
Black plate (1,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-1
Instruments and
Controls
Controls
Steering Wheel Adjustment . . . 5-2
Steering Wheel Controls . . . . . . 5-2
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Windshield Wiper/Washer . . . . . 5-4
Compass . . . . . . . . . . . . . . . . . . . . . 5-5
Clock . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Power Outlets . . . . . . . . . . . . . . . . . 5-9
Cigarette Lighter . . . . . . . . . . . . . 5-10
Ashtrays . . . . . . . . . . . . . . . . . . . . . 5-11
Warning Lights, Gauges, and
Indicators
Warning Lights, Gauges, andIndicators . . . . . . . . . . . . . . . . . . . 5-11
Instrument Cluster . . . . . . . . . . . 5-12
Speedometer . . . . . . . . . . . . . . . . 5-13
Odometer . . . . . . . . . . . . . . . . . . . . 5-13
Trip Odometer . . . . . . . . . . . . . . . 5-13
Tachometer . . . . . . . . . . . . . . . . . . 5-13
Fuel Gauge . . . . . . . . . . . . . . . . . . 5-14
Engine Oil Pressure Gauge . . . . . . . . . . . . . . . . . . . . . . 5-15 Engine Coolant Temperature
Gauge . . . . . . . . . . . . . . . . . . . . . . 5-16
Voltmeter Gauge . . . . . . . . . . . . . 5-16
Safety Belt Reminders . . . . . . . 5-17
Airbag Readiness Light . . . . . . 5-18
Airbag On-Off Light . . . . . . . . . . 5-19
Passenger Airbag Status Indicator . . . . . . . . . . . . . . . . . . . . 5-21
Charging System Light . . . . . . 5-22
Malfunction Indicator Lamp . . . . . . . . . . . . . 5-22
Brake System Warning Light . . . . . . . . . . . . . . . . . . . . . . . 5-25
Antilock Brake System (ABS) Warning Light . . . . . . . . . . . . . . 5-26
Four-Wheel-Drive Light . . . . . . 5-26
Tow/Haul Mode Light . . . . . . . . 5-26
StabiliTrak
®OFF Light . . . . . . . 5-27
Traction Control System (TCS)/StabiliTrak
®Light . . . . 5-27
Tire Pressure Light . . . . . . . . . . 5-27
Engine Oil Pressure Light . . . . 5-28
Low Fuel Warning Light . . . . . . 5-28
Security Light . . . . . . . . . . . . . . . . 5-29
High-Beam On Light . . . . . . . . . 5-29
Front Fog Lamp Light . . . . . . . . 5-29
Cruise Control Light . . . . . . . . . 5-30
Information Displays
Driver Information Center (DIC) . . . . . . . . . . . . . . . 5-30
Vehicle Messages
Vehicle Messages . . . . . . . . . . . 5-39
Battery Voltage and ChargingMessages . . . . . . . . . . . . . . . . . . 5-39
Brake System Messages . . . . 5-40
Door Ajar Messages . . . . . . . . . 5-40
Engine Cooling System Messages . . . . . . . . . . . . . . . . . . 5-41
Engine Oil Messages . . . . . . . . 5-42
Engine Power Messages . . . . 5-42
Fuel System Messages . . . . . . 5-43
Key and Lock Messages . . . . . 5-43
Lamp Messages . . . . . . . . . . . . . 5-43
Object Detection System Messages . . . . . . . . . . . . . . . . . . 5-43
Ride Control System Messages . . . . . . . . . . . . . . . . . . 5-44
Airbag System Messages . . . . 5-45
Anti-theft Alarm System Messages . . . . . . . . . . . . . . . . . . 5-45
Starting the Vehicle Messages . . . . . . . . . . . . . . . . . . 5-45
Tire Messages . . . . . . . . . . . . . . . 5-45

Black plate (30,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-30 Instruments and Controls
Cruise Control Light
For vehicles equipped with cruise
control, this light comes on
whenever the cruise control is set.
The light goes out when the cruise
control is turned off. SeeCruise
Control on page 9‑58 for more
information.
Information Displays
Driver Information
Center (DIC)
The vehicle has a Driver Information
Center (DIC).
The DIC displays information about
this vehicle. It also displays warning
messages if a system problem is
detected.
All messages will appear in
the DIC display located below the
tachometer in the instrument panel
cluster.
The DIC comes on when the ignition
is on. After a short delay, the DIC
will display the information that was
last displayed before the engine
was turned off. The DIC has different displays
which can be accessed by pressing
the DIC buttons located on the
instrument panel, next to the
steering wheel. If the vehicle does
not have DIC buttons, the trip
odometer reset stem can be used to
access some of the menu items.
The DIC displays trip, fuel, and
vehicle system information, and
warning messages if a system
problem is detected.
The DIC also allows some features
to be customized. See
Vehicle
Personalization (With DIC Buttons)
on page 5‑48 for more information.
If the vehicle has a diesel
engine, see the Duramax
®diesel
supplement for more information.

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 (12,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
9-12 Driving and Operating
.Have good tires with proper
tread depth. SeeTires on
page 10‑50.
.Turn off cruise control.
Highway Hypnosis
Always be alert and pay attention to
your surroundings while driving.
If you become tired or sleepy, find
a safe place to park the vehicle
and rest.
Other driving tips include:
.Keep the vehicle well ventilated.
.Keep the interior
temperature cool.
.Keep your eyes moving —scan
the road ahead and to the sides.
.Check the rearview mirror and
vehicle instruments often.
Hill and Mountain Roads
Driving on steep hills or through
mountains is different than driving
on flat or rolling terrain. Tips for
driving in these conditions include:
.Keep the vehicle serviced and in
good shape.
.Check all fluid levels and brakes,
tires, cooling system, and
transmission.
.Shift to a lower gear when going
down steep or long hills.
{WARNING
If you do not shift down, the
brakes could get so hot that they
would not work well. You would
then have poor braking or even
none going down a hill. You could
crash. Shift down to let the engine
assist the brakes on a steep
downhill slope.
{WARNING
Coasting downhill in N (Neutral)
or with the ignition off is
dangerous. The brakes will have
to do all the work of slowing down
and they could get so hot that
they would not work well. You
would then have poor braking or
even none going down a hill. You
could crash. Always have the
engine running and the vehicle in
gear when going downhill.

Black plate (13,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Driving and Operating 9-13
.Stay in your own lane. Do not
swing wide or cut across the
center of the road. Drive at
speeds that let you stay in your
own lane.
.Be alert on top of hills;
something could be in your lane
(stalled car, accident).
.Pay attention to special road
signs (falling rocks area, winding
roads, long grades, passing or
no-passing zones) and take
appropriate action.
Winter Driving
Driving on Snow or Ice
Drive carefully when there is snow
or ice between the tires and the
road, creating less traction or grip.
Wet ice can occur at about 0°C
(32°F) when freezing rain begins to
fall, resulting in even less traction.
Avoid driving on wet ice or in
freezing rain until roads can be
treated with salt or sand.
Drive with caution, whatever the
condition. Accelerate gently so
traction is not lost. Accelerating too
quickly causes the wheels to spin
and makes the surface under the
tires slick, so there is even less
traction.Try not to break the fragile traction.
If you accelerate too fast, the drive
wheels will spin and polish the
surface under the tires even more.
The
Antilock Brake System (ABS)
on page 9‑53 improves vehicle
stability during hard stops on
slippery roads, but apply the brakes
sooner than when on dry pavement.
Allow greater following distance on
any slippery road and watch for
slippery spots. Icy patches can
occur on otherwise clear roads in
shaded areas. The surface of a
curve or an overpass can remain icy
when the surrounding roads are
clear. Avoid sudden steering
maneuvers and braking while
on ice.
Turn off cruise control on slippery
surfaces.

Black plate (25,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Driving and Operating 9-25
Starting and
Operating
New Vehicle Break-In
Notice:The vehicle does not
need an elaborate break-in. But it
will perform better in the long run
if you follow these guidelines:
.Keep the vehicle speed at
88 km/h (55 mph) or less for
the first 805 km (500 miles).
.Do not drive at any one
constant speed, fast or
slow, for the first 805 km
(500 miles). Do not make
full-throttle starts. Avoid
downshifting to brake or
slow the vehicle.
.Avoid making hard stops for
the first 322 km (200 miles) or
so. During this time the new
brake linings are not yet
broken in. Hard stops with
new linings can mean
premature wear and earlier replacement. Follow this
breaking-in guideline every
time you get new brake
linings.
.Do not tow a trailer during
break-in. See
Trailer Towing
on page 9‑78 for the trailer
towing capabilities of the
vehicle and more
information.
Following break‐in, engine
speed and load can be gradually
increased.
Adjustable Throttle and
Brake Pedal
On vehicles with this feature, you
can change the position of the
throttle and brake pedals.
No adjustment to the pedals can
be made when the vehicle is in
R (Reverse) or while using cruise
control.
The control used to adjust the
pedals is located on the instrument
panel below the climate control
system.
Press the bottom of the control to
move the pedals closer. Press the
top of the control to move the
pedals away.
Before you start driving, fully
press the brake pedal to confirm
the adjustment is right for you.
While driving, make only small
adjustments.
The vehicle may have a memory
function which lets pedal settings be
saved and recalled. See Memory
Seats on page 3‑7.

Black plate (29,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Driving and Operating 9-29
Fast Idle System
If the vehicle has this feature it is
available only with cruise control.
The manual fast idle switch is
operated using the cruise control
buttons located on the left hand side
of the steering wheel.
This system can be used to
increase engine idle speed
whenever the following conditions
are met:
.The park brake is set.
.The brake pedal is not pressed.
.The vehicle must not be moving
and the accelerator must not be
pressed.
To control the fast idle:
.To enable the Fast Idle System,
press and release the Cruise
Control On/Off button and
ensure that the switch LED is lit.
.Press and release the Cruise
Control Set switch. Engine
speed will be held at
approximately 1200 RPM. When the fast idle is active the
Driver Information Center (DIC) will
display
“FAST IDLE ON.”
One of the following actions will turn
off the fast idle:
.Pressing the brake.
.Selecting the Cruise Control
Cancel button.
.Releasing the Parking Brake.
.The transmission shift lever is
moved out of P (Park) or
N (Neutral).
.Selecting the Cruise Control
On/Off button when it was
previously on.
.Pressing the Cruise Control Set
switch a second time.
.Pressing the accelerator greater
than a quarter of the way down.
.Turning the ignition switch to the
LOCK/OFF position.
Retained Accessory
Power (RAP)
The following vehicle accessories
can be used for up to 10 minutes
after the engine is turned off:
.Audio System
.Power Windows
.OnStar System (if equipped)
.Sunroof (if equipped)
These features work when
the key is in ON/RUN or ACC/
ACCESSORY. Once the key is
turned from ON/RUN to LOCK/OFF,
the windows and sunroof continue
to work up to 10 minutes until any
door is opened. The radio continues
to work for up to 10 minutes or until
the driver door is opened.

Black plate (39,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Driving and Operating 9-39
the plus/minus button located on the
steering column lever is used to
change to the gear.
Grade Braking is not available when
Range Selection Mode is active.
SeeTow/Haul Mode on page 9‑39.
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.
Notice: 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 your vehicle has the Allison
Transmission, or the Hydra-Matic
6-Speed Automatic Transmission, it
has a Low Traction Mode that can
assist in vehicle acceleration when
road conditions are slippery, such
as with ice or snow. While the
vehicle is at a stop, select the
second gear range using Range
Selection Mode. This will limit
torque to the wheels after it detects
wheel slip, preventing the tires from
spinning.
Tow/Haul Mode
4-Speed Automatic Transmission
6-Speed Automatic Transmission
Vehicles with an automatic
transmission have a Tow/Haul
Mode. The Tow/Haul Mode adjusts
the transmission shift pattern to
reduce shift cycling, providing
increased performance, vehicle
control, and transmission cooling
when driving down steep hills or
Mountain grades, towing, or hauling
heavy loads.
The selector button is located on
the end of the shift lever. Turn
the Tow/Haul Mode on and off by
pressing the button. When the
Tow/Haul Mode is enabled, a light
on the instrument panel cluster will
come on.