tow HUMMER H3 2010 Owner's Guide

9-34 Driving and Operating
Ignition Positions
The ignition switch has four different
positions.
To shift out of P (Park), turn the
ignition to ON/RUN and apply the
regular brake pedal.
Notice:Using a tool to force the
key to turn in the ignition could
cause damage to the switch or
break the key. Use the correct
key, make sure it is all the way in,
and turn it only with your hand.
If the key cannot be turned by
hand, see your dealer. (A) LOCK/OFF:
This position
locks the ignition. It also locks
the transmission on automatic
transmission vehicles. It locks
the steering wheel on manual
transmission vehicles. The key can
only be removed in LOCK/OFF.
On vehicles with an automatic
transmission, the shift lever must be
in P (Park) to turn the ignition switch
to LOCK/OFF.
The steering can bind with the
wheels turned off center. If this
happens, move the steering wheel
from right to left while turning the
key to ACC/ACCESSORY. If this
doesn't work, then the vehicle needs
service.
(B) ACC/ACCESSORY: This is the
position in which you can operate
the electrical accessories or items
plugged into the accessory power
outlets. On automatic transmission
vehicles, this position unlocks the
ignition. On manual transmission
vehicles, it unlocks the ignition and steering wheel. Use this position
if the vehicle must be pushed or
towed.
(C) ON/RUN:
This position can
be used to operate the electrical
accessories and to display some
instrument panel cluster warning
and indicator lights. The switch
stays in this position when the
engine is running. The transmission
is also unlocked in this position on
automatic transmission vehicles.
If you leave the key in the
ACC/ACCESSORY or ON/RUN
position with the engine off, the
battery could be drained. You may
not be able to start the vehicle if the
battery is allowed to drain for an
extended period of time.
(D) START: This is the position that
starts the engine. When the engine
starts, release the key. The ignition
switch returns to ON/RUN for
driving.

Driving and Operating 9-37
3. Plug it into a normal, grounded110-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 to prevent damage.
The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer in the
area where you will be parking the
vehicle for the best advice on this.
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. If you are pulling a
trailer, see Driving Characteristics
and Towing Tips on page 9‑70.
1. Hold the brake pedal down, then set the parking brake.
See Parking Brake
on
page 9‑51for more information.
{WARNING
With all-wheel drive, the vehicle
will be free to roll —even if the
shift lever is in P (Park) —if the
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 P (Park) by pressing the shift lever button
and moving the lever as far
forward as it will go.
3. Turn the ignition key to LOCK/OFF.
4. Remove the key from the ignition.

Driving and Operating 9-39
The shift lock release is always
functional except in the case of a
an uncharged or low voltage (less
than 9 volt) battery.
If the vehicle has an uncharged
battery or a battery with low voltage,
try charging or jump starting the
battery. SeeJump Starting
on
page 10‑86for more information.
To shift out of P (Park):
1. Apply the brake pedal.
2. Then press the shift lever button.
3. Move the shift lever to the desired position. If you still are unable to shift out
of P (Park):
1. Fully release the shift lever
button.
2. While holding down the brake pedal, press the shift lever
button again.
3. Move the shift lever to the desired position.
If you still cannot move the shift
lever from P (Park), consult your
dealer or a professional towing
service.
Parking
If the vehicle has a manual
transmission, before you get out of
the vehicle, move the shift lever into
R (Reverse), and firmly apply the
parking brake. Once the shift lever
has been placed into R (Reverse)
with the clutch pedal pressed in,
turn the ignition key to LOCK/OFF,
remove the key and release the
clutch.
If you are parking on a hill, or if
the vehicle is pulling a trailer, see
Driving Characteristics and Towing
Tips on page 9‑70.

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.

9-46 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 9-51
Parking Brake
The parking brake pedal is located
to the left of the regular brake pedal,
near the driver door.
To set the parking brake, hold the
regular brake pedal down, then
push the parking brake pedal down
to its fully-applied position.A chime will sound and the brake
warning light will flash when the
parking brake is applied and the
vehicle is moving at least 5 km/h
(3 mph) for at least three seconds.
See
Brake System Warning Light
on page 5‑14.
To release the parking brake, hold
the regular brake pedal down. Pull
the park brake release lever, located
above the parking brake pedal. 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 a hill, see Trailer Towing
on page 9‑74.
Brake Assist
This vehicle has a brake assist
feature designed to assist the
driver in stopping or decreasing
vehicle speed in emergency driving
conditions. This feature uses the
stability system hydraulic brake
control module to supplement
the power brake system under
conditions where the driver has
quickly and forcefully applied the
brake pedal in an attempt to quickly
stop or slow down the vehicle.

9-70 Driving and Operating
Towing
General Towing
Information
Only use towing equipment that
has been designed for the vehicle.
Contact your dealer or trailering
retailer for assistance with preparing
the vehicle for towing a trailer.
See the following trailer towing
information in this section:
.For information on driving while
towing a trailer, see“Driving
Characteristics and
Towing Tips”.
.For maximum vehicle and trailer
weights, see “Trailer Towing”.
.For information on equipment
to tow a trailer, see “Towing
Equipment”. For information on towing a disabled
vehicle, see
Towing the Vehicle
on
page 10‑90. For information on
towing the vehicle behind another
vehicle —such as a motorhome,
see Recreational Vehicle Towing
on
page 10‑90.
Driving Characteristics
and Towing Tips
{WARNING
The driver can lose control when
pulling a trailer if the correct
equipment is not used or the
vehicle is not driven properly.
For example, if the trailer is too
heavy, the brakes may not work
well —or even at all. The driver
and passengers could be
seriously injured. The vehicle
may also be damaged; the
resulting repairs would not be
covered by the vehicle warranty.
(Continued)
WARNING (Continued)
Pull a trailer only if all the steps in
this section have been followed.
Ask your dealer for advice and
information about towing a trailer
with the vehicle.
Notice: Pulling a trailer
improperly can damage the
vehicle and result in costly
repairs not covered by the
vehicle warranty. To pull a trailer
correctly, follow the advice in this
section and see your dealer for
important information about
towing a trailer with the vehicle.
The vehicle can tow a trailer when it
is equipped with the proper trailer
towing equipment. For trailering
capacity, see Trailer Towing
on
page 9‑74. Trailering changes
handling, acceleration, braking,
durability and fuel economy.

Driving and Operating 9-71
With the added weight, the engine,
transmission, wheel assemblies and
tires are forced to work harder and
under greater loads. The trailer also
adds wind resistance, increasing
the pulling requirements. For safe
trailering, correctly use the proper
trailering equipment.
The following information has
important trailering tips and rules
for your safety and that of your
passengers. Read this section
carefully before pulling a trailer.
Pulling A Trailer
Here are some important points:
.There are many laws, including
speed limit restrictions that apply
to trailering. Check for legal
requirements with state or
provincial police.
.Consider using a sway control.
See“Hitches” later in this
section.
.Do not tow a trailer at all during
the first 800 km (500 miles) the
new vehicle is driven. The
engine, axle or other parts could
be damaged.
.Then, during the first 800 km
(500 miles) that a trailer is
towed, do not drive over 80 km/h
(50 mph) and do not make starts
at full throttle. This helps the
engine and other parts of the
vehicle wear in at the heavier
loads.
.Vehicles with an automatic
transmission can tow in
D (Drive). Use a lower gear if
the transmission shifts too often.
For vehicles with a manual
transmission, it is better not to
use the highest gear.
.This vehicle has a Hill Start
Assist feature, which may be
useful when the vehicle is
stopped on a grade. See Hill
Start Assist (HSA)
on page 9‑52for more information.
.Do not drive faster than the
maximum posted speed for
trailers.
Driving with a Trailer
Towing a trailer requires experience.
Get familiar with handling and
braking with the added trailer
weight. The vehicle is now longer
and not as responsive as the
vehicle is by itself.
Check all trailer hitch parts and
attachments, safety chains,
electrical connectors, lamps, tires
and mirror adjustments. If the trailer
has electric brakes, start the vehicle
and trailer moving and then apply
the trailer brake controller by hand
to be sure the brakes are working.
During the trip, check occasionally
to be sure that the load is secure,
and the lamps and trailer brakes are
working properly.