Black plate (34,1)Chevrolet Silverado Owner Manual - 2012
9-34 Driving and Operating
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).
(Continued)
WARNING (Continued)
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 9‑33.
When you are ready to drive, move
the shift lever out of P (Park) before
you release the parking brake.
If torque lock does occur, you may
need to have another vehicle push
yours a little uphill to take some of
the pressure from the parking pawl
in the transmission, then you will be
able to pull the shift lever out of
P (Park).
Black plate (38,1)Chevrolet Silverado Owner Manual - 2012
9-38 Driving and Operating
Automatic
Transmission
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Vehicles with an automatic
transmission have an electronic shift
position indicator within the
instrument panel 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.
Hydra-Matic®4-Speed Automatic
Transmission
Heavy Duty 6-Speed Automatic
Transmission Shown (Light Duty 6‐Speed Similar)
See “Range Selection Mode” under
Manual Mode on page 9‑42.
P (Park): 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 effort to shift out of
P (Park). See “Torque Lock” under
Shifting Into Park on page 9‑33 for
more information.
{WARNING
It is 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.
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).
See Shifting Into Park on
page 9‑33. If you are pulling a
trailer, see Driving Characteristics
and Towing Tips on page 9‑82.
Black plate (42,1)Chevrolet Silverado Owner Manual - 2012
9-42 Driving and Operating
Manual Mode
Range Selection Mode
(Allison®Transmission or
Hydra-Matic®6-Speed
Transmission)
The vehicle may have a Range
Selection Mode. The Range
Selection Mode helps control the
vehicle's transmission and vehicle
speed while driving down hill or
towing a trailer by letting you select
a desired range of gears.
To use this feature, do the following:
1. Move the shift lever to
M (Manual Mode).
2. Press the plus/minus buttons, located on the steering column
shift lever, to select the desired
range of gears for current driving
conditions. When M (Manual Mode) is selected
a number displays next to the M,
indicating the current gear.
This number is the highest gear that
can be used. However, the vehicle
can automatically shift to lower
gears as it adjusts to driving
conditions. This means that all
gears below that number are
available. When 5 (Fifth) is selected,
1 (First) through 5 (Fifth) gears are
automatically shifted by the vehicle,
but 6 (Sixth) cannot be used until
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.
See
Tow/Haul Mode on page 9‑43.
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.
Black plate (43,1)Chevrolet Silverado Owner Manual - 2012
Driving and Operating 9-43
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.
See
Tow/Haul Mode Light on
page 5‑28 andHill and Mountain
Roads on page 9‑13 for more
information.
Also see “Tow/Haul Mode” under
Towing Equipment on page 9‑102
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 9‑42 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 9‑102 for more information.
Black plate (46,1)Chevrolet Silverado Owner Manual - 2012
9-46 Driving and Operating
Manual Transfer Case
The transfer case shift lever is on
the floor to the right of the driver.
Use this lever to shift into and out of
Four-Wheel Drive.
A Four-Wheel Drive indicator light
comes on when you shift into
four-wheel drive and the front axle
engages. SeeFour-Wheel-Drive
Light on page 5‑28. Some delay between shifting and
when the indicator light comes on is
normal.
Recommended Transfer Case Settings
Driving Conditions
Transfer Case Settings
2m 4m4n N
Normal YES Severe YES
Extreme YES
Vehicle in Tow* YES
*See Recreational Vehicle Towing on page 10‑97 orTowing the Vehicle on
page 10‑97.
Notice: Driving on clean, dry
pavement in four-wheel drive for
an extended period of time can
cause premature wear on the
vehicle's powertrain. Do not drive
on clean, dry pavement in
Four-Wheel Drive for extended
periods of time. 4
n(Four-Wheel Drive Low):
This setting also engages the front
axle and delivers extra torque. You
may never need Four-Wheel Drive
Low. It sends maximum power to
all four wheels. You might choose
Four-Wheel Drive Low if you are
driving off-road in deep sand, deep
mud, deep snow, and while climbing
or descending steep hills.
Black plate (51,1)Chevrolet Silverado Owner Manual - 2012
Driving and Operating 9-51
4m(Four-Wheel Drive High):Use
the Four-Wheel Drive High position
when extra traction is needed, such
as on snowy or icy roads or in most
off-road situations. This setting also
engages the front axle to help drive
the vehicle. This is the best setting
to use when plowing snow.
4
n(Four-Wheel Drive Low):
This setting also engages the front
axle and delivers extra torque.
You may never need this setting.
It sends maximum power to all
four wheels. You might choose
Four-Wheel Drive Low while driving
off-road in deep sand, deep mud,
deep snow, and while climbing or
descending steep hills.
If the vehicle has StabiliTrak
®,
shifting into Four-Wheel Drive Low
will turn Traction Control and
StabiliTrak off. See StabiliTrak
®
System on page 9‑62.
{WARNING
Shifting the transfer case to
N (Neutral) can cause the vehicle
to roll even if the transmission is
in P (Park). You or someone
else could be seriously injured.
Be sure to set the parking brake
before placing the transfer case in
N (Neutral). SeeParking Brake on
page 9‑60.
N (Neutral): Shift the vehicle's
transfer case to N (Neutral) only
when towing the vehicle. See
Recreational Vehicle Towing on
page 10‑97 orTowing the Vehicle
on page 10‑97 for more information.
If the SERVICE 4 WHEEL DRIVE
message stays on, you should
take the vehicle to your dealer
for service. See “SERVICE
4 WHEEL DRIVE message”
under Transmission Messages on
page 5‑50. Shifting Into Two-Wheel
Drive High
Turn the knob to the Two-Wheel
Drive High position. This can be
done at any speed, except when
shifting from Four-Wheel Drive Low.
See
“Shifting Out of Four-Wheel
Drive Low” for more information.
Shifting Into Four-Wheel
Drive Low
When Four-Wheel Drive Low is
engaged, vehicle speed should be
kept below 72 km/h (45 mph).
Extended high-speed operation in
Four-Wheel Drive Low may damage
or shorten the life of the drivetrain.
To shift to the Four-Wheel Drive
Low position, the ignition must be in
ON/RUN and the vehicle must be
stopped or moving less than 5 km/h
(3 mph) with the transmission in
N (Neutral). The preferred method
for shifting into Four-Wheel Drive
Low is to have the vehicle moving
1.6 to 3.2 km/h (1 to 2 mph).
Black plate (55,1)Chevrolet Silverado Owner Manual - 2012
Driving and Operating 9-55
4m(Four-Wheel Drive High):
Use the Four-Wheel Drive High
position when extra traction is
needed, such as on snowy or icy
roads or in most off-road situations.
This setting also engages the front
axle to help drive the vehicle.
This is the best setting to use when
plowing snow.
4
n(Four-Wheel Drive Low): This
setting also engages the front axle
and delivers extra torque. You may
never need this setting. It sends
maximum power to all four wheels.
You might choose Four-Wheel Drive
Low if you are driving off-road in
deep sand, deep mud, deep snow,
and while climbing or descending
steep hills.
If the vehicle has StabiliTrak
®,
shifting into Four-Wheel Drive Low
will turn Traction Control and
StabiliTrak off. See StabiliTrak
®
System on page 9‑62.
{WARNING
Shifting the transfer case to
N (Neutral) can cause the vehicle
to roll even if the transmission is
in P (Park). You or someone
else could be seriously injured.
Be sure to set the parking brake
before placing the transfer case in
N (Neutral). SeeParking Brake on
page 9‑60.
N (Neutral): Shift the vehicle's
transfer case to N (Neutral) only
when towing the vehicle. See
Recreational Vehicle Towing on
page 10‑97 orTowing the Vehicle
on page 10‑97 for more information.
If the SERVICE 4 WHEEL DRIVE
message stays on, you should
take the vehicle to your dealer
for service. See “SERVICE
4 WHEEL DRIVE message”
under Transmission Messages on
page 5‑50. Shifting Into Four-Wheel Drive
High or AUTO (Automatic
Four-Wheel Drive)
Turn the knob to the Four-Wheel
Drive High or AUTO position. This
can be done at any speed, except
when shifting from Four-Wheel
Drive Low. The indicator light will
flash while shifting. It will remain on
when the shift is completed.
Shifting Into Two-Wheel
Drive High
Turn the knob to the Two-Wheel
Drive High position. This can be
done at any speed, except when
shifting from Four-Wheel Drive Low.
The indicator light will flash while
shifting. It will remain on when the
shift is completed.
Black plate (114,1)Chevrolet Silverado Owner Manual - 2012
9-114 Driving and Operating
SERVICE TRAILER BRAKE
SYSTEM: This message
will be displayed when there is a
problem with the ITBC system.
If this message persists over
multiple ignition cycles, there is a
problem with the ITBC system.
Take the vehicle to an authorized
GM dealer to have the ITBC system
diagnosed and repaired.
If either the CHECK TRAILER
WIRING or SERVICE TRAILER
BRAKE SYSTEM message is
displayed while driving the vehicle,
power is no longer available to the
trailer brakes. When traffic
conditions allow, carefully pull the
vehicle over to the side of the road
and turn the ignition off. Check the
wiring connection to the trailer and
turn the ignition back on. If either of
these messages continues, either
the vehicle or trailer needs service.An authorized GM dealer may be
able to diagnose and repair
problems with the trailer. However,
any diagnosis and repair of the
trailer is not covered under the
vehicle warranty. Please contact
your trailer dealer for assistance
with trailer repairs and trailer
warranty information.
Trailer Sway
Control (TSC)
Non-hybrid vehicles with StabiliTrak
have a Trailer Sway Control (TSC)
feature. If the vehicle is towing a
trailer and the system detects that
the trailer is swaying, the vehicle
brakes are applied without the
driver pressing the brake pedal.
If the vehicle is equipped with the
Integrated Trailer Brake Control
(ITBC) system, StabiliTrak may
also apply the trailer brakes.
The TCS/StabiliTrak warning light
will flash on the instrument panel
cluster to notify the driver to reduce
speed. If the trailer continues to
sway, StabiliTrak will reduce engine
torque to help slow the vehicle.
See
StabiliTrak
®System on
page 9‑62 for more information.
Adding non‐dealer accessories can
affect the vehicle performance.
See Accessories and Modifications
on page 10‑3 for more information.