2009 HUMMER H2 Owners Manual

Driver Shift Control (DSC)
The vehicle has Driver Shift Control (DSC). DSC
controls the transmission and vehicle speed while driving
down hill or towing a trailer by allowing you to select
a desired range of gears.
To use this feature:
1. Move the shift lever to the M (Manual Mode).
This will force a downshift from the current gear,
for gears 3 through 6.
2. Press the (+) plus or (−) minus button on the left
side of the steering wheel, to select the desired
range of gears for current driving conditions.When in the M (Manual Mode) a number will display
next to the M, indicating the maximum available gear.
The DIC display will show the message MANUAL SHIFT
on the rst line and the maximum available gear will be
displayed on the second line. SeeDriver Information
Center (DIC) on page 3-46andDIC Operation and
Displays (Using DIC Buttons) on page 3-47orDIC
Operation and Displays (Using Trip Odometer Reset
Stem) on page 3-52for more information. The number
displayed in the DIC is the highest gear available.
The transmission will be limited to the gear selected and
lower gears. Shifting will occur normally while driving,
however the cluster will continue to display the maximum
available gear. Higher gears will not be available unless
the selection is changed to include higher gears using
the (+) plus button.
Grade Braking is not available when the Driver Shift
Control is active. SeeTow/Haul Mode on page 2-36and
Towing a Trailer on page 4-55for more information.
While using the DSC, cruise control and the tow/haul
mode can be used.
2-35

Tow/Haul Mode
The vehicle has 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 while towing or
hauling heavy loads.
Press the button located on the instrument panel to the
right of the steering wheel to turn tow/haul on or off. While
tow/haul is on, a light on the instrument panel cluster
comes on.
SeeTow/Haul Mode Light on page 3-44for more
information.
Also see “Tow Haul Mode” underTowing a Trailer on
page 4-55for more information.
Grade Braking
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 andAutomatic
Transmission Operation on page 2-32for 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.
Also seeTowing a Trailer on page 4-55for more
information.
2-36

Cruise Grade Braking
Cruise Grade Braking operates while Cruise Control
is engaged in Tow/Haul mode to assist in maintaining
vehicle speed under loaded vehicle conditions. Cruise
Grade Braking assists when driving on a downhill grade.
It maintains vehicle speed by automatically implementing
a shift schedule that uses the engine and the
transmission to slow the vehicle. If vehicle speed is
above the desired speed the transmission will downshift
to slow the vehicle. If vehicle speed is near or below
desired speed the trans will upshift, allowing vehicle
speed to increase.
While in the Range Select Mode (RSM) mode, cruise
grade braking is not available.
SeeAutomatic Transmission Operation on page 2-32.
Full-Time Four-Wheel Drive
The Full-Time Four-Wheel Drive transfer case is
designed to constantly send the engine’s driving power
to all four wheels for extra traction. To get the most
out of Full-Time Four-Wheel Drive, you must be familiar
with its operation.
Notice:Driving on pavement in Four-Wheel
High Lock or Four Wheel Low Lock for extended
periods may cause premature wear on the vehicle
powertrain and tires. Do not drive in Four-Wheel
High Lock or Four-Wheel Low Lock on pavement
for extended periods.
2-37

Transfer Case Dial
The transfer case dial is
located to the right of the
instrument panel cluster.
Use this switch to shift into
and out of the different
Full-Time Four-Wheel
Drive modes.
The transfer case is a part of the Full-Time Four-Wheel
Drive system and allows the following four different
modes of operation:
4
m(Full-Time Four-Wheel Drive):This setting is
used for driving in most street and highway situations.
It can be used for light or variable off-road conditions.
4
mQ(Four-Wheel-High Lock):Use this mode
when you need extra traction in most off-road situations
such as sand, mud, snow, or level, rocky trails.4
nQ(Four-Wheel-Low Lock):This mode delivers
extra torque to all four wheels and is used for extreme
off-road conditions. Choose Four-Wheel-Low Lock
while driving off-road in deep sand, mud, or snow and
climbing or descending steep hills.
When in this mode you can also choose to lock the rear
axle for additional traction in extreme off-road situations.
SeeLocking Rear Axle on page 4-10.
Notice:Operating the vehicle in
Four-Wheel-Low Lock above 50 mph (80 km/h)
for any extended period of time could cause damage
to the transfer case. Do not operate the vehicle in
Four-Wheel-Low Lock above 50 mph (80 km/h) for
extended periods.
{CAUTION:
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 2-42.
2-38

N (Neutral):Shift the transfer case to N (Neutral) only
when towing the vehicle. SeeRecreational Vehicle
Towing on page 4-50orTowing Your Vehicle on
page 4-50for more information.
Indicator lights in the dial show which mode you are in.
The indicator lights will come on briey when you turn on
the ignition and one will stay on. If the lights do not come
on, take the vehicle to your dealer/retailer for service.
An indicator light will ash while shifting the transfer case.
It will remain on when the shift is complete. If the transfer
case cannot make a requested shift, it will return to the
last chosen setting.
If the SERVICE 4WD message stays on, you should
take the vehicle to your dealer/retailer for service.
See “Service 4WD message” underDriver Information
Center (DIC) on page 3-46.
Shifting between Four-Wheel High and
Four-Wheel-High Lock
With the vehicle traveling less than 40 mph
(64 km/h), turn the dial to the Four-Wheel High or
Four-Wheel-High Lock position. The indicator light
on the dial will ash while shifting. It will remain on
when the shift is complete.
It may be necessary to drive backwards for a short
distance of 25 feet (7.5 m) to get the lock feature
to disengage.
Shifting into Four-Wheel-Low Lock
To shift into Four-Wheel-Low Lock, 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 Low Lock is to have the vehicle moving
1 to 2 mph (1.6 to 3.2 km/h). Turn the dial to the
Four-Wheel-Low Lock position. You must wait for the
Four-Wheel-Low Lock indicator light on the dial to stop
ashing and remain lit before shifting the transmission
in gear.
When the transfer case is shifted into the
Four-Wheel-Low Lock position a StabiliTrak
®indicator
light will come on to show that the system has been
turned off and a message will show in the DIC.
SeeDIC Warnings and Messages on page 3-56
for more information.
Notice:Shifting the transmission into gear before
the indicator light stops ashing could cause
damage to the transfer case. Always wait until the
indicator light stops ashing before putting the
transmission back in gear.
It is normal for the vehicle to have engagement noise
and bump when shifting between Four-Wheel Low Lock,
Full-Time Four-Wheel Drive or Four-Wheel-High Lock
ranges or from N (Neutral) with the engine running.
2-39

If the Four-Wheel-Low Lock position is selected when
the vehicle is in gear and/or moving, the Four-Wheel
Low Lock indicator light will ash for 15 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 15 seconds the transfer case
will return to the setting last chosen.
Shifting Out of Four-Wheel Low Lock
To shift from Four-Wheel-Low Lock to Full-Time
Four-Wheel Drive or Four-Wheel-High Lock, 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-Low Lock is to have the vehicle moving
1 to 2 mph (1.6 to 3.2 km/h). Turn the dial to the
Full-Time Four-Wheel Drive or Four-Wheel-High Lock
position. You must wait for the Full-Time Four-Wheel
Drive or Four-Wheel-High Lock indicator light to stop
ashing and remain lit before shifting the transmission
into gear.It is normal for the vehicle to have engagement noise
and bump when shifting between Four-Wheel Low Lock,
Full-Time Four-Wheel Drive or Four-Wheel-High Lock
ranges or from N (Neutral) with the engine running.
If the Full-Time Four-Wheel Drive or
Four-Wheel-High Lock position is selected when
the vehicle is in gear and/or moving, the Full-Time
Four-Wheel Drive or Four-Wheel-High Lock indicator
light will ash 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).
Notice:Shifting the transmission into gear before
the indicator light stops ashing could cause
damage to the transfer case. Always wait until the
indicator light stops ashing before putting the
transmission back in gear.
2-40

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. SeeParking Brake on page 2-42.
3. Start the vehicle or turn the ignition to ON/RUN.
4. Put the transmission in N (Neutral).
5. Shift the transfer case to Full-Time Four-Wheel
Drive.
6. Turn the transfer case dial clockwise to N (Neutral)
position. The transfer case will not shift to N (Neutral)
unless this position is held for 10 seconds. The
N (Neutral) light will come on and then the dial can
be slowly released. The dial will be in the Four-Wheel
Low Lock position but the transfer case will be in
N (Neutral) with the N (Neutral) light on.
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. Shift the transmission to N (Neutral) and turn the
ignition to ON/RUN with the engine off.
3. Turn the transfer case dial to Full-Time Four-Wheel
Drive, Four-Wheel High Lock or Four-Wheel
Low Lock.
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
ashing could damage the transfer case. To help
avoid damaging the vehicle, always wait for the
mode indicator lights to stop ashing before
shifting the transmission into gear.
5. Start the engine and shift the transmission to the
desired position.
2-41

Parking Brake
To set the parking brake, hold the regular brake pedal
down and push down the parking brake pedal.
A chime will activate and the warning light will ash
when the parking brake is applied and the vehicle
is moving at least 3 mph (5 km/h) for at least
three seconds.To release the parking brake, hold the regular brake
pedal down. Pull the bottom edge of the lever, located
above the parking brake pedal, with the parking brake
symbol, to release the parking brake.
If the ignition is on when the parking brake is released,
the brake system warning light will go off.
Notice:Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Make sure
that the parking brake is fully released and the brake
warning light is off before driving.
If you are towing a trailer and are parking on any hill,
seeTowing a Trailer on page 4-55.
2-42