2007 HUMMER H2 towing

Following Distance
Stay at least twice as far behind the vehicle ahead
as you would when driving your vehicle without
a trailer. This can help you avoid situations
that require heavy braking and sudden turns.
Passing
You’ll need more passing distance up ahead when
you’re towing a trailer. Because you’re a good
deal longer, you’ll need to go much farther beyond
the passed vehicle before you can return to
your lane.
Backing Up
Hold the bottom of the steering wheel with one
hand. Then, to move the trailer to the left,
just move that hand to the left. To move the trailer
to the right, move your hand to the right. Always
back up slowly and, if possible, have someone
guide you.
Making Turns
Notice:Making very sharp turns while
trailering could cause the trailer to come in
contact with the vehicle. Your vehicle could be
damaged. Avoid making very sharp turns
while trailering.
When you’re turning with a trailer, make wider
turns than normal. Do this so your trailer
won’t strike soft shoulders, curbs, road signs,
trees or other objects. Avoid jerky or sudden
maneuvers. Signal well in advance.
Turn Signals When Towing a Trailer
The arrows on your instrument panel will
ash whenever you signal a turn or lane change.
Properly hooked up, the trailer lamps will also
ash, telling other drivers you’re about to
turn, change lanes or stop.
When towing a trailer, the arrows on your
instrument panel will ash for turns even if the
bulbs on the trailer are burned out. Thus, you may
think drivers behind you are seeing your signal
when they are not. It’s important to check
occasionally to be sure the trailer bulbs are still
working.
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Driving On Grades
Reduce speed and shift to a lower gearbefore
you start down a long or steep downgrade. If you
don’t shift down, you might have to use your
brakes so much that they would get hot and no
longer work well.
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).
You may also want to activate the tow/haul mode
if the transmission shifts too often. See “Tow/Haul
Mode” earlier.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a
lower temperature than at normal altitudes. If you
turn your engine off immediately after towing at high
altitude on steep uphill grades, your vehicle may
show signs similar to engine overheating. To avoid
this, let the engine run while parked (preferably on
level ground) with the automatic transmission in
PARK (P) for a few minutes before turning the
engine off. If you do get the overheat warning,
seeEngine Overheating on page 418.
Parking on Hills
{CAUTION:
You really should not park your
vehicle, with a trailer attached, on a hill.
If something goes wrong, your rig could
start to move. People can be injured, and
both your vehicle and the trailer can be
damaged.
But if you ever have to park your rig on a hill,
here’s how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release
the regular brakes until the chocks absorb
the load.
4. Reapply the regular brakes. Then apply your
parking brake and shift into PARK (P).
5. Release the regular brakes.
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal
down while you:
start your engine,
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the
chocks.
4. Stop and have someone pick up and store
the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when
you’re pulling a trailer. See the Maintenance
Schedule for more on this. Things that are
especially important in trailer operation are
automatic transmission uid (don’t overll),
engine oil, axle lubricant, belts, cooling system
and brake system. Each of these is covered in
this manual, and the Index will help you nd them
quickly. If you’re trailering, it’s a good idea to
review these sections before you start your trip.
Check periodically to see that all hitch nuts
and bolts are tight.
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Trailer Wiring Harness
Heavy-Duty Trailer Wiring Package
Your vehicle is equipped with a trailer towing
harness. This harness with a seven-pin universal
heavy-duty trailer connector is attached to a
bracket on the hitch platform.
The trailer towing harness contains the following
trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Light Blue: Center High-Mounted Stoplamp
(CHMSL)
Red: Battery Feed
Dark Blue: Trailer Brake
A jumper harness for an electric trailer brake
controller and a trailer battery feed fuse may be
included with this trailering package. See
“Instrument Panel Jumper Wiring Harness” later in
this section.
If you need to tow a light-duty trailer with a
standard four-way, round pin connector, an
adapter may be included. See “Four-Wire Harness
Adapter” later in this section.
Instrument Panel Jumper Wiring Harness
Notice:If your vehicle has factory or
dealer-installed HUMMER off-road lamps, the
place where an electric trailer brake connection
must be made is already in use. Do not attempt
to double-up or “piggyback” the connection,
because this could cause a failure or damage to
your vehicle, the electric trailer brake system,
or both. If you want to connect a trailer with
electric brakes to your vehicle, see your dealer
to disconnect the off-road lamps. Also, read
Add-On Electrical Equipment on page 503for
more information.
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Connect the adapter with the tab pointing up.
The ip cap on the vehicle’s seven-wire harness
will lock onto the tab (see arrow in the previous
graphic) and help hold the adapter in place.
Plug the four-way round pin connector onto the
adapter.
Trailer Recommendations
You must subtract your hitch loads from the Cargo
Weight Rating (CWR). CWR is the maximum
weight of the load your vehicle can carry. It doesn’t
include the weight of the people inside, but you
can gure about 150 lbs. (68 kg) for each
seat. The total cargo load must not be more than
your vehicles CWR.
Weigh your vehicle with your trailer attached, so
that you won’t go over the GVWR or GAWR. If you
are using a weight-distributing hitch, weigh the
vehicle without the spring bars in place.
You’ll get the best performance if you spread out
the weight of your load the right way, and if
you choose the correct hitch and trailer brakes.
For more information seeTowing a Trailer
on page 374.
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Notice:If your engine catches re because
you keep driving with no coolant, your vehicle
can be badly damaged. The costly repairs
would not be covered by your warranty.
SeeOverheated Engine Protection Operating
Mode on page 420for information on driving to
a safe place in an emergency.
If No Steam Is Coming From Your
Engine
The ENGINE COOLANT HOT message, along
with a low coolant condition, can indicate a serious
problem.
If you get an engine overheat warning, but see or
hear no steam, the problem may not be too
serious. Sometimes the engine can get a little
too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. SeeTowing a Trailer on
page 374.If you get the ENGINE COOLANT HOT message
with no sign of steam, try this for a minute or so:
1. Turn on your heater to full hot at the highest fan
speed and open the windows as necessary.
2. If you are in a traffic jam, shift to
NEUTRAL (N); otherwise, shift to the highest
gear while driving — DRIVE (D).
If you no longer have the overheat warning,
you can drive. Just to be safe, drive slower for
about 10 minutes. If the warning does not
come back on, you can drive normally.
If the warning continues and you have not
stopped, pull over, stop, and park your vehicle
right away.
If there is still no sign of steam, push down the
accelerator until the engine speed is about
twice as fast as normal idle speed for at least
three minutes while you are parked. If you
still have the warning, turn off the engine and get
everyone out of the vehicle until it cools down.
Also, see “Overheated Engine Protection
Operating Mode” later in this section.
You may decide not to lift the hood but to get
service help right away.
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Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
REDUCED ENGINE POWER message is
displayed, an overheat protection mode which
alternates ring groups of cylinders helps prevent
engine damage. In this mode, you will notice a
loss in power and engine performance. This
operating mode allows your vehicle to be driven to
a safe place in an emergency. Driving extended
miles (km) and/or towing a trailer in the overheat
protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine
damage, allow the engine to cool before
attempting any repair. The engine oil will be
severely degraded. Repair the cause of coolant
loss, change the oil and reset the oil life
system. SeeEngine Oil on page 404.
Cooling System
When you decide it is safe to lift the hood, here is
what you will see:
A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Cooling Fan
If the coolant inside the coolant surge tank is
boiling, do not do anything else until it cools down.
The vehicle should be parked on a level surface.
420

(d)Visually inspect wiper blades for wear or
cracking. Replace wiper blades that appear worn
or damaged or that streak or miss areas of
the windshield.
(e)Make sure the safety belt reminder light and all
your belts, buckles, latch plates, retractors, and
anchorages are working properly. Look for any
other loose or damaged safety belt system parts.
If you see anything that might keep a safety belt
system from doing its job, have it repaired. Have
any torn or frayed safety belts replaced. Also look
for any opened or broken airbag coverings, and
have them repaired or replaced. The airbag system
does not need regular maintenance.
(f)Lubricate all key lock cylinders, hood latch
assembly, secondary latch, pivots, spring anchor,
release pawl, rear compartment hinges, outer
liftgate handle pivot points, rear door detent link,
roller mechanism, liftgate handle pivot points, latch
bolt, fuel door hinge, cargo door hinge, locks,
and folding seat hardware. More frequent
lubrication may be required when exposed to a
corrosive environment. Applying silicone grease on
weatherstrips with a clean cloth will make them
last longer, seal better, and not stick or squeak.Spare tire carrier hinge and latch: Inspect for leaks
and lubricate if required. Remove the setscrew
at the hinge casting and add lubricant, moving the
hinge back and forth periodically, until lubricant
can be seen coming from the setscrew opening.
Install setscrew and tighten to 7 ft lb (9
Y).
SeeRecommended Fluids and Lubricants
on page 528for what lubricant to use.
(g)Check vent hose at transfer case for kinks and
proper installation.
(h)Change automatic transmission uid and lter
if the vehicle is mainly driven under one or
more of these conditions:
In heavy city traffic where the outside
temperature regularly reaches 90°F (32°C)
or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police, or
delivery service.
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