2010 HUMMER H3 Owners Manual

Driving and Operating 9-41
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 9‑40.
{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 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
it is on fairly level ground, always
set the parking brake and move
the automatic transmission shift
lever to P (Park), or the manual
transmission shift lever to Neutral.
Follow the proper steps to be sure
the vehicle will not move. See
Shifting Into Park
on page 9‑37and Parking on page 9‑39.
If pulling a trailer, see Driving
Characteristics and Towing Tips
on
page 9‑70.
Automatic
Transmission
The automatic transmission has a
shift lever on the console.

9-42 Driving and Operating
It features an electronic shift
position indicator within the
instrument cluster.
There are several different positions
for the shift lever.
P (Park):This position locks the
rear wheels. It is the best position
to use when you start the engine
because the vehicle cannot move
easily.
{WARNING
It is 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.
Do not leave the vehicle when
the engine is running unless you
have to. 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,
always set the parking brake and
move the shift lever to P (Park).
See Shifting Into Park
on
page 9‑37
. If you are pulling a
trailer, see Driving Characteristics
and Towing Tips on page 9‑70. Make sure the shift lever is fully in
P (Park) before starting the engine.
The vehicle has an automatic
transmission shift lock control
system. You must fully apply the
regular brakes first and then press
the shift lever button before you can
shift from P (Park) when the ignition
key is in ON/RUN. If you cannot
shift out of P (Park), ease pressure
on the shift lever and push the shift
lever all the way into P (Park) as
you maintain brake application.
Then press the shift lever button
and move the shift lever into
another gear. See
Shifting Out of
Park on page 9‑38.
R (Reverse): Use this gear to
back up.
Notice: Shifting to R (Reverse)
while the vehicle is moving
forward could damage the
transmission. The repairs would
not be covered by the vehicle
warranty. Shift to R (Reverse) only
after the vehicle is stopped.

Driving and Operating 9-43
To rock the vehicle back and forth to
get out of snow, ice, or sand without
damaging the transmission, see
If the Vehicle is Stuck on page 9‑26.
N (Neutral):In this position, the
engine does not connect with the
wheels. To restart the engine when
the vehicle is already moving, use
N (Neutral) only.
{WARNING
Shifting into a drive gear while the
engine is running at high speed is
dangerous. Unless your foot is
firmly on the brake pedal, the
vehicle could move very rapidly.
You could lose control and hit
people or objects. Do not shift
into a drive gear while the engine
is running at high speed. Notice:
Shifting out of P (Park)
or N (Neutral) with the engine
running at high speed may
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Be sure the
engine is not running at high
speed when shifting the vehicle.
D (Drive): This position is for
normal driving. It provides the best
fuel economy. If you need more
power for passing, and you are:.Going less than about 55 km/h
(35 mph), push the accelerator
pedal about halfway down.
.Going about 55 km/h (35 mph) or
more, push the accelerator all
the way down. Downshifting the transmission in
slippery road conditions could result
in skidding, see
“Skidding”under
Loss of Control on page 9‑6.
D (Drive) can be used when towing
a trailer. You may want to shift
the transmission to 3 (Third) or,
if necessary, a lower gear if the
transmission shifts too often under
heavy loads or in hilly conditions.
3 (Third): This position is also
used for normal driving. However 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 or
winding roads, or when towing a
trailer, so there is less shifting
between gears, or when going down
a steep hill.

9-44 Driving and Operating
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.
1 (First): 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 will not shift into
first gear until the vehicle is going
slowly enough. 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.
Hill Start Assist
H3 and H3T vehicles have a Hill
Start Assist feature, which may be
useful when stopped on a grade.
See Braking
on page 9‑3for more
information.
Manual Transmission
This is the shift pattern.
Vehicles with a manual transmission
operate as described below:
1 (First): Press the clutch pedal
and shift into 1 (First). Then slowly
let up on the clutch pedal as
you slowly press down on the
accelerator pedal.

Driving and Operating 9-45
You can shift into 1 (First) when
you are going less than 30 km/h
(20 mph). If you have come to a
complete stop and it is hard to shift
into 1 (First), put the shift lever in
Neutral and let up on the clutch.
Then press the clutch pedal back
down and shift into 1 (First).
2 (Second):Press the clutch pedal
as you let up on the accelerator
pedal and shift into 2 (Second).
Then, slowly let up on the clutch
pedal as you press the accelerator
pedal.
3 (Third), 4 (Fourth) and 5 (Fifth):
Shift into 3 (Third), 4 (Fourth) and
5 (Fifth) the same way you do for
2 (Second). Slowly let up on the
clutch pedal as you press the
accelerator pedal.
To stop, let up on the accelerator
pedal and press the brake pedal.
Just before the vehicle stops, press
the clutch pedal and the brake
pedal, and shift to Neutral.
Neutral: Use this position when
you start or idle the engine. R (Reverse):
To back up, stop the
vehicle. Press the clutch pedal and
shift into R (Reverse). Slowly let up
on the clutch pedal as you press
the accelerator pedal. If it is hard
to shift, let the shift lever return to
Neutral and release the clutch
pedal. Then press the clutch again
and shift into R (Reverse). Do not
attempt to shift into the fifth gear
position prior to shifting into
R (Reverse). The transmission has
a lock out feature which prevents a
5 (Fifth) gear to R (Reverse) gear
shift.
Notice: Shifting to R (Reverse)
while the vehicle is moving
forward could damage the
transmission. The repairs would
not be covered by the vehicle
warranty. Shift to R (Reverse) only
after the vehicle is stopped.
Use R (Reverse), along with the
parking brake, for parking the
vehicle.Up-Shift Light
This light will show you when to shift
to the next higher gear for best fuel
economy.
When this light comes on, you
can shift to the next higher gear if
weather, road and traffic conditions
permit. For the best fuel economy,
accelerate slowly and shift when the
light comes on.
While you accelerate, it is normal
for the light to go on and off if you
quickly change the position of the
accelerator. Ignore the shift light
when you downshift.
Disregard the shift light when the
transfer case is in four-wheel low.
For more information, see Up-Shift
Light on page 5‑15.

9-46 Driving and Operating
Shift Speeds
{WARNING
If you skip a gear when you
downshift, you could lose control
of the vehicle. You could injure
yourself or others. Do not shift
down more than one gear at a
time when you downshift.
Hill Start Assist
H3 and H3T vehicles have a Hill
Start Assist feature, which may be
useful when stopped on a grade.
SeeBraking
on page 9‑3for more
information.
Drive Systems
Four-Wheel Drive
Full-Time Four-Wheel Drive sends
engine 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.
Transfer Case Buttons
The transfer case buttons are
located to the right of the instrument
panel cluster. Use these switches
to shift into and out of the different
Full-Time Four-Wheel Drive modes. 4
m(Four-Wheel High):
This
setting is used for driving in most
street and highway situations. You
can also use this setting for light or
variable off-road conditions.
N (Neutral): Shift the transfer case
to Neutral only when towing the
vehicle. See Driving Characteristics
and Towing Tips
on page 9‑70for
more information.
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.
4
m Q(Four-Wheel-High Lock):
Use this setting when you need
extra traction in most off-road
situations such as sand, mud,
snow or level, rocky trails.

Driving and Operating 9-47
Notice:Operating the vehicle
in Four-Wheel-Low Lock above
48 km/h (30 mph) for any
extended period of time could
cause damage to the transfer
case. Do not operate the vehicle
in Four-Wheel-Low Lock above
48 km/h (30 mph) for extended
periods.
4
n Q(Four-Wheel-Low Lock):
This setting delivers extra torque
to all four wheels and is used for
extreme off-road conditions.
If the vehicle has locking axles,
they can be locked for additional
traction in extreme off-road
situations. See Locking Rear Axle
on page 9‑54andLocking Front
Axle on page 9‑55.
Indicator lights in the buttons show
which setting the transfer case is
in. The indicator lights will come
on briefly when the ignition is in
ON/RUN. The If the lights do not
come on, take the vehicle to your
dealer for service. An indicator light will flash while shifting the transfer
case. If the transfer case cannot
make a requested shift, it will return
to the last chosen setting.
If the SERV 4WD message on the
Driver Information Center (DIC)
stays on, take the vehicle to your
dealer for service. See Service 4WD
message under
Driver Information
Center (DIC) on page 5‑18.
Shifting between Four-Wheel High
and Four-Wheel-High Lock
With the vehicle traveling less than
120 km/h (75 mph), press and
release the Four-Wheel High or
Four-Wheel-High Lock button.
It may be necessary to drive
backwards while turning for a
distance of 7.5 m (25 feet) to get
the lock feature to disengage.
Shifting into Four-Wheel Low Lock
Notice: Shifting the transmission
into gear before the indicator
light stops flashing could cause
damage to the transfer case. Always wait until the indicator
light stops flashing before putting
the transmission back in gear.
To shift into Four-Wheel-Low Lock,
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 Low is to have
the vehicle moving 1.6 to 3.2 km/h
(1 to 2 mph). Press and release
the Four-Wheel-Low Lock button.
If the vehicle has a manual
transmission, the clutch pedal must
be pressed to the floor while you
press the Four-Wheel-Low Lock
button, or the shift will not be
completed. You must wait for the
Four-Wheel-Low Lock indicator light
to stop flashing 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
and Four-Wheel High ranges or
from Neutral.

9-48 Driving and Operating
If the Four-Wheel-Low Lock button
is pressed when the vehicle is in
gear and/or moving too fast, the
Four-Wheel-Low Lock indicator light
will flash for 15 seconds and not
complete the shift.
Shifting Out of
Four-Wheel-Low Lock
Notice:Shifting the transmission
into gear before the indicator
light stops flashing could cause
damage to the transfer case.
Always wait until the indicator
light stops flashing before putting
the transmission back in gear.
To shift out of Four-Wheel-Low
Lock, 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-Low Lock is to have
the vehicle moving 1.6 to 3.2 km/h
(1 to 2 mph). Press and release
the Four-Wheel High or
Four-Wheel-High Lock button. If the vehicle has a manual
transmission, the clutch pedal
must be pressed to the floor while
you press the Four-Wheel High
or Four-Wheel-High Lock button,
or the shift will not be completed.
You must wait for the Four-Wheel
High or Four-Wheel-High Lock
indicator light to stop flashing
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
and Four-Wheel High ranges or
from Neutral.
If the Four-Wheel High or
Four-Wheel-High Lock button is
pressed when the vehicle is in
gear and/or moving too fast,
the Four-Wheel High or
Four-Wheel-High Lock indicator
light will flash for 15 seconds
but will not complete the shift.
Shifting Into Neutral
To shift the transfer case to Neutral:
1. Set the parking brake.
2. Start the vehicle.
3. Put the transmission in
N (Neutral). If the vehicle has a
manual transmission, press and
hold the clutch pedal down while
you perform Steps 5 through 9.
4. Shift the transfer case to Four-Wheel High.
{WARNING
Shifting an all-wheel-drive
vehicle's transfer case into
Neutral can cause the vehicle
to roll even if the automatic
transmission is in P (Park) or the
manual transmission is in any
gear. You or others could be
injured. Make sure the parking
brake is firmly set before you shift
the transfer case to Neutral.