2010 GMC YUKON HYBRID Owners Manual

2m(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 your vehicle in AUTO, the front
axle is engaged, but the vehicle's power is primarily
sent to the rear wheels. When the vehicle's software
determines a need for more traction, the system will
transfer more power to the front wheels. 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 high
position when you need extra traction, 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. The vehicle has StabiliTrak
®. Shifting into
Four-Wheel-Drive Low will turn Traction Control and
StabiliTrak
®off. See StabiliTrak®System in the index
of the Owner Manual for more information.
{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 in the index of the Owner Manual
for more information.
N (Neutral) : Shift the vehicle's transfer case to
N (Neutral) only when towing the vehicle. See
Recreational Vehicle Towing or Towing Your Vehicle in
the index of the Owner Manual.
If the SERVICE 4 WHEEL DRIVE message stays on,
you should take the vehicle to your dealer/retailer for
service. See DIC Warnings and Messages
on
page 4‑12for more information.
3-11

Shifting Into Four-Wheel Drive High or
AUTO (Automatic Four-Wheel Drive)
Turn the knob to the Four-Wheel 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 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” later in this
section for more information.
Shifting Into Four-Wheel Drive Low
When Four-Wheel Low is engaged, vehicle speed
should be kept below 40 mph (64 km/h). Extended
high-speed operation in 4L 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. 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 Four-Wheel Drive Low indicator light has
stopped flashing could damage the transfer case.
To help avoid damaging the vehicle, always wait for
the Four-Wheel Drive Low indicator light to stop
flashing before shifting the transmission into gear.
The vehicle may have significant engagement noise
and bump when shifting between Four-Wheel Drive Low
and Four-Wheel Drive High ranges or from N (Neutral)
while the engine is 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.
3-12

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 your 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 Four-Wheel Drive Low indicator light has
stopped flashing could damage the transfer case.
To help avoid damaging the vehicle, always wait for
the Four-Wheel Drive Low indicator light to stop
flashing before shifting the transmission into gear.
The vehicle may have significant engagement noise
and bump when shifting between Four-Wheel Drive Low
and Four-Wheel Drive High ranges or from N (Neutral)
while the engine is 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).
Shifting into Neutral
To shift the transfer case into N (Neutral):
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 in the index of the
Owner Manual for more information.
3. Start the vehicle or turn the ignition to 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‐Wheel Drive Low position. The N (Neutral)
light will come on when the transfer case shift to
N (Neutral) is complete.
3-13

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): 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 the desired transfer case shift position (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 Four-Wheel Drive Low indicator light has
stopped flashing could damage the transfer case.
To help avoid damaging the vehicle, always wait for
the Four-Wheel Drive Low indicator light 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.
3-14

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 5‑8. 1. Hold the brake pedal down, then set the parking
brake.
See Parking Brake in the index of the Owner
Manual for 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).
3-15

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 parking on a hill and the transmission not shifted 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 3‑15.
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).
3-16

Engine Coolant Heater
The engine coolant heater can provide easier starting
and better fuel economy during engine warm-up in cold
weather conditions at or below−18°C (0°F). Vehicles
with an engine heater should be plugged in at least
four hours before starting. An internal thermostat in
the plug-end of the cord may exist which will prevent
engine coolant heater operation at temperatures
above −18°C (0°F).
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The cord is secured to a wiring harness between
the engine and the Hybrid Auxiliary Underhood
Fuse Block with a clip. Carefully remove the wire
tie which secures the electrical cord. Do not cut the
electrical cord.
3. Plug the cord into a normal, grounded 110-volt AC outlet.
{WARNING:
Plugging the cord into an ungrounded outlet could
cause an electrical shock. Also, the wrong kind of
extension cord could overheat and cause a fire.
You could be seriously injured. Plug the cord into
a properly grounded three-prong 110-volt AC
outlet. If the cord will not reach, use a heavy-duty
three-prong extension cord rated for at least
15 amps.
4. Before starting the engine, be sure to unplug and store the cord as it was before to keep it away from
moving engine parts. If you do not, it could be
damaged.
The length of time the heater should remain plugged in
depends on several factors. Ask a dealer/retailer in the
area where you will be parking the vehicle for the best
advice on this.
3-17

Regenerative Braking
Regenerative braking is a hybrid technology that
enables the electric drive motor to operate as a
generator when coasting or braking. Energy from the
moving vehicle recharges the hybrid battery.
The hydraulic disc brakes work with the regenerative
braking to insure effective braking, such as when a high
braking demand is requested.
The braking system is computer controlled and blends
the regenerative braking with the conventional hydraulic
disc brakes to meet any requirements for deceleration.
The controller interprets the braking request and uses
regenerative braking, conventional hydraulic braking or
a combination of both as necessary. Because the
controller applies the hydraulic brakes through its high
pressure accumulator, you may occasionally hear the
motor driven pump when it recharges the system.
This is normal.
In the event of a controller problem, the brake pedal
may be harder to push and the stopping distance may
be longer.
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:
Exiting the vehicle, without first shifting into
P (Park), may cause the vehicle to move, and you
or others can be seriously injured. Because the
vehicle has the Automatic Engine Start/Stop
feature, the vehicle’s engine might seem to be
shut off when you come to a complete stop.
However, once the brake pedal is released,
the vehicle can move. The vehicle’s engine can
also restart at any time.
Shift to P (Park) and turn the ignition to
LOCK/OFF, before exiting the vehicle.
Follow the proper steps to be sure the vehicle will not
move. See “Shifting Into Park” in the owner manual for
more information.
If pulling a trailer, see Towing a Trailer
on page 5‑8for
more information.
3-18