2012 GMC SIERRA 1500 lock

Black plate (1,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-1
Vehicle Care
General Information
General Information . . . . . . . . . . 10-2
California Proposition65 Warning . . . . . . . . . . . . . . . . . 10-3
California Perchlorate Materials Requirements . . . . 10-3
Accessories and Modifications . . . . . . . . . . . . . . . 10-3
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 10-4
Hood . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . 10-6
Engine Oil . . . . . . . . . . . . . . . . . . . 10-7
Engine Oil Life System . . . . . 10-10
Automatic Transmission Fluid (4-Speed Transmission) . . . 10-11
Automatic Transmission Fluid (6-Speed
Transmission) . . . . . . . . . . . . . 10-14
Engine Air Cleaner/Filter . . . . 10-17
Cooling System . . . . . . . . . . . . 10-18
Engine Coolant . . . . . . . . . . . . . 10-19
Engine Overheating . . . . . . . . 10-22 Overheated Engine
Protection
Operating Mode . . . . . . . . . . . 10-24
Engine Fan . . . . . . . . . . . . . . . . . 10-24
Power Steering Fluid . . . . . . . 10-25
Washer Fluid . . . . . . . . . . . . . . . 10-26
Brakes . . . . . . . . . . . . . . . . . . . . . 10-27
Brake Fluid . . . . . . . . . . . . . . . . . 10-28
Battery . . . . . . . . . . . . . . . . . . . . . 10-30
Four-Wheel Drive . . . . . . . . . . . 10-30
Front Axle . . . . . . . . . . . . . . . . . . 10-31
Rear Axle . . . . . . . . . . . . . . . . . . 10-32
Noise Control System . . . . . . 10-34
Starter Switch Check . . . . . . . 10-35
Automatic Transmission Shift Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . 10-35
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . 10-35
Park Brake and P (Park) Mechanism Check . . . . . . . . 10-36
Wiper Blade Replacement . . . . . . . . . . . . . . 10-36
Glass Replacement . . . . . . . . 10-37
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . 10-37
Bulb Replacement
Bulb Replacement . . . . . . . . . . 10-39
Halogen Bulbs . . . . . . . . . . . . . . 10-39
Headlamps, Front Turn Signal, Sidemarker, and
Parking Lamps . . . . . . . . . . . . 10-39
Pick-Up Box Identification and Fender Marker
Lamps . . . . . . . . . . . . . . . . . . . . 10-40
Taillamps (Chassis Cab Models) . . . . . . . . . . . . . . . . . . . 10-40
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . 10-41
Center High-Mounted Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . 10-42
License Plate Lamp . . . . . . . . 10-42
Replacement Bulbs . . . . . . . . . 10-43
Electrical System
Electrical System Overload . . . . . . . . . . . . . . . . . . 10-43
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-44
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-44
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-48

Black plate (3,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-3
California Proposition
65 Warning
Most motor vehicles, including this
one, contain and/or emit chemicals
known to the State of California to
cause cancer and birth defects or
other reproductive harm. Engine
exhaust, many parts and systems,
many fluids, and some component
wear by-products contain and/or
emit these chemicals.
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag
initiators, safety belt pretensioners,
and lithium batteries contained in
Remote Keyless Entry transmitters,
may contain perchlorate materials.
Special handling may be necessary.
For additional information, see
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and
Modifications
Adding non‐dealer accessories or
making modifications to the vehicle
can affect vehicle performance and
safety, including such things as
airbags, braking, stability, ride and
handling, emissions systems,
aerodynamics, durability, and
electronic systems like antilock
brakes, traction control, and stability
control. These accessories or
modifications could even cause
malfunction or damage not covered
by the vehicle warranty.

Black plate (7,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-7
A.Engine Air Cleaner/Filter on
page 10‑17.
B. Coolant Surge Tank and Pressure Cap. See Cooling
System on page 10‑18.
C. Positive (+) Terminal. See Jump
Starting on page 10‑88.
D. Battery on page 10‑30.
E. Remote Negative (−) Terminal (Out of View). See Jump
Starting on page 10‑88.
F. Automatic Transmission Dipstick (Out of View). See
“Checking the Fluid Level”
under Automatic Transmission
Fluid (4-Speed Transmission)
on page 10‑11 orAutomatic
Transmission Fluid (6-Speed
Transmission) on page 10‑14.
G. Engine Oil Fill Cap. See “When
to Add Engine Oil” under
Engine Oil on page 10‑7. H. Engine Oil Dipstick (Out of
View). See “Checking Engine
Oil” under Engine Oil on
page 10‑7.
I. Engine Cooling Fan (Out of View). See Cooling System on
page 10‑18.
J. Power Steering Fluid Reservoir. See Power Steering Fluid on
page 10‑25.
K. Brake Master Cylinder Reservoir. See Brake Fluid on
page 10‑28.
L. Engine Compartment Fuse
Block on page 10‑44.
M. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid on
page 10‑26.
If the vehicle has a diesel engine
and/or an Allison Transmission, see
the Duramax Diesel Supplement.Engine Oil
For diesel engine vehicles, see
“Engine Oil” in the Duramax Diesel
Supplement.
To ensure proper engine
performance and long life, careful
attention must be paid to engine
oil. Following these simple, but
important steps will help protect
your investment:
.Always use engine oil approved
to the proper specification and of
the proper viscosity grade. See
“Selecting the Right Engine Oil”
in this section.
.Check the engine oil level
regularly and maintain the
proper oil level. See “Checking
Engine Oil” and“When to Add
Engine Oil” in this section.
.Change the engine oil at the
appropriate time. See Engine Oil
Life System on page 10‑10.
.Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.

Black plate (13,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-13
4. Check both sides of the dipstick,and read the lower level. The
fluid level must be in the COLD
area, below the cross-hatched
area, for a cold check or in the
HOT or cross-hatched area for a
hot check. Be sure to keep the
dipstick pointed down to get an
accurate reading.
5. If the fluid level is in the acceptable range, push the
dipstick back in all the way; then
flip the handle down to lock the
dipstick in place. Consistency of Readings
Always check the fluid level at least
twice using the procedure described
previously. Consistency (repeatable
readings) is important to maintaining
proper fluid level. If readings are still
inconsistent, contact the dealer.
How to Add Automatic
Transmission Fluid
Refer to
Recommended Fluids
and Lubricants on page 11‑12 to
determine what kind of transmission
fluid to use.
Using a funnel, add fluid down
the transmission dipstick tube only
after checking the transmission
fluid while it is hot. A cold check
is used only as a reference. If the
fluid level is low, add only enough of
the proper fluid to bring the level up
to the HOT area for a hot check.
It does not take much fluid,
generally less than 0.5 Liter
(1 Pint). Do not overfill. Notice:
Use of the incorrect
automatic transmission fluid
may damage the vehicle, and the
damages may not be covered by
the vehicle warranty. Always use
the automatic transmission fluid
listed in Recommended Fluids
and Lubricants on page 11‑12.
.After adding fluid, recheck the
fluid level as described under
“How to Check Automatic
Transmission Fluid,” earlier in
this section.
.When the correct fluid level is
obtained, push the dipstick back
in all the way; then flip the
handle down to lock the dipstick
in place.

Black plate (15,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-15
6. Using the TRANS TEMPreading, determine and
perform the appropriate check
procedure. If the TRANS TEMP
reading is not within the required
temperature ranges, allow the
vehicle to cool, or operate the
vehicle until the appropriate
transmission fluid temperature is
reached.
Cold Check Procedure
Use this procedure only as a
reference to determine if the
transmission has enough fluid to be
operated safely until a hot check
procedure can be made. The hot
check procedure is the most
accurate method to check the
fluid level. Perform the hot check
procedure at the first opportunity.
Use this cold check procedure
to check fluid level when the
transmission temperature is
between 27°C and 32°C
(80°F and 90°F).
1. Locate the transmission dipstick at the rear of the engine
compartment, on the passenger
side of the vehicle.
See Engine Compartment
Overview on page 10‑6 for more
information.
2. Flip the handle up, then pull out the dipstick and wipe it with a
clean rag or paper towel.
3. Install the dipstick by pushing it back in all the way; wait
three seconds, and then pull it
back out again.
4. Check both sides of the dipstick and read the lower level. Repeat
the check procedure to verify the
reading.5. If the fluid level is below theCOLD check band, add only
enough fluid as necessary to
bring the level into the COLD
band. It does not take much
fluid, generally less than 0.5 Liter
(1 Pint). Do not overfill.
6. Perform a hot check at the first opportunity after the
transmission reaches a normal
operating temperature between
71°C to 93°C (160°F to 200°F).
7. If the fluid level is in the acceptable range, push the
dipstick back in all the way,
then flip the handle down to
lock the dipstick in place.

Black plate (16,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
10-16 Vehicle Care
Hot Check Procedure
Use this procedure to check the
transmission fluid level when the
transmission fluid temperature
is between 71°C and 93°C
(160°F and 200°F).
The hot check is the most accurate
method to check the fluid level. The
hot check should be performed at
the first opportunity in order to verify
the cold check. The fluid level rises
as fluid temperature increases,
so it is important to ensure the
transmission temperature is within
range.
1. Locate the transmission dipstickat the rear of the engine
compartment, on the passenger
side of the vehicle. See
Engine Compartment
Overview on page 10‑6 for more
information.
2. Flip the handle up, then pull out the dipstick and wipe it with a
clean rag or paper towel.
3. Install the dipstick by pushing it back in all the way; wait
three seconds, and then pull it
back out again.
4. Check both sides of the dipstick and read the lower level. Repeat
the check procedure to verify the
reading.5. Safe operating level is within theHOT cross hatch band on the
dipstick. If the fluid level is not within the HOT band, and the
transmission temperature is
between 71°C and 93°C
(160°F and 200°F), add or drain
fluid as necessary to bring the
level into the HOT band. If the
fluid level is low, add only
enough fluid to bring the level
into the HOT band. It does not
take much fluid, generally less
than 0.5 L (1 pint). Do not
overfill.
6. If the fluid level is in the acceptable range, push the
dipstick back in all the way, then
flip the handle down to lock the
dipstick in place.
Consistency of Readings
Always check the fluid level at least
twice using the procedure described
previously. Consistency (repeatable
readings) is important to maintaining
proper fluid level. If readings are still
inconsistent, contact the dealer.

Black plate (21,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-21
How to Add Coolant to the
Coolant Surge Tank for
Gasoline Engines
If the vehicle has a diesel engine,
see“Cooling System” in the
Duramax Diesel Supplement for
the proper coolant fill procedure.
{WARNING
You can be burned if you spill
coolant on hot engine parts.
Coolant contains ethylene glycol
and it will burn if the engine parts
are hot enough. Do not spill
coolant on a hot engine.
Notice: This vehicle has a
specific coolant fill procedure.
Failure to follow this procedure
could cause the engine to
overheat and be severely
damaged.
{WARNING
An electric engine cooling fan
under the hood can start up even
when the engine is not running
and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.
{WARNING
Steam and scalding liquids from a
hot cooling system can blow out
and burn you badly. They are
under pressure, and if you turn
the coolant surge tank pressure
cap —even a little —they can
come out at high speed. Never
turn the cap when the cooling
system, including the coolant
surge tank pressure cap, is hot.
Wait for the cooling system and
coolant surge tank pressure cap
to cool if you ever have to turn
the pressure cap. If no coolant is visible in the surge
tank, add coolant as follows:
1. Remove the coolant surge tank
pressure cap when the cooling
system, including the coolant
surge tank pressure cap and
upper radiator hose, is no
longer hot.
Turn the pressure cap slowly
counterclockwise about one full
turn. If a hiss is heard, wait for
that to stop. A hiss means there
is still some pressure left.
2. Keep turning the pressure cap slowly, and remove it.

Black plate (35,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Vehicle Care 10-35
Starter Switch Check
{WARNING
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular brake.
See Parking Brake on
page 9‑54.
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral). If the vehicle starts in any other
position, contact your dealer for
service.Automatic Transmission
Shift Lock Control
Function Check
{WARNING
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface.
2. Firmly apply the parking brake. See Parking Brake on
page 9‑54.
Be ready to apply the regular
brake immediately if the vehicle
begins to move. 3. With the engine off, turn the
ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Ignition Transmission
Lock Check
While parked, and with the parking
brake set, try to turn the ignition to
LOCK/OFF in each shift lever
position.
.The ignition should turn to
LOCK/OFF only when the shift
lever is in P (Park).
.The ignition key should come
out only in LOCK/OFF.
Contact your dealer if service is
required.