2011 GMC SIERRA ECO mode

Black plate (49,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-49
M (Manual Mode):This position
is available on vehicles with the
Allison Transmission or Hydra-Matic
6-Speed transmission. It lets
drivers select the range of gears
appropriate for current driving
conditions. If the vehicle has this
feature, see “Range Selection
Mode” underManual Mode on
page 9‑50.
3 (Third): This position is also used
for normal driving. It reduces vehicle
speed more than D (Drive) without
using the brakes. You might choose
3 (Third) instead of D (Drive) when
driving on hilly, winding roads, when
towing a trailer, so there is less
shifting between gears and when
going down a steep hill.
2 (Second): This position reduces
vehicle speed even more than
3 (Third) without using the brakes.
You can use 2 (Second) on hills. It can help control vehicle speed as
you go down steep mountain roads,
but then you would also want to use
the brakes off and on.
If you manually select 2 (Second)
in an automatic transmission, the
transmission will start in second
gear. You can use this feature for
reducing the speed of the rear
wheels when you are trying to
start the vehicle from a stop on
slippery road surfaces.
1 (First):
For the Hydra-Matic
4-Speed transmission this position
reduces vehicle speed even more
than 2 (Second) without using the
brakes. You can use it on very steep
hills, or in deep snow or mud. If the
shift lever is put in 1 (First) while
the vehicle is moving forward, the
transmission does not shift into first
gear until the vehicle is going slowly
enough. For an Allison Transmission or
Hydra-Matic 6-Speed transmission,
this position reduces vehicle speed
without using the brakes. You can
use it for major/severe downgrades
and off-road driving where the
vehicle would otherwise accelerate
due to steepness of grade. When
you shift to 1 (First) it provides the
lowest gear appropriate to current
road speed and continues to
downshift as the vehicle slows,
eventually downshifting to
1 (First) gear.
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.

Black plate (51,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-51
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
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 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 is on, a light on the
instrument panel cluster will
come on.
See
Tow/Haul Mode Light on
page 5‑29 for more information.
Also see “Tow/Haul Mode” under
Towing Equipment on page 9‑112
for more information.

Black plate (57,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-57
When Using the Manual
Transfer Case
.Shifts into or out of Four-Wheel
Drive Low or N (Neutral) should
be made using quick motions to
avoid excessive gear grinding.
Shifting slowly may make it more
difficult to shift.
.You may notice that it is harder
to shift when the vehicle is cold.
After the vehicle warms up the
shifting will return to normal.
.While in Four-Wheel High or
Four-Wheel Drive Low you
may experience reduced fuel
economy.
.Avoid driving in Four-Wheel
Drive on clean, dry pavement.
It may cause your tires to wear
faster, make the transfer case
harder to shift, and run noisier.
.If the transfer case shifter is in
the N (Neutral) position and
you have difficulty reaching the
selected transfer case mode,
with the engine running, shift
the transmission momentarily
to D (Drive) and then back to
N (Neutral). This will realign the
gear teeth in the transfer case
and allow you to complete the
shift.
Shifting from Two-Wheel Drive
High to Four-Wheel Drive High
.Shifts between Two-Wheel Drive
High and Four-Wheel Drive High
can be made at any vehicle
speed.
.Shift the transfer case lever in
one continuous motion into
either the Four-Wheel Drive
High or Two-Wheel Drive
High position.
.Shifting from Two-Wheel Drive
High to Four-Wheel Drive High
while the vehicle is in motion
may require that moderate force
be applied to the shift lever for a
few seconds before Four-Wheel
Drive High can be engaged,
especially in cold weather.
.In extremely cold weather, it may
be necessary to slow or stop the
vehicle to shift into Four-Wheel
Drive High.
.While in Four-Wheel Drive High,
the vehicle can be driven at any
posted legal speed limit.

Black plate (61,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-61
Turn the knob to the Four-Wheel
Drive Low position. You must
wait for the Four-Wheel Drive
Low indicator light to stop flashing
and remain on before shifting the
transmission in gear.
Notice:Shifting the transmission
into gear before the requested
mode indicator light has stopped
flashing could damage the
transfer case. To help avoid
damaging the vehicle, always
wait for the mode indicator lights
to stop flashing before shifting
the transmission into gear.
It is typical for the vehicle to exhibit
significant engagement noise
and bump when shifting between
Four-Wheel Drive Low and
Four-Wheel Drive High ranges
or from transfer case N (Neutral)
with the engine running.
If the knob is turned to the
Four-Wheel Drive Low position
when the vehicle is in gear and/or
moving, the Four-Wheel Drive
Low indicator light will flash for 30 seconds and not complete the
shift unless the vehicle is moving
less than 5 km/h (3 mph) and the
transmission is in N (Neutral).
After 30 seconds the transfer
case will shift to Four-Wheel
Drive High mode.
Shifting Out of Four-Wheel
Drive Low
To shift from Four-Wheel Drive
Low to Four-Wheel Drive High,
or Two-Wheel Drive High, the
vehicle must be stopped or moving
less than 5 km/h (3 mph) with
the transmission in N (Neutral)
and the ignition in ON/RUN.
The preferred method for shifting
out of Four-Wheel Drive Low
is to have the vehicle moving
1.6 to 3.2 km/h (1 to 2 mph).
Turn the knob to the Four-Wheel
Drive High or Two-Wheel Drive
High position. You must wait
for the Four-Wheel Drive High or
Two-Wheel Drive High indicator
light to stop flashing and remain
on before shifting the transmission
into gear.Notice:
Shifting the transmission
into gear before the requested
mode indicator light has stopped
flashing could damage the
transfer case. To help avoid
damaging the vehicle, always
wait for the mode indicator lights
to stop flashing before shifting
the transmission into gear.
It is typical for the vehicle to exhibit
significant engagement noise
and bump when shifting between
Four-Wheel Drive Low and
Four-Wheel Drive High ranges
or from transfer case N (Neutral)
with the engine running.
If the knob is turned to the
Four-Wheel Drive High,
or Two-Wheel Drive High switch
position when the vehicle is in gear
and/or moving, the Four-Wheel
Drive High, or Two-Wheel Drive
High indicator light will flash for
30 seconds but will not complete the
shift unless your vehicle is moving
less than 3 mph (5 km/h) and the
transmission is in N (Neutral).

Black plate (63,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-63
Notice:Shifting the transmission
into gear before the requested
mode indicator light has stopped
flashing could damage the
transfer case. To help avoid
damaging the vehicle, always
wait for the mode indicator lights
to stop flashing before shifting
the transmission into gear.
5. Start the engine and shift the
transmission to the desired
position.
Excessively shifting the transfer
case into or out of the different
modes may cause the transfer case
to enter the shift protection mode.
This will protect the transfer case
from possible damage and will only
allow the transfer case to respond
to one shift per 10 seconds.
The transfer case may stay in this
mode for up to three minutes.Automatic Transfer Case
The transfer case knob is located
next to the steering column.
Use the dial to shift into and out of
Four-Wheel Drive. You can choose among five driving
settings:
Indicator lights in the dial
show which setting you are in.
The indicator lights will come on
briefly when you turn on the ignition
and one will stay on. If the lights do
not come on, you should take the
vehicle to your dealer for service.
An indicator light will flash while
shifting the transfer case. It will
remain illuminated when the shift
is complete. If for some reason
the transfer case cannot make a
requested shift, it will return to
the last chosen setting.
2
m(Two-Wheel Drive High):
This
setting is used for driving in most
street and highway situations.
The front axle is not engaged in
Two-Wheel Drive. This setting also
provides the best fuel economy.

Black plate (64,1)GMC Sierra Owner Manual - 2011
9-64 Driving and Operating
AUTO (Automatic Four-Wheel
Drive):This setting is ideal for
use when road surface traction
conditions are variable. When
driving the vehicle in AUTO,
the front axle is engaged, but the
vehicle's power is sent only to the
front and rear wheels automatically
based on driving conditions. Driving
in this mode results in slightly lower
fuel economy than Two-Wheel
Drive High.
4
m(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 9‑70.
{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 9‑69. N (Neutral):
Shift the vehicle's
transfer case to N (Neutral)
only when towing the vehicle.
See Recreational Vehicle Towing on
page 10‑103 orTowing the Vehicle
on page 10‑103 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.

Black plate (65,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-65
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.
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). Turn
the knob to the Four-Wheel Drive
Low position. You must wait for the
Four-Wheel Drive Low indicator
light to stop flashing and remain
on before shifting the transmission
into gear.
Notice:
Shifting the transmission
into gear before the requested
mode indicator light has stopped
flashing could damage the
transfer case. To help avoid
damaging the vehicle, always
wait for the mode indicator lights
to stop flashing before shifting
the transmission into gear. It is typical for the vehicle to
exhibit significant engagement
noise and bump when shifting
between Four-Wheel Drive Low
and Four-Wheel Drive High ranges
or from N (Neutral) with the engine
running.
If the knob is turned to the
Four-Wheel Drive Low position
when the vehicle is in gear and/or
moving, the Four-Wheel Drive
Low indicator light will flash for
30 seconds and not complete the
shift unless the vehicle is moving
less than 5 km/h (3 mph) and the
transmission is in N (Neutral).
After 30 seconds the transfer
case will shift to Four-Wheel
Drive High mode.

Black plate (66,1)GMC Sierra Owner Manual - 2011
9-66 Driving and Operating
Shifting Out of Four-Wheel
Drive Low
To shift from Four-Wheel Drive
Low to Four-Wheel Drive High,
AUTO or Two-Wheel Drive High,
the vehicle must be stopped or
moving less than 5 km/h (3 mph)
with the transmission in N (Neutral)
and the ignition in ON/RUN.
The preferred method for shifting
out of Four-Wheel Drive Low
is to have the vehicle moving
1.6 to 3.2 km/h (1 to 2 mph). Turn
the knob to the Four-Wheel Drive
High, AUTO or Two-Wheel Drive
High position. You must wait for
the Four-Wheel Drive High, AUTO
or Two-Wheel Drive High indicator
light to stop flashing and remain
on before shifting the transmission
into gear.
Notice:Shifting the transmission
into gear before the requested
mode indicator light has stopped
flashing could damage the transfer case. To help avoid
damaging the vehicle, always
wait for the mode indicator lights
to stop flashing before shifting
the transmission into gear.
It is typical for the vehicle to
exhibit significant engagement
noise and bump when shifting
between Four-Wheel Drive Low
and Four-Wheel Drive High ranges
or from N (Neutral) with the engine
running.
If the knob is turned to the
Four-Wheel Drive High, AUTO,
or Two-Wheel Drive High switch
position when the vehicle is in gear
and/or moving, the Four-Wheel
Drive High, AUTO or Two-Wheel
Drive High indicator light will flash
for 30 seconds but will not complete
the shift unless the vehicle is
moving less than 5 km/h (3 mph)
and the transmission is in
N (Neutral).
Shifting into Neutral
To shift the transfer case to
N (Neutral) do the following:
1. Make sure the vehicle is parked
so that it will not roll.
2. Set the parking brake and apply the regular brake pedal.
See Parking Brake on page 9‑69
for more information.
3. Shifting the transfer case into N (Neutral) can be done with
or without the engine running.
Shifting without the engine
running should be done with
the ignition in ON/RUN.
4. Put the transmission in N (Neutral).
5. Shift the transfer case to Two-Wheel Drive High.