2010 GMC SIERRA transmission

7. If the engine is running, verify that the transfercase 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 the transfer case 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.
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.
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.
3-45

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.
3-47

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

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.
3-55

Cruise Control
{WARNING:
Cruise control can be dangerous where you
cannot drive safely at a steady speed. So, do not
use the cruise control on winding roads or in
heavy traffic.
Cruise control can be dangerous on slippery
roads. On such roads, fast changes in tire traction
can cause excessive wheel slip, and you could
lose control. Do not use cruise control on slippery
roads.
For vehicles with cruise control, a speed of about
40 km/h (25 mph) or more can be maintained without
keeping your foot on the accelerator. Cruise control
does not work at speeds below about 40 km/h (25 mph). When the brakes are applied, cruise control is
turned off.
For vehicles with an Allison
®or Hydra‐Matic 6‐speed
automatic transmission, see “Grade Braking and Cruise
Grade Braking (Allison Transmission) under Tow/Haul
Mode
on page 3‑34for an explanation of how cruise
control interacts with the Range Selection Mode,
tow/haul and grade braking systems.
For vehicles with the StabiliTrak
®system that begins
to limit wheel spin while you are using cruise control,
the cruise control will automatically disengage.
See StabiliTrak
®Systemon page 5‑6. When road
conditions allow the cruise control to be safely used
again, it can be turned back on.
4-7

Daytime Running Lamps (DRL)
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the day.
Fully functional daytime running lamps are required on
all vehicles first sold in Canada.
The DRL system comes on when the following
conditions are met:
.The ignition is on.
.The exterior lamps control is in AUTO.
.The engine is running.
.The light sensor determines it is daytime.
When the DRL system is on, only the DRL lamps are
on. The taillamps, sidemarker, instrument panel lights,
and other lamps will not be on.
When it begins to get dark, the automatic headlamp
system switches from DRL to the headlamps.
To turn off the DRL lamps, turn the exterior lamps
control to the OFF position and then release.
For vehicles first sold in Canada, the transmission
must be in the P (Park) position, before the DRL lamps
can be turned off.
Automatic Headlamp System
When it is dark enough outside, the automatic
headlamp system turns on the headlamps at the normal
brightness, along with the taillamps, sidemarker, parking
lamps, and the instrument panel lights. The radio lights
will also be dim.
To turn off the automatic headlamp system, turn the
exterior lamps switch to the off position and then
release it. For vehicles first sold in Canada, the
transmission must be in the P (Park) position, before
the automatic headlamp system can be turned off.
The vehicle has a light sensor located on the top of the
instrument panel in the defroster grille that regulates
when the automatic headlamps turn on. Do not cover
the sensor or the headlamps will come on whenever the
ignition is on.
The system may also turn on the headlamps when
driving through a parking garage or heavy overcast
weather. This is normal.
There is a delay in the transition between the daytime
and nighttime operation of the Daytime Running Lamps
(DRL) and the automatic headlamp systems so that
driving under bridges or bright overhead street lights
does not affect the system. The DRL and automatic
headlamp system is only affected when the light sensor
detects a change in lighting lasting longer than the
delay.
4-12