Towing HUMMER H3 2008 Owner's Manual

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.
4-57

Driving On Grades
Reduce speed and shift to a lower gearbeforeyou 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.
If you have an automatic transmission, 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 under heavy loads
and/or hilly conditions.
If you have a manual transmission and you are towing a
trailer, it is better not to use the highest gear.
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. For manual transmissions,
let the engine run while parked, preferably on level
ground, with the transmission out of gear and the parking
brake applied, for a few minutes before turning the engine
off. If you do get the overheat warning, seeEngine
Overheating on page 5-29.
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 for an automatic transmission, or into
gear for a manual transmission. Turn your wheels
into the curb if facing downhill or into traffic if facing
uphill.
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) for an
automatic transmission or into gear for a manual
transmission.
5. Release the regular brakes.
4-58

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, 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.
Trailer Wiring Harness
Light-Duty Trailer Wiring Package
If your vehicle is not equipped with a trailer towing
package, the chassis harness will contain the following
blunt cut circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
White: Ground
Brown: Tail Lamps
If you want to add on a trailer tow, it should be installed
by your dealer/retailer or a qualied service center.
Also, seeAdd-On Electrical Equipment on page 5-101
for more information.
4-59

Heavy-Duty Trailer Wiring Package
If your vehicle is equipped with a trailer towing package,
the rear bumper harness will have a seven-pin universal
heavy-duty trailer connector attached to a bracket on the
hitch platform.The trailer towing harness contains the following seven
trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Red: Battery Feed
Dark Blue: Trailer Brake
If you are charging a remote (non-vehicle) battery, turn
on the headlamps to boost the vehicle system voltage
to properly charge the battery.
4-60

Trailer Brake Control Wiring Harness
The trailer brake control wiring harness is located
under the instrument panel to the right of the steering
column. The wires are taped to the harness that goes
to the courtesy light under the instrument panel.
The harness will contain the following wires:
Red Wire: AUX B+
Black Wire: Ground
Light Blue Wire: Brake Signal
Dark Blue Wire: Trailer Brakes
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 4-50.
4-62

If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can burn
you badly, even if you just open the hood. Stay
away from the engine if you see or hear steam
coming from it. Just turn it off and get
everyone away from the vehicle until it cools
down. Wait until there is no sign of steam or
coolant before you open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch re. You
or others could be badly burned. Stop your
engine if it overheats, and get out of the
vehicle until the engine is cool.
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.
If No Steam Is Coming From Your
Engine
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. See “Driving on Grades” under
Towing a Trailer on page 4-50.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL
while stopped. If it is safe to do so, pull off the
road, shift to PARK (P) or NEUTRAL and let the
engine idle.
2. Turn off the air conditioning.
3. Turn on your heater to full hot at the highest fan
speed and open the windows as necessary.
5-30

Engine Fan Noise
This vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the clutch is not engaged. This improves fuel
economy and reduces fan noise. Under heavy vehicle
loading, trailer towing and/or high outside temperatures,
the fan speed increases when the clutch engages.
So you may hear an increase in fan noise. This
is normal and should not be mistaken as the
transmission slipping or making extra shifts. It is merely
the cooling system functioning properly. The fan will
slow down when additional cooling is not required and
the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
Power Steering Fluid
SeeEngine Compartment
Overview on page 5-12for
reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power steering uid
unless you suspect there is a leak in the system or
you hear an unusual noise. A uid loss in this system
could indicate a problem. Have the system inspected
and repaired.
How to Check Power Steering Fluid
1. Turn the key off and let the engine compartment
cool down.
2. Wipe the cap and the top of the reservoir clean.
3. Unscrew the cap and wipe the dipstick with a
clean rag.
5-36

(d)Inspect wiper blades for wear, cracking, or
contamination. Clean the windshield and wiper blades, if
contaminated. Replace wiper blades that are worn or
damaged. See Windshield Wiper Blade Replacement on
page 5-52 and Windshield, Backglass, and Wiper
Blades on page 5-97 for more information.
(e)Make sure the safety belt reminder light and safety
belt assemblies 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 see Checking
the Restraint Systems on page 1-69.
(f)Lubricate all key lock cylinders, hood latch assembly,
secondary latch, pivots, spring anchor, release pawl,
rear compartment hinges, outer swing-gate handle pivot
points, rear door detent link, roller mechanism,
swing-gate handle pivot points, latch bolt, fuel 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.(g)Check vent hose at transfer case for kinks and
proper installation.
(h)Change automatic transmission fluid and filter 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.
(i)Drain, flush, and refill cooling system. This service
can be complex; you should have your dealer/retailer
perform this service. See Engine Coolant on page 5-27
for what to use. Inspect hoses. Clean radiator,
condenser, pressure cap, and filler neck. Pressure test
the cooling system and pressure cap.
(j)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the fluid level checked. Add fluid if needed.
(k)Visually inspect belt for fraying, excessive cracks, or
obvious damage. Replace belt if necessary.
6-8

HUMMER Technician Roadside Service
(U.S. only)
HUMMER’s exceptional Roadside Service is more
than an auto club or towing service. It provides every
HUMMER owner in the United States with the
advantage of contacting a HUMMER advisor and, where
available, a HUMMER trained dealer technician who
can provide on-site service.
A dealer technician will travel to your location generally
within a 30 mile radius of a participating HUMMER
dealership. If beyond this radius, we will arrange to have
your car towed to the nearest HUMMER dealership.
Each technician travels with a specially equipped service
vehicle complete with the necessary HUMMER parts
and tools required to handle most roadside repairs.
Calling for Assistance
For prompt and efficient assistance when calling, please
provide the following to the Roadside Assistance
Representative:
Your name, home address, and home telephone
number
Telephone number of your location
Location of the vehicle
Model, year, color, and license plate number of the
vehicle
Odometer reading, Vehicle Identication
Number (VIN), and delivery date of the vehicle
Description of the problem
Towing and Road Service Exclusions
Specically excluded from Roadside Service coverage
are towing or services for vehicles operated on a
non-public roadway or highway, nes, impound towing
caused by a violation of local, Municipal, State,
Provincial or Federal law, and mounting, dismounting or
changing of snow tires, chains, or other traction
devices.
Roadside Assistance is not part of or included in the
coverage provided by the New Vehicle Limited Warranty.
HUMMER and General Motors of Canada Limited
reserve the right to make any changes or discontinue
the Roadside Assistance program at any time without
notication.
7-8

Insuring Your Vehicle
Protect your investment in your GM vehicle with
comprehensive and collision insurance coverage. There
are signicant differences in the quality of coverage
afforded by various insurance policy terms. Many
insurance policies provide reduced protection to your
GM vehicle by limiting compensation for damage repairs
by using aftermarket collision parts. Some insurance
companies will not specify aftermarket collision
parts. When purchasing insurance, we recommend that
you assure your vehicle will be repaired with GM
original equipment collision parts. If such insurance
coverage is not available from your current insurance
carrier, consider switching to another insurance carrier.
If your vehicle is leased, the leasing company may
require you to have insurance that assures repairs with
Genuine GM Original Equipment Manufacturer (OEM)
parts or Genuine Manufacturer replacement parts. Read
your lease carefully, as you may be charged at the
end of your lease for poor quality repairs.
If a Crash Occurs
Here is what to do if you are involved in a crash.
Try to relax and then check to make sure you are
all right. If you are uninjured, make sure that no
one else in your vehicle, or the other vehicle,
is injured.
If there has been an injury, call emergency services
for help. Do not leave the scene of a crash until all
matters have been taken care of. Move your
vehicle only if its position puts you in danger or you
are instructed to move it by a police officer.
Give only the necessary and requested information
to police and other parties involved in the crash.
Do not discuss your personal condition, mental
frame of mind, or anything unrelated to the crash.
This will help guard against post-crash legal action.
If you need roadside assistance, call GM Roadside
Assistance. SeeRoadside Assistance Program on
page 7-6for more information.
If your vehicle cannot be driven, know where the
towing service will be taking it. Get a card from
the tow truck operator or write down the driver’s
name, the service’s name, and the phone number.
7-12