2007 HUMMER H2 Owners Manual

Towing
Towing Your Vehicle
Consult your dealer or a professional towing
service if you need to have your disabled vehicle
towed. SeeRoadside Assistance Program on
page 542.
If you want to tow your vehicle behind another
vehicle for recreational purposes (such as behind
a motorhome), see “Recreational Vehicle
Towing” following.
Recreational Vehicle Towing
Recreational vehicle towing means towing your
vehicle behind another vehicle – such as behind a
motorhome. The two most common types of
recreational vehicle towing are known as “dinghy
towing” (towing your vehicle with all four wheels
on the ground) and “dolly towing” (towing
your vehicle with two wheels on the ground and
two wheels up on a device known as a “dolly”).With the proper preparation and equipment, many
vehicles can be towed in these ways. See “Dinghy
Towing” and “Dolly Towing,” following.
Here are some important things to consider before
you do recreational vehicle towing:
What’s the towing capacity of the towing
vehicle? Be sure you read the tow vehicle
manufacturer’s recommendations.
How far will you tow? Some vehicles have
restrictions on how far and how long they
can tow.
Do you have the proper towing equipment?
See your dealer or trailering professional
for additional advice and equipment
recommendations.
Is your vehicle ready to be towed? Just as
you would prepare your vehicle for a long
trip, you’ll want to make sure your vehicle is
prepared to be towed. SeeBefore Leaving on
a Long Trip on page 349.
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Dinghy Towing
Use the following procedure to tow your vehicle:
1. Shift the transmission to PARK (P).
2. Turn the engine off, but leave the ignition in
ACCESSORY.
3. Firmly set the parking brake.
4. Securely attach the vehicle being towed to the
tow vehicle.
{CAUTION:
Shifting a full-time four-wheel-drive
vehicle’s transfer case into NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or others
could be injured. Make sure the parking
brake is rmly set before you shift the
transfer case to NEUTRAL.
5. Shift the transfer case to NEUTRAL (N).
SeeFull-Time Four-Wheel Drive on
page 128for the proper procedure to select
the NEUTRAL position for your vehicle.6. Release the parking brake only after the
vehicle being towed is rmly attached to
the towing vehicle. You can use your vehicle’s
front mounted receiver with the proper
accessories to tow it. See “Front Mounted
Receiver” underIf Your Vehicle is Stuck
in Sand, Mud, Ice, or Snow on page 357.
7. Turn the ignition to ACCESSORY.
8. Disconnect the battery if you are going to tow
for long distances or long periods of time.
When towing your vehicle for extended periods of
time, start your vehicle as often as possible to
prevent battery drain. This should only be
done when the tow vehicle is parked.
Dolly Towing
Your vehicle cannot be dolly towed. If you must
tow your vehicle behind another, use the
dinghy towing procedure listed previously.
Notice:Dolly towing your vehicle will damage
drivetrain components. Do not dolly tow
your vehicle.
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Selectable Extended Rear Ride
Height
If your vehicle has this feature it comes as part
of the electronically controlled air suspension
system.
The selectable rear ride height allows you to raise
the rear of the vehicle about 2 inches (5 cm)
over the normal ride height. This can be helpful
when driving off-road where you may need
more ground clearance to clear an obstacle.
The button that controls
this feature is located
on the instrument panel
to the right of the
steering wheel.To use this feature, ensure that the following
conditions are met:
The engine must be running.
All doors must be fully closed. The suspension
will not raise or lower if a door is open.
The vehicle speed must be less than 40 mph
(64 km/h). The system will not activate
otherwise.
Press the height control button to raise the rear of
the vehicle.
A light in the button will begin to ash as the rear
of the vehicle rises. Once the extended height
has been reached (this may take up to a minute),
the warning light will stop ashing and will stay
lit while the vehicle is at the extended height.
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To lower the vehicle to the normal ride height,
press the button again. The light in the button will
ash as the suspension lowers. When the light
in the button stops ashing and goes out,
the suspension has reached the normal ride
height.
This feature will lower the vehicle to the normal
height if vehicle speed exceeds 40 mph (64 km/h).
You may also want to use this feature when
ascending, descending or cresting a steep hill as
this can help prevent the rear bumper from
dragging on the base of the hill or prevent the
vehicle from grounding out (high centering) on the
crest of the hill.
Do not use this feature when towing a trailer.Electronically Controlled Air
Suspension System
The electronically controlled air suspension, if
equipped, keeps the rear of your vehicle level as
you load and unload it. The system includes a
compressor, two height sensor and two air springs
supporting the vehicle.
The engine must be running for the system to
level the vehicle after loading or unloading.
The system will suspend transitioning between
the designed ride height and the extended
ride height if any of the doors are open. However,
the system will not suspend operation during
normal leveling and once the doors are closed,
system leveling will continue.
You may hear the compressor running when you
load your vehicle, and periodically as the system
adjusts the vehicle to the standard ride height.
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You may also hear the release of air similar to a
hissing sound during suspension operation.
This is normal.
Load leveling will not function normally with the
inator hose attached to the inator outlet.
Remove the inater hose from the outlet when
it is not in use. SeeAccessory Inator on
page 466.
Overload and Overheat Protection
Overload protection is designed to protect the air
suspension system and is an indication to the
driver that the vehicle is overloaded.
If the rear suspension remains at a low height, the
rear axle load has exceeded GAWR (Gross Axle
Weight Rating). When the overload protection
mode is activated, the compressor operates forabout 30 seconds to one minute without raising the
vehicle depending on the amount of overload.
This will continue each time the ignition is turned on
until the rear axle load is reduced below GAWR.
If the total rear GAWR (Gross Axle Weight Rating)
is reached, the suspension may be slightly less
than level. This is normal and does not mean there
is a problem with the air suspension.
If the system overheats due to normal operation,
the SERVICE AIR SUSPENSION message
will not be displayed on the DIC, but the system
will shut down and stop all leveling functions until it
cools down. If the system overheats and sets
the SERVICE AIR SUSPENSION message in the
DIC, then there is a fault. SeeDIC Warnings
and Messages on page 226for more information.
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Towing a Trailer
{CAUTION:
If you do not use the correct equipment
and drive properly, you can lose control
when you pull a trailer. For example, if the
trailer is too heavy, the brakes may not
work well — or even at all. You and your
passengers could be seriously injured.
Pull a trailer only if you have followed all
the steps in this section. Ask your dealer
for advice and information about towing a
trailer with your vehicle.Notice:Pulling a trailer improperly can
damage your vehicle and result in costly repairs
not covered by your warranty. To pull a trailer
correctly, follow the advice in this part, and see
your dealer for important information about
towing a trailer with your vehicle.
To identify the trailering capacity of your vehicle,
you should read the information in “Weight of
the Trailer” that appears later in this section.
Trailering is different than just driving your vehicle
by itself. Trailering means changes in handling,
acceleration, braking, durability and fuel economy.
Successful, safe trailering takes correct
equipment, and it has to be used properly.
That’s the reason for this part. In it are many
time-tested, important trailering tips and safety
rules. Many of these are important for your safety
and that of your passengers. So please read
this section carefully before you pull a trailer.
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If You Do Decide To Pull A Trailer
If you do, here are some important points:
There are many different laws, including speed
limit restrictions, having to do with trailering.
Make sure your rig will be legal, not only
where you live but also where you’ll be driving.
A good source for this information can be
state or provincial police.
Consider using a sway control. See “Hitches”
later in this section.
Don’t tow a trailer at all during the rst
500 miles (800 km) your new vehicle is driven.
Your engine, axle or other parts could be
damaged.
Then, during the rst 500 miles (800 km) that
you tow a trailer, don’t drive over 50 mph
(80 km/h) and don’t make starts at full throttle.
This helps your engine and other parts of
your vehicle wear in at the heavier loads.
You can tow in DRIVE (D). You may want to
shift the transmission to THIRD (3) or, if
necessary, a lower gear selection if the
transmission shifts too often (e.g., under heavy
loads and/or hilly conditions). See “Tow/Haul
Mode” following.
Three important considerations have to do with
weight:
the weight of the trailer
the weight of the trailer tongue
and the weight on your vehicle’s tires
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Tow/Haul Mode
Tow/haul mode is used when using your vehicle to
pull a large or heavy load or trailer. Tow/haul is
also useful while pulling a load in rolling terrain, in
stop-and-go traffic, or when you need improved
low-speed control, such as when parking.
The purpose of the tow/haul mode is to do the
following:
Reduce the frequency and improve the
predictability of transmission shifts when
pulling a heavy trailer or a large or heavy load.
Provide the same solid shift feel when pulling a
heavy trailer or a large or heavy load as when
the vehicle is unloaded.
Improve control of vehicle speed while requiring
less accelerator pedal activity when pulling a
heavy trailer or a large or heavy load.
Tow/haul mode is most effective when the vehicle
and trailer combined weight is at least 75 percent of
the vehicle’s Gross Combination Weight Rating
(GCWR). See “Weight of the Trailer” later in this
section.Press the button on the
instrument panel to the
right of the steering
wheel to enable
the tow/haul mode.
A light on the instrument
panel will illuminate to
indicate that tow/haul
mode has been
selected.
Press the button again to turn off tow/haul mode.
The indicator light on the instrument panel will
turn off. The vehicle will automatically turn
off tow/haul mode every time it is started.
Driving with tow/haul mode activated without a
heavy load or with no trailer will cause reduced
fuel economy and unpleasant engine and
transmission driving characteristics, but will not
cause damage.
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