2010 GMC SIERRA Four wheel drive

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 3 mph
(5 km/h) 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 to 2 mph (1.6 to 3.2 km/h). 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).
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 press and hold the regular brake pedal. See Parking Brake
on
page 3‑50for more information.
3. Start the vehicle or turn the ignition to ON/RUN.
4. Shift the transmission to N (Neutral).
5. Shift the transfer case to Two-Wheel-Drive High.
6. Turn the transfer case dial clockwise to N (Neutral) until it stops and hold it there until the Neutral light
starts blinking. This will take at least 10 seconds.
Then slowly release the dial to the four low
position. The N (Neutral) light will come on when
the transfer case shift to N (Neutral) is complete.
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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/
retailer 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.
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.
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If the vehicle has StabiliTrak®, shifting into
Four-Wheel-Drive Low will turn Traction Control and
StabiliTrak
®off. See StabiliTrak®System on page 5‑6.
{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). See
Parking Brake on page 3‑50.
N (Neutral) : Shift the vehicle's transfer case to
N (Neutral) only when towing the vehicle. See
Recreational Vehicle Towing
on page 5‑43or Towing
Your Vehicleon page 5‑43for more information.
If the SERVICE 4–Wheel Drive message stays on,
you should take the vehicle to your dealer/retailer for
service. See “Service 4–Wheel Drive message” under
DIC Warnings and Messages on page 4‑65.
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.
Shifting Into Four-Wheel-Drive Low
When Four-Wheel-Drive Low is engaged, vehicle speed
should be kept below 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 3 mph (5 km/h) with the
transmission in N (Neutral). The preferred method for
shifting into Four-Wheel-Drive Low is to have the
vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Turn the
knob to the Four-Wheel-Drive Low position.
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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 3 mph (5 km/h) 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, AUTO or Two-Wheel-Drive
High, the vehicle must be stopped or moving less than
3 mph (5 km/h) 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 to 2 mph (1.6 to 3.2 km/h). 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 3 mph (5 km/h) and the transmission is in
N (Neutral).
3-48

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 3‑50for 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.
6. Turn the transfer case dial clockwise to N (Neutral) until it stops and hold it there until the N (Neutral)
light starts blinking. This will take at least
10 seconds. Then slowly release the dial to the
four low position. The N (Neutral) light will come on
when the transfer case shift to N (Neutral) is
complete.
7. If the engine is running, make sure that the transfer case is in N (Neutral) by shifting the transmission
to R (Reverse) for one second, then shift the
transmission to D (Drive) for one second.
8. Turn the ignition to ACC/ACCESSORY, which will turn the engine off. 9. Place the transmission shift lever in P (Park).
10. Release the parking brake prior to moving the vehicle.
11. Turn the ignition to LOCK/OFF.Shifting Out of Neutral
To shift out of N (Neutral) do the following: 1. Set the parking brake and apply the regular brake pedal.
2. Turn the ignition to ON/RUN with the engine off, and shift the transmission to N (Neutral).
3. Turn the transfer case dial to Two-Wheel-Drive High, Four-Wheel-Drive High, AUTO.
After the transfer case has shifted out of
N (Neutral), the N (Neutral) light will go out.
4. Release the parking brake prior to moving the vehicle.
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.
3-49

Shifting Into Park
{WARNING:
It can be 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. 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, use the steps that follow.
With four-wheel drive, if 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). If you are pulling a trailer, see Towing
a Trailer on page 5‑50.
1. Hold the brake pedal down, then set the parking brake.
See Parking Brake
on page 3‑50for more
information. 2. Move the shift lever into the P (Park) position by
pulling the shift lever toward you and moving it up
as far as it will go.
3. Be sure the transfer case is in a drive gear —not
in N (Neutral).
4. Turn the ignition key to LOCK/OFF.
5. Remove the key and take it with you. If you can leave the vehicle with the ignition key in your hand,
the vehicle is in P (Park).
3-51

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).
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, see
Shifting Into Park
on
page 3‑51.
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).
3-52

Running the Vehicle While Parked
It is better not to park with the engine running. But if you
ever have to, here are some things to know.
{WARNING:
Idling a vehicle in an enclosed area with poor
ventilation is dangerous. Engine exhaust may
enter the vehicle. Engine exhaust contains
Carbon Monoxide (CO) which cannot be seen or
smelled. It can cause unconsciousness and even
death. Never run the engine in an enclosed area
that has no fresh air ventilation. For more
information, seeEngine Exhaust on page 3‑54.
{WARNING:
It can be dangerous to get out of the vehicle if the
automatic transmission 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
(Continued)
WARNING: (Continued)
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).
{WARNING:
Four-wheel drive vehicles with the transfer case in
N (Neutral) will allow the vehicle to roll, even if the
automatic transmission shift lever is in P (Park).
So, be sure the transfer case is in a drive
gear—not in N (Neutral). Always set the
parking brake.
Follow the proper steps to be sure the vehicle will not
move. See Shifting Into Park on page 3‑51.
If pulling a trailer, see Towing a Trailer on page 5‑50.
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