HUMMER H2 2007 Owners Manual

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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Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig.
For example, speed, altitude, road grades, outside
temperature and how much your vehicle is used
to pull a trailer are all important. It can also depend
on any special equipment that you have on your
vehicle, and the amount of tongue weight the
vehicle can carry. See “Weight of the Trailer
Tongue” later in this section for more information.Maximum trailer weight is calculated assuming
only the driver is in the tow vehicle and it has all
the required trailering equipment. The weight
of additional optional equipment, passengers and
cargo in the tow vehicle must be subtracted
from the maximum trailer weight.
Use the following chart to determine how much
your vehicle can weigh, based upon your vehicle
model and options.
Engine Axle Ratio Maximum Trailer Weight **GCWR
6000 V8 (SUV) 4.10 6,700 lbs (3 039 kg) 13,500 lbs (6 123 kg)
6000 V8 (SUT)* 4.10 6,600 lbs (2 994 kg) 13,500 lbs (6 123 kg)
**The Gross Combination Weight Rating (GCWR) in the total allowable weight of the completely loaded vehicle
and trailer including any passengers, cargo, equipment and conversions. The GCWR for your vehicle should not
be exceeded.
*Sport utility truck (SUT) models are neither designed nor intended to tow 5th wheel or gooseneck trailers.
You can ask your dealer for our trailering
information or advice, or you can write us at our
Customer Assistance Offices. SeeCustomer
Assistance Offices on page 540for more
information.
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Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important
weight to measure because it affects the total
gross weight of your vehicle. The Gross Vehicle
Weight (GVW) includes the curb weight of
the vehicle, any cargo you may carry in it, and the
people who will be riding in the vehicle. If you
have a lot of options, equipment, passengers or
cargo in your vehicle, it will reduce the tongue
weight your vehicle can carry, which will also
reduce the trailer weight your vehicle can tow. If
you will tow a trailer, you must add the tongue load
to the GVW because your vehicle will be carrying
that weight, too. SeeLoading Your Vehicle on
page 362for more information about your vehicle’s
maximum load capacity.The trailer tongue weight (A) should be 10 percent
to 15 percent of the total loaded trailer weight (B),
up to a maximum of 500 lbs (227 kg) with a weight
carrying hitch. The trailer tongue weight (A) should
be 10 percent to 15 percent of the total loaded
trailer weight (B), up to a maximum of
700 lbs (318 kg) with a weight distributing hitch.
Do not exceed the maximum allowable tongue
weight for your vehicle. Choose the shortest hitch
extension that will position the hitch ball closest
to the vehicle. This will help reduce the effect
of trailer tongue weight on the rear axle.
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Your spare tire carrier is behind the tailgate.
If your hitch extension is too short, the spare tire
may interfere with trailer coupling or trailer
tongue jack operation on some types of trailers.
After you’ve loaded your trailer, weigh the
trailer and then the tongue, separately, to see if
the weights are proper. If they aren’t, you may be
able to get them right simply by moving some
items around in the trailer.
Trailering may also be limited by the vehicle’s ability
to carry tongue weight. Tongue weight cannot
cause the vehicle to exceed the GVWR (Gross
Vehicle Weight Rating) or the RGAWR (Rear Gross
Axle Weight Rating). The effect of additional weight
may reduce your trailering capacity more than the
total of the additional weight.
Consider the following example:
A vehicle model base weight is 5,500 lbs
(2 495 kg); 2,800 lbs (1 270 kg) at the front
axle and 2,700 lbs (1 225 kg) at the rear axle.It has a GVWR of 7,200 lbs (3 266 kg), a RGAWR
of 4,000 lbs (1 814 kg) and a GCWR (Gross
Combination Weight Rating) of 14,000 lbs
(6 350 kg). The trailer rating should be:
You can expect tongue weight to be at least
10 percent of trailer weight (850 lbs (386 kg)) and
because the weight is applied well behind the rear
axle, the effect on the rear axle will be greater than
just the weight itself, as much as 1.5 times as much.
The weight at the rear axle could be 850 lbs
(386 kg) X 1.5 = 1,275 lbs (578 kg). Since the rear
axle already weighs 2,700 lbs (1 225 kg), adding
1,275 lbs (578 kg) brings the total to 3,975 lbs
(1 803 kg). This is very close to, but within the limit
for RGAWR as well. The vehicle is set to trailer up
to 8,500 lbs (3 856 kg).
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But let’s say your specic vehicle is equipped with
some of the latest options and you have a front seat
passenger and two rear seat passengers with some
luggage and gear in the vehicle as well. You may
add 300 lbs (136 kg) to the front axle weight and
400 lbs (181 kg) to the rear axle weight. Your
vehicle now weighs:
Weight is still below 7,200 lbs (3 266 kg) and you
may think that you should subtract 700 additional
pounds (318 kg) from your trailering capacity
to stay within GCWR limits. Your maximum trailer
would only be 7,800 lbs (3 538 kg). You may go
further and think you must limit tongue weight
to less than 1,000 lbs (454 kg) to avoid exceeding
GVWR. But, you must still consider the effect
on the rear axle. Because your rear axle now
weighs 3,100 lbs (1 406 kg), you can only
put 900 lbs (408 kg) on the rear axle without
exceeding RGAWR. The effect of tongue weight isabout 1.5 times the actual weight. Dividing the
900 lbs (408 kg) by 1.5 leaves you with being able
to handle only 600 lbs (272 kg) of tongue weight.
Since tongue weight is usually at least 10 percent
of total loaded trailer weight, you can expect
that the largest trailer your vehicle can properly
handle is 6,000 lbs (2 721 kg).
It is important that you make sure your vehicle
does not exceed any of its ratings — GCWR,
GVWR, RGAWR, Maximum Trailer Rating
or Tongue Weight. The only way to be sure you
are not exceeding any of these ratings is to weigh
your vehicle and trailer.
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the
upper limit for cold tires. You’ll nd these numbers
on the Certication label at the rear edge of the
driver’s door or seeLoading Your Vehicle on
page 362. Then be sure you don’t go over
the GVW limit for your vehicle, or the GAWR,
including the weight of the trailer tongue. If you use
a weight distributing hitch, make sure you don’t
go over the rear axle limit before you apply
the weight distribution spring bars.
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