electrical plug. Do not cut the
electrical cord.
3. Plug the cord into a normal, grounded 110-volt AC outlet.
{WARNING
Plugging the cord into an
ungrounded outlet could cause an
electrical shock. Also, the wrong
kind of extension cord could
overheat and cause a fire. You
could be seriously injured. Plug
the cord into a properly grounded
three-prong 110-volt AC outlet.
If the cord will not reach, use a
heavy-duty three-prong extension
cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and store the
cord as it was before to keep
it away from moving engine
parts. If you do not, it could be
damaged. The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer in the
area where you will be parking the
vehicle for the best advice on this.
Shifting Into Park
{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). So, be sure the
transfer case is in a drive
(Continued)

Black plate (31,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Driving and Operating 9-31
WARNING (Continued)
gear—not in N (Neutral). If you
are pulling a trailer, see Driving
Characteristics and Towing Tips
on page 9‑74.
1. Hold the brake pedal down, then set the parking brake.
See Parking Brake on page 9‑54
for more information.
2. Move the shift lever into the P (Park) position by pulling the
shift lever toward you and
moving it up as far as it will go.
3. Be sure the transfer case is in a drive gear —not in N (Neutral).
4. Turn the ignition key to LOCK/OFF.
5. Remove the key and take it with you. If you can leave the vehicle
with the ignition key in your
hand, the vehicle is in P (Park).
Leaving the Vehicle With the
Engine Running
{WARNING
It can be dangerous to leave the
vehicle with the engine running.
The vehicle could move suddenly
if the shift lever is not fully in
P (Park) with the parking brake
firmly set.
If you have four-wheel drive and
the transfer case is in N (Neutral),
the vehicle will be free to roll,
even if the shift lever is in
P (Park). So be sure the transfer
case is in a drive gear —not in
N (Neutral).
And, if you leave the vehicle
with the engine running, it could
overheat and even catch fire. You
or others could be injured. Do not
leave the vehicle with the engine
running unless you have to. If you have to leave the vehicle with
the engine running, be sure your
vehicle is in P (Park) and the
parking brake is firmly set before
you leave it. After you move the shift
lever into P (Park), hold the regular
brake pedal down. Then, see if you
can move the shift lever away from
P (Park) without first 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 your 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. To find out how,
Shifting Into Park on page 9‑30.

Black plate (34,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
9-34 Driving and Operating
Running the Vehicle
While Parked
It is better not to park with the
engine running. But if you ever have
to, here are some things to know.
{WARNING
Idling a vehicle in an enclosed
area with poor ventilation is
dangerous. Engine exhaust may
enter the vehicle. Engine exhaust
contains carbon monoxide (CO)
which cannot be seen or smelled.
It can cause unconsciousness
and even death. Never run the
engine in an enclosed area that
has no fresh air ventilation. For
more information, seeEngine
Exhaust on page 9‑33.
{WARNING
It can be dangerous to get out
of the vehicle if the automatic
transmission 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 unless you
have to. 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).
{WARNING
Four-wheel drive vehicles with
the transfer case in N (Neutral)
will allow the vehicle to roll, even
if the automatic transmission
shift lever is in P (Park). So, be
sure the transfer case is in a drive
gear —not in N (Neutral). Always
set the parking brake.
Follow the proper steps to be sure
the vehicle will not move. See
Shifting Into Park on page 9‑30.
If pulling a trailer, see Driving
Characteristics and Towing Tips on
page 9‑74.

Black plate (36,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
9-36 Driving and Operating
{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 Neutral. So,
be sure the transfer case is in a
drive gear, Two-Wheel Drive High
or Four-Wheel Drive High or
Four-Wheel Drive Low —not in
Neutral. See Shifting Into Park on
page 9‑30.
R (Reverse): Use this gear to
back up.
Notice: 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 on page 9‑15. N (Neutral):
In this position, the
engine does not connect with the
wheels. To restart when you are
already moving, use N (Neutral)
only. Also, use N (Neutral) when the
vehicle is being towed.
{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.
Notice: 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. D (Drive):
This position is for
normal driving. It provides the best
fuel economy. If you need more
power for passing, and you are:
.Going less than about 55 km/h
(35 mph), push the accelerator
pedal about halfway down.
.Going about 55 km/h (35 mph) or
more, push the accelerator all
the way down.
By doing this, the vehicle shifts
down to the next gear and has
more power.
D (Drive) can be used when towing
a trailer, carrying a heavy load,
driving on steep hills, or for off-road
driving. You might want to shift
the transmission to a lower gear
selection if the transmission shifts
too often.
Downshifting the transmission in
slippery road conditions could result
in skidding. See “Skidding”under
Loss of Control on page 9‑5.

Black plate (40,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
9-40 Driving and Operating
SeeTow/Haul Mode Light on
page 5‑26 andHill and Mountain
Roads on page 9‑12 for more
information.
Also see “Tow/Haul Mode” under
Towing Equipment on page 9‑94 for
more information.
Grade Braking (6-Speed
Automatic Transmission)
The Grade Braking shift modes can
be activated by pressing the button
on the end of the shift control lever.
While in Range Selection Mode,
Grade Braking is deactivated
allowing the driver to select a
desired range of gears.
Grade Braking is only active while
the Tow/Haul Mode is selected and
you are not in the Range Selection
Mode. See “Tow/Haul Mode” listed
previously and Manual Mode on
page 9‑38 for more information on the Range Selection Mode. Grade
Braking assists in maintaining
desired vehicle speeds when driving
on downhill grades by automatically
implementing a shift schedule that
utilizes the engine and transmission
to slow the vehicle. This reduces
wear on the braking system and
increases control of the vehicle.
Grade Braking monitors vehicle
speed, acceleration, engine torque
and brake pedal usage. Using this
information, it detects when the
truck is on a downhill grade and the
driver desires to slow the vehicle by
pressing the brake.
This feature is active when the
exhaust brake is enabled (if
equipped).
Also see
Towing Equipment on
page 9‑94 for more information.
Drive Systems
Four-Wheel Drive
If the vehicle has Four-Wheel Drive,
you can send the engine's driving
power to all four wheels for extra
traction. To get the most satisfaction
out of Four-Wheel Drive, you must
be familiar with its operation.
Read the following before using
Four-Wheel Drive. See the
appropriate text for the transfer
case in the vehicle.
Notice:Driving on clean, dry
pavement in Four-Wheel Drive
High or Four-Wheel Drive Low for
an extended period of time may
cause premature wear on the
vehicle's powertrain. Do not
drive on clean, dry pavement
in Four-Wheel Drive High or
Four-Wheel Drive Low for
extended periods of time.