
Black plate (1,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
2012 GMC Sierra Owner ManualM
In Brief. . . . . . . . . . . . . . . . . . . . . . . . 1-1
Instrument Panel . . . . . . . . . . . . . . 1-2
Initial Drive Information . . . . . . . . 1-8
Vehicle Features . . . . . . . . . . . . . 1-27
Performance and Maintenance . . . . . . . . . . . . . . . . 1-35
Keys, Doors, and Windows . . . . . . . . . . . . . . . . . . . . 2-1
Keys and Locks . . . . . . . . . . . . . . . 2-2
Doors . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9
Vehicle Security . . . . . . . . . . . . . . 2-11
Exterior Mirrors . . . . . . . . . . . . . . . 2-14
Interior Mirrors . . . . . . . . . . . . . . . . 2-18
Windows . . . . . . . . . . . . . . . . . . . . . 2-19
Roof . . . . . . . . . . . . . . . . . . . . . . . . . . 2-22
Seats and Restraints . . . . . . . . . 3-1
Head Restraints . . . . . . . . . . . . . . . 3-2
Front Seats . . . . . . . . . . . . . . . . . . . . 3-3
Rear Seats . . . . . . . . . . . . . . . . . . . 3-10 Safety Belts . . . . . . . . . . . . . . . . . . 3-12
Airbag System . . . . . . . . . . . . . . . . 3-21
Child Restraints . . . . . . . . . . . . . . 3-39
Storage . . . . . . . . . . . . . . . . . . . . . . . 4-1
Storage Compartments . . . . . . . . 4-1
Instruments and Controls . . . . 5-1
Controls . . . . . . . . . . . . . . . . . . . . . . . 5-2
Warning Lights, Gauges, and
Indicators . . . . . . . . . . . . . . . . . . . 5-11
Information Displays . . . . . . . . . . 5-30
Vehicle Messages . . . . . . . . . . . . 5-39
Vehicle Personalization . . . . . . . 5-48
Universal Remote System . . . . 5-56
Lighting . . . . . . . . . . . . . . . . . . . . . . . 6-1
Exterior Lighting . . . . . . . . . . . . . . . 6-1
Interior Lighting . . . . . . . . . . . . . . . . 6-7
Lighting Features . . . . . . . . . . . . . . 6-9 Infotainment System
. . . . . . . . . 7-1
Introduction . . . . . . . . . . . . . . . . . . . . 7-1
Radio . . . . . . . . . . . . . . . . . . . . . . . . . . 7-9
Audio Players . . . . . . . . . . . . . . . . 7-15
Rear Seat Infotainment . . . . . . . 7-37
Phone . . . . . . . . . . . . . . . . . . . . . . . . 7-48
Trademarks and License Agreements . . . . . . . . . . . . . . . . . 7-55
Climate Controls . . . . . . . . . . . . . 8-1
Climate Control Systems . . . . . . 8-1
Air Vents . . . . . . . . . . . . . . . . . . . . . 8-10
Driving and Operating . . . . . . . . 9-1
Driving Information . . . . . . . . . . . . . 9-2
Starting and Operating . . . . . . . 9-25
Engine Exhaust . . . . . . . . . . . . . . 9-33
Automatic Transmission . . . . . . 9-35
Drive Systems . . . . . . . . . . . . . . . . 9-40
Brakes . . . . . . . . . . . . . . . . . . . . . . . 9-53

Black plate (2,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
2012 GMC Sierra Owner ManualM
Ride Control Systems . . . . . . . . 9-55
Cruise Control . . . . . . . . . . . . . . . . 9-58
Object Detection Systems . . . . 9-61
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 9-68
Towing . . . . . . . . . . . . . . . . . . . . . . . 9-74
Conversions and
Add-Ons . . . . . . . . . . . . . . . . . . . 9-105
Vehicle Care . . . . . . . . . . . . . . . . . 10-1
General Information . . . . . . . . . . 10-2
Vehicle Checks . . . . . . . . . . . . . . . 10-4
Headlamp Aiming . . . . . . . . . . . 10-37
Bulb Replacement . . . . . . . . . . 10-39
Electrical System . . . . . . . . . . . . 10-43
Wheels and Tires . . . . . . . . . . . 10-50
Jump Starting . . . . . . . . . . . . . . . 10-88
Towing . . . . . . . . . . . . . . . . . . . . . . 10-93
Appearance Care . . . . . . . . . . . 10-98 Service and Maintenance
. . . 11-1
General Information . . . . . . . . . . 11-1
Maintenance Schedule . . . . . . . 11-3
Special Application
Services . . . . . . . . . . . . . . . . . . . . 11-8
Additional Maintenance and Care . . . . . . . . . . . . . . . . . . . . 11-9
Recommended Fluids,
Lubricants, and Parts . . . . . . 11-12
Maintenance Records . . . . . . . 11-16
Technical Data . . . . . . . . . . . . . . . 12-1
Vehicle Identification . . . . . . . . . 12-1
Vehicle Data . . . . . . . . . . . . . . . . . . 12-2 Customer Information
. . . . . . . 13-1
Customer Information . . . . . . . . 13-1
Reporting Safety Defects . . . . 13-17
Vehicle Data Recording and
Privacy . . . . . . . . . . . . . . . . . . . . 13-19
OnStar . . . . . . . . . . . . . . . . . . . . . . . 14-1
OnStar Overview . . . . . . . . . . . . . 14-1
OnStar Services . . . . . . . . . . . . . . 14-2
OnStar Additional
Information . . . . . . . . . . . . . . . . . . 14-5
Index . . . . . . . . . . . . . . . . . . . . . i-1

Black plate (1,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
In Brief 1-1
In Brief
Instrument Panel
Instrument Panel (Base/UplevelVersion) . . . . . . . . . . . . . . . . . . . . . 1-2
Instrument Panel (Premium Version) . . . . . . . . . . . . . . . . . . . . . 1-6
Initial Drive Information
Initial Drive Information . . . . . . . . 1-8
Remote Keyless Entry (RKE)System . . . . . . . . . . . . . . . . . . . . . . 1-8
Remote Vehicle Start . . . . . . . . . 1-9
Door Locks . . . . . . . . . . . . . . . . . . . 1-9
Windows . . . . . . . . . . . . . . . . . . . . . 1-10
Seat Adjustment . . . . . . . . . . . . . 1-11
Memory Features . . . . . . . . . . . . 1-14
Heated and Ventilated Seats . . . . . . . . . . . . . . . . . . . . . . . 1-15
Head Restraint Adjustment . . . . . . . . . . . . . . . . . 1-15 Safety Belts . . . . . . . . . . . . . . . . . . 1-16
Passenger Sensing
System . . . . . . . . . . . . . . . . . . . . . 1-16
Mirror Adjustment . . . . . . . . . . . . 1-16
Steering Wheel Adjustment . . . . . . . . . . . . . . . . . 1-19
Throttle and Brake Pedal Adjustment . . . . . . . . . . . . . . . . . 1-19
Interior Lighting . . . . . . . . . . . . . . 1-20
Exterior Lighting . . . . . . . . . . . . . 1-21
Windshield Wiper/Washer . . . . 1-21
Climate Controls . . . . . . . . . . . . . 1-22
Transmission . . . . . . . . . . . . . . . . 1-24
Four-Wheel Drive . . . . . . . . . . . . 1-25
Vehicle Features
Radio(s) . . . . . . . . . . . . . . . . . . . . . 1-27
Satellite Radio . . . . . . . . . . . . . . . 1-28
Portable Audio Devices . . . . . . 1-28
Bluetooth
®. . . . . . . . . . . . . . . . . . . 1-29
Steering Wheel Controls . . . . . 1-29
Cruise Control . . . . . . . . . . . . . . . 1-30 Navigation System . . . . . . . . . . . 1-30
Driver Information
Center (DIC) . . . . . . . . . . . . . . . 1-30
Rear Vision Camera (RVC) . . . . . . . . . . . . . 1-31
Ultrasonic Parking Assist . . . . 1-31
Power Outlets . . . . . . . . . . . . . . . 1-32
Universal Remote System . . . 1-32
Sunroof . . . . . . . . . . . . . . . . . . . . . . 1-33
Performance and Maintenance
StabiliTrak®System . . . . . . . . . 1-35
Tire Pressure Monitor . . . . . . . . 1-35
Engine Oil Life System . . . . . . 1-35
Fuel E85 (85% Ethanol) . . . . . 1-36
Driving for Better Fuel Economy . . . . . . . . . . . . . . . . . . . 1-36
Roadside Assistance Program . . . . . . . . . . . . . . . . . . . . 1-36
OnStar
®. . . . . . . . . . . . . . . . . . . . . 1-37

Black plate (35,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
In Brief 1-35
Performance and
Maintenance
StabiliTrak®System
If equipped, the vehicle has a
traction control system that limits
wheel spin and the StabiliTrak
system that assists with directional
control of the vehicle in difficult
driving conditions. Both systems
turn on automatically every time the
vehicle is started.
.To turn off traction control, press
and release
gon the instrument
panel. The appropriate DIC
message displays. See Ride
Control System Messages on
page 5‑44.
.To turn off both traction control
and StabiliTrak, press and
hold
guntilgilluminates and
the appropriate DIC message
displays. See Ride Control
System Messages on page 5‑44.
.Press and releasegagain to
turn on both systems.
For more information, see
StabiliTrak
®System on page 9‑55.
Tire Pressure Monitor
This vehicle may have a Tire
Pressure Monitor System (TPMS).
The TPMS warning light alerts you
to a significant loss in pressure of
one of the vehicle's tires. If the
warning light comes on, stop as
soon as possible and inflate the
tires to the recommended pressure
shown on the Tire and Loading
Information label. See Vehicle Load
Limits on page 9‑16. The warning
light will remain on until the tire
pressure is corrected. During cooler conditions, the low tire
pressure warning light may appear
when the vehicle is first started and
then turn off. This may be an early
indicator that the tire pressures are
getting low and the tires need to be
inflated to the proper pressure.
The TPMS does not replace normal
monthly tire maintenance. It is the
driver
’s responsibility to maintain
correct tire pressures.
See Tire Pressure Monitor System
on page 10‑60.
Engine Oil Life System
The engine oil life system calculates
engine oil life based on vehicle use
and, on most vehicles, displays a
DIC message when it is necessary
to change the engine oil and filter.
The oil life system should be reset
to 100% only following an oil
change.

Black plate (36,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
1-36 In Brief
Resetting the Oil Life System
To reset the Engine Oil Life System
on most vehicles:
1. Display OIL LIFE REMAININGon the DIC. If the vehicle does
not have DIC buttons, the
vehicle must be in P (Park) to
access this display.
2. Press and hold the SET/RESET button on the DIC, or the trip
odometer reset stem if the
vehicle does not have DIC
buttons, for more than
five seconds. The oil life will
change to 100%.
On all vehicles, the Engine Oil Life
System can be reset as follows:
1. Turn the ignition to ON/RUN with the engine off.
2. Fully press the accelerator pedal slowly three times within
five seconds.
3. Display OIL LIFE REMAINING on the DIC. If the display shows
100%, the system is reset. See
Engine Oil Life System on
page 10‑10.
Fuel E85 (85% Ethanol)
Vehicles that have a FlexFuel badge
and a yellow fuel cap can use either
unleaded gasoline or ethanol fuel
containing up to 85% ethanol (E85).
See Fuel E85 (85% Ethanol) on
page 9‑71. For all other vehicles,
use only the unleaded gasoline
described under Recommended
Fuel on page 9‑68.
Driving for Better Fuel
Economy
Driving habits can affect fuel
mileage. Here are some driving
tips to get the best fuel economy
possible.
.Avoid fast starts and accelerate
smoothly.
.Brake gradually and avoid
abrupt stops.
.Avoid idling the engine for long
periods of time.
.When road and weather
conditions are appropriate, use
cruise control.
.Always follow posted speed
limits or drive more slowly when
conditions require.
.Keep vehicle tires properly
inflated.
.Combine several trips into a
single trip.
.Replace the vehicle's tires with
the same TPC Spec number
molded into the tire's sidewall
near the size.
.Follow recommended scheduled
maintenance.
Roadside Assistance
Program
U.S.: 1-888-881-3302
TTY Users (U.S.): 1-888-889-2438
Canada: 1-800-268-6800
Mexico: 01-800-466-0801

Black plate (37,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
In Brief 1-37
As the owner of a new GMC, you
are automatically enrolled in the
Roadside Assistance program.
SeeRoadside Assistance Program
(U.S. and Canada) on page 13‑7 or
Roadside Assistance Program
(Mexico) on page 13‑9.
Roadside Assistance and OnStar
(U.S. and Canada)
If you have an active OnStar
subscription, press the
Qbutton
and the current GPS location will
be sent to an OnStar advisor who
will assess your problem, contact
Roadside Assistance, and relay
your exact location to get the help
you need. Online Owner Center (U.S. and
Canada)
The Online Owner Center is a
complimentary service that includes
online service reminders, vehicle
maintenance tips, online owner
manual, special privileges,
and more.
Sign up today at:
U.S.: gmc.com (click on
“Owners,”
then“Manage My
GMC/Owners Login”)
Canada: gmcowner.ca
OnStar®
If equipped, this vehicle has a
comprehensive, in-vehicle system
that can connect to a live Advisor
for Emergency, Security, Navigation,
Connection, and Diagnostic
Services. See OnStar Overview on
page 14‑1.

Black plate (38,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-38 Seats and Restraints
Q: What if I added a snow plow?Will it keep the airbags from
working properly?
A: We have designed our airbag
systems to work properly under
a wide range of conditions,
including snow plowing with
vehicles that have the optional
Snow Plow Prep Package
(RPO VYU). But do not change
or defeat the snow plow's
“tripping mechanism.” If you do,
it can damage your snow plow
and your vehicle, and it may
cause an airbag inflation.
Q: Because I have a disability, I have to get my vehicle
modified. How can I find out
whether this will affect my
airbag system?
A: If you have questions, call
Customer Assistance. The
phone numbers and addresses
for Customer Assistance are
in Step Two of the Customer
Satisfaction Procedure in
this manual. See Customer Satisfaction Procedure (U.S.
and Canada) on page 13‑3
or
Customer Satisfaction
Procedure (Mexico) on
page 13‑3.
In addition, your dealer and the
service manual have information
about the location of the airbag
sensors, sensing and diagnostic
module and airbag wiring.
Airbag System Check
The airbag system does not need
regularly scheduled maintenance or
replacement. Make sure the airbag
readiness light is working. See
Airbag Readiness Light on
page 5‑18.
Notice: If an airbag covering is
damaged, opened, or broken, the
airbag may not work properly. Do
not open or break the airbag
coverings. If there are any
opened or broken airbag covers,
have the airbag covering and/or
airbag module replaced. For
the location of the airbags, see Where Are the Airbags? on
page 3‑23. See your dealer for
service.
Replacing Airbag System
Parts after a Crash
{WARNING
A crash can damage the
airbag systems in the vehicle.
A damaged airbag system
may not work properly and
may not protect you and your
passenger(s) in a crash, resulting
in serious injury or even death.
To help make sure the airbag
systems are working properly
after a crash, have them
inspected and any necessary
replacements made as soon as
possible.

Black plate (15,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-15
Engine Oil Pressure
Gauge
Metric
English
The engine oil pressure gauge
shows the engine oil pressure
in kPa (kilopascals) or psi (pounds
per square inch) when the engine is
running.
Oil pressure can vary with engine
speed, outside temperature and oil
viscosity, but if readings are outside
the normal operating range, the oil
pressure light comes on. See
Engine Oil Pressure Light on
page 5‑28 for more information. A reading outside the normal
operating range can be caused by a
dangerously low oil level or some
other problem causing low oil
pressure. Check the vehicle's
oil as soon as possible. See
“OIL
PRESSURE LOW STOP ENGINE”
under Engine Oil Messages on
page 5‑42 andEngine Oil on
page 10‑7.
Notice: Lack of proper engine oil
maintenance can damage the
engine. Driving with the engine
oil low can also damage the
engine. The repairs would not be
covered by the vehicle warranty.
Check the oil level as soon as
possible. Add oil if required,
but if the oil level is within the
operating range and the oil
pressure is still low, have the
vehicle serviced. Always follow
the maintenance schedule for
changing engine oil.
If the vehicle has a diesel engine,
see the Duramax diesel supplement
for more information.