engine HUMMER H3 2007 User Guide

Automatic Transmission Operation
The automatic transmission has a shift lever on
the console.
It features an electronic shift position indicator
within the instrument cluster. This display must be
powered anytime the shift lever is capable of
being moved out of PARK (P). This means that if
your key is turned off, but not in LOCK, there
will be a small current drain on your battery which
could discharge your battery over a period of
time. If you need to leave your key in the ignition
but not in LOCK for an extended period, it is
recommended that you disconnect the battery
cable from the battery to prevent discharging your
battery.
There are several different positions for your shift
lever.PARK (P):This position locks your rear wheels.
It is the best position to use when you start the
engine because your vehicle cannot move easily.
{CAUTION:
It is dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P)
with the parking brake rmly set. Your
vehicle can roll.
Do not leave your 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 your vehicle will not
move, even when you are on fairly level
ground, always set your parking brake and
move the shift lever to PARK (P).
SeeShifting Into Park (P) (Automatic
Transmission) on page 117. If you are
pulling a trailer, seeTowing a Trailer on
page 297.
106

Make sure the shift lever is fully in PARK (P)
before starting the engine. Your vehicle has an
automatic transmission shift lock control system.
You must fully apply your regular brakes rst
and then press the shift lever button before you
can shift from PARK (P) when the ignition key is in
ON. If you cannot shift out of PARK (P), ease
pressure on the shift lever and push the shift lever
all the way into PARK (P) as you maintain
brake application. Then press the shift lever button
and move the shift lever into another gear. See
Shifting Out of Park (P) (Automatic Transmission)
on page 119
REVERSE (R):Use this gear to back up.
Notice:Shifting to REVERSE (R) while your
vehicle is moving forward could damage
the transmission. The repairs would not be
covered by your warranty. Shift to
REVERSE (R) only after your vehicle is
stopped.
To rock your vehicle back and forth to get out of
snow, ice, or sand without damaging your
transmission, seeIf Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow on page 286.NEUTRAL (N):In this position, your engine does
not connect with the wheels. To restart when
you are already moving, use NEUTRAL (N) only.
{CAUTION:
Shifting into a drive gear while your
engine is running at high speed is
dangerous. Unless your foot is rmly on
the brake pedal, your vehicle could move
very rapidly. You could lose control and
hit people or objects. Do not shift into a
drive gear while your engine is running at
high speed.
Notice:Shifting out of PARK (P) or
NEUTRAL (N) with the engine running at high
speed may damage the transmission. The
repairs would not be covered by your warranty.
Be sure the engine is not running at high
speed when shifting your vehicle.
107

Manual Transmission Operation
This is your shift
pattern.
Here is how to operate your manual transmission:
FIRST (1):Press the clutch pedal and shift into
FIRST (1). Then, slowly let up on the clutch pedal
as you slowly press down on the accelerator pedal.
You can shift into FIRST (1) when you are going
less than 20 mph (30 km/h). If you have come to a
complete stop and it is hard to shift into FIRST (1),
put the shift lever in NEUTRAL and let up on the
clutch. Then press the clutch pedal back down and
shift into FIRST (1).SECOND (2):Press the clutch pedal as you
let up on the accelerator pedal and shift into
SECOND (2). Then, slowly let up on the clutch
pedal as you press the accelerator pedal.
THIRD, FOURTH AND FIFTH (3, 4 and 5):
Shift into THIRD (3), FOURTH (4) and FIFTH (5)
the same way you do for SECOND (2). 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 your engine.
109

Full-Time Four-Wheel Drive
Full-Time Four-Wheel Drive sends your 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.
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.You can choose between four 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 vehicle’s transfer case
to NEUTRAL only when towing your vehicle.
SeeRecreational Vehicle Towing on page 295
orTowing Your Vehicle on page 294for more
information.
Notice:Driving on pavement in Four-Wheel
High Lock or Four Wheel Low Lock for
extended periods may cause premature wear
on your vehicle’s powertrain and tires. Do not
drive in Four-Wheel High Lock or Four-Wheel
Low Lock on pavement for extended periods.
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.
111

Shifting into Four-Wheel Low Lock
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.
To shift into Four-Wheel-Low Lock, the ignition
must be in ON and the vehicle must be stopped or
moving less than 3 mph (5 km/h) with the
transmission in NEUTRAL (N). The preferred
method for shifting into Four-Wheel Low is to have
your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h).
Press and release the Four-Wheel-Low Lock
button. If your vehicle has a manual transmission,
the clutch pedal must be pressed to the oor 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
ashing and remain lit before shifting your
transmission in gear.
It is normal for your vehicle to have engagement
noise and bump when shifting between
Four-Wheel Low and Four-Wheel High ranges or
from NEUTRAL with the engine running.If the Four-Wheel-Low Lock button is pressed
when your vehicle is in gear and/or moving
too fast, the Four-Wheel-Low Lock indicator light
will ash for 15 seconds and not complete the shift
unless your vehicle is moving less than 3 mph
(5 km/h) and the transmission is in NEUTRAL (N).
After 15 seconds the transfer case will return to
the last chosen setting.
Shifting Out of Four-Wheel-Low Lock
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.
To shift out of Four-Wheel-Low Lock, your
vehicle must be stopped or moving less
than 3 mph (5 km/h) with the transmission
in NEUTRAL (N) and the ignition in ON.
The preferred method for shifting out of
Four-Wheel-Low Lock is to have your
vehicle moving 1 to 2 mph (1.6 to 3.2 km/h).
113

Press and release the Four-Wheel High or
Four-Wheel-High Lock button. If your vehicle has
a manual transmission, the clutch pedal must
be pressed to the oor 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
ashing and remain lit before shifting your
transmission into gear.
It is normal for your vehicle to have engagement
noise and bump when shifting between
Four-Wheel Low and Four-Wheel High ranges
or from NEUTRAL with the engine running.
If the Four-Wheel High or Four-Wheel-High Lock
button is pressed when your vehicle is in gear
and/or moving too fast, the Four-Wheel High
or Four-Wheel-High Lock indicator light will ash
for 15 seconds but will not complete the shift
unless your vehicle is moving less than 3 mph
(5 km/h) and the transmission is in NEUTRAL (N).Shifting Into NEUTRAL
To shift the transfer case to NEUTRAL, do the
following:
1. Set the parking brake.
2. Start the vehicle by turning the ignition to
START.
3. Put the transmission in NEUTRAL (N).
If your 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.
{CAUTION:
Shifting an all-wheel-drive vehicle’s
transfer case into NEUTRAL can cause
your vehicle to roll even if the automatic
transmission is in PARK (P) or the manual
transmission is in any gear. You or others
could be injured. Make sure the parking
brake is rmly set before you shift the
transfer case to NEUTRAL.
114

5. Simultaneously press and hold the Four-Wheel
High and Four-Wheel-Low Lock buttons for
10 seconds. The NEUTRAL light will come on
when the transfer case shift to NEUTRAL is
complete.
6. Press and hold the regular brake pedal and
Shift the transmission to REVERSE (R) for
one second, then shift the transmission for
one second to DRIVE (D) for an automatic
transmission, or FIRST (1) for vehicles have
a manual transmission and then let out the
clutch. This is to ensure the transfer case is
in NEUTRAL. If not, repeat this procedure
starting at Step 3.
7. Turn the engine off, by turning the key to ACC.
8. Place the transmission shift lever in PARK (P)
for an automatic transmission, or FIRST (1)
for vehicles that have a manual transmission.
9. Turn the ignition to LOCK.Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and apply the regular
brake pedal.
2. Shift the transmission to NEUTRAL (N) for an
automatic transmission, or press the clutch
pedal for vehicles that have a manual
transmission. Then turn the ignition to ON
with the engine off.
3. Press the button for the desired transfer
case shift position (Four-Wheel High,
Four-Wheel-High Lock or
Four-Wheel-Low Lock).
After the transfer case has shifted out of
NEUTRAL the light will go out.
4. Release the parking brake.
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.
5. You may start the engine and shift the
transmission to the desired position.
115

Shifting Into Park (P)
(Automatic Transmission)
{CAUTION:
It can be dangerous to get out of your
vehicle if the shift lever is not fully in
PARK (P) with the parking brake rmly
set. Your vehicle can roll. If you have left
the engine running, the vehicle can move
suddenly. You or others could be injured.
To be sure your vehicle will not move,
even when you are on fairly level ground,
use the steps that follow. If you are
pulling a trailer, seeTowing a Trailer on
page 297.
1. Hold the brake pedal down with your right foot
and set the parking brake.
{CAUTION:
With all-wheel drive, your vehicle will be
free to roll — even if your shift lever is in
PARK (P) — if your transfer case is in
NEUTRAL. So, be sure the transfer case is
in a drive gear, four-wheel high (4H) or
four-wheel low (4L) — not in NEUTRAL.
2. Move the shift lever into PARK (P) by pressing
the shift lever button and moving the lever as
far forward as it will go.
3. Turn the ignition key to LOCK.
4. Remove the key and take it with you. If you
can leave your vehicle with the key, your
vehicle is in PARK (P).
117

Leaving Your Vehicle With the Engine
Running (Automatic Transmission)
{CAUTION:
It can be dangerous to leave your vehicle
with the engine running. Your vehicle
could move suddenly if the shift lever is
not fully in PARK (P) with the parking
brake rmly set. And, if you leave the
vehicle with the engine running, it could
overheat and even catch re. You or
others could be injured. Do not leave your
vehicle with the engine running.
If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P)
and your parking brake is rmly set before you
leave it. After you have moved the shift lever into
PARK (P), hold the regular brake pedal down.
Then, see if you can move the shift lever
away from PARK (P) without rst pressing the shift
lever button. If you can, it means that the shift
lever was not fully locked into PARK (P).
Torque Lock (Automatic Transmission)
If you are parking on a hill and you do not shift
your transmission into PARK (P) properly,
the weight of the vehicle may put too much force
on the parking pawl in the transmission. You
may nd it difficult to pull the shift lever out
of PARK (P). This is called “torque lock.” To
prevent torque lock, set the parking brake and then
shift into PARK (P) properly before you leave
the driver’s seat. To nd out how, seeShifting Into
Park (P) (Automatic Transmission) on page 117.
When you are ready to drive, move the shift
lever out of PARK (P) 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, so you can pull the shift
lever out of PARK (P).
118

Engine Exhaust
{CAUTION:
Engine exhaust can kill. It contains the
gas carbon monoxide (CO), which you
cannot see or smell. It can cause
unconsciousness and death.
You might have exhaust coming in if:
Your exhaust system sounds strange
or different.
Your vehicle gets rusty underneath.
Your vehicle was damaged in a
collision.
CAUTION: (Continued)
CAUTION: (Continued)

Your vehicle was damaged when
driving over high points on the road
or over road debris.
Repairs were not done correctly.
Your vehicle or exhaust system has
been modied improperly.
If you ever suspect exhaust is coming into
your vehicle:
Drive it only with all the windows
down to blow out any CO; and
Have your vehicle xed immediately.
120