engine HUMMER H3 2006 Repair Manual

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 4-42.
Dinghy Towing
Use the following procedure to tow your vehicle:
1. Shift the transmission to NEUTRAL (N).
2. Turn the engine off, but leave the ignition in ON.
3. Firmly set the parking brake.
4. Securely attach the vehicle being towed to the
tow vehicle.
{CAUTION:
Shifting an all-wheel-drive vehicle’s transfer
case into NEUTRAL can cause your vehicle to
roll even if the automatic transmission is in
PARK (P) or the manual transmission is in any
gear. 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). See
All-Wheel Drive on page 2-22for the proper
procedure to select the NEUTRAL position for
your vehicle.
6. Put the transmission in PARK (P) for an automatic
transmission or in FIRST (1) for a manual
transmission.
7. Release the parking brake only after the
vehicle being towed is rmly attached to the
towing vehicle.
8. Turn the ignition off.
After towing, see “Shifting Out of NEUTRAL” under
All-Wheel Drive on page 2-22.
4-58

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.
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 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.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
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 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.
4-60

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
Automatic Transmission 4.56 4,500 lbs (2 041 kg) 9,500 lbs (4 309 kg)
Manual Transmission 4.56 3,000 lbs (1 364 kg) 8,000 lbs (3 629 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.
You can ask your dealer for our trailering information
or advice, or you can write us at the address listed
in your Warranty and Owner Assistance Information
Booklet.In Canada, write to:
General Motors of Canada Limited
Customer Communication Centre, 163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
4-61

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 5-27.
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.
4-67

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 or a qualied service center. Also, see
Add-On Electrical Equipment on page 5-95for more
information.
4-68

Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-4
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of
Your Vehicle..............................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-5
California Fuel...............................................5-6
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
Filling the Tank..............................................5-8
Filling a Portable Fuel Container.....................5-10
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-13
Engine Oil Life System..................................5-16
Engine Air Cleaner/Filter................................5-18
Automatic Transmission Fluid.........................5-19
Manual Transmission Fluid.............................5-22
Hydraulic Clutch...........................................5-23
Engine Coolant.............................................5-24
Radiator Pressure Cap..................................5-27
Engine Overheating.......................................5-27Cooling System............................................5-29
Engine Fan Noise.........................................5-33
Power Steering Fluid.....................................5-34
Windshield Washer Fluid................................5-35
Brakes........................................................5-36
Battery........................................................5-39
Jump Starting...............................................5-40
All-Wheel Drive..............................................5-44
Rear Axle.......................................................5-45
Front Axle......................................................5-45
Headlamp Aiming...........................................5-46
Bulb Replacement..........................................5-49
Halogen Bulbs..............................................5-49
Headlamps..................................................5-49
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-50
Replacement Bulbs.......................................5-51
Windshield Wiper Blade Replacement..............5-52
Tires..............................................................5-53
Tire Sidewall Labelling...................................5-54
Tire Terminology and Denitions.....................5-57
Ination - Tire Pressure.................................5-60
Tire Pressure Monitor System.........................5-61
Tire Inspection and Rotation...........................5-64
When It Is Time for New Tires.......................5-65
Section 5 Service and Appearance Care
5-1

Buying New Tires.........................................5-66
Different Size Tires and Wheels......................5-67
Uniform Tire Quality Grading..........................5-68
Wheel Alignment and Tire Balance..................5-69
Wheel Replacement......................................5-69
Tire Chains..................................................5-71
If a Tire Goes Flat........................................5-72
Changing a Flat Tire.....................................5-73
Removing the Spare Tire and Tools................5-75
Removing the Flat Tire and Installing the
Spare Tire................................................5-77
Storing a Flat or Spare Tire and Tools................5-82
Spare Tire...................................................5-84
Appearance Care............................................5-85
Cleaning the Inside of Your Vehicle.................5-85
Fabric/Carpet...............................................5-87
Leather.......................................................5-87
Instrument Panel, Vinyl, and Other
Plastic Surfaces........................................5-88
Care of Safety Belts......................................5-88
Weatherstrips...............................................5-88Washing Your Vehicle...................................5-89
Cleaning Exterior Lamps/Lenses.....................5-89
Finish Care..................................................5-89
Windshield, Backglass, and Wiper Blades.........5-90
Aluminum Wheels.........................................5-91
Tires...........................................................5-91
Sheet Metal Damage.....................................5-92
Finish Damage.............................................5-92
Underbody Maintenance................................5-92
Chemical Paint Spotting.................................5-93
Vehicle Care/Appearance Materials..................5-93
Vehicle Identication......................................5-94
Vehicle Identication Number (VIN).................5-94
Service Parts Identication Label.....................5-95
Electrical System............................................5-95
Add-On Electrical Equipment..........................5-95
Windshield Wiper Fuses................................5-95
Power Windows and Other Power Options.......5-96
Fuses and Circuit Breakers............................5-96
Engine Compartment Fuse Block....................5-97
Capacities and Specications........................5-102
Section 5 Service and Appearance Care
5-2

California Proposition 65 Warning
Most motor vehicles, including this one, contain and/or
emit chemicals known to the State of California to
cause cancer and birth defects or other reproductive
harm. Engine exhaust, many parts and systems
(including some inside the vehicle), many uids, and
some component wear by-products contain and/or emit
these chemicals.
Doing Your Own Service Work
If you want to do some of your own service work,
you will want to use the proper service manual. It tells
you much more about how to service your vehicle
than this manual can. To order the proper service
manual, seeService Publications Ordering Information
on page 7-11.
Your vehicle has an airbag system. Before attempting
to do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 1-64.You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. SeeMaintenance Record on page 6-14.
{CAUTION:
You can be injured and your vehicle could be
damaged if you try to do service work on a
vehicle without knowing enough about it.
Be sure you have sufficient knowledge,
experience, the proper replacement parts,
and tools before you attempt any vehicle
maintenance task.
Be sure to use the proper nuts, bolts,
and other fasteners. English and metric
fasteners can be easily confused. If you
use the wrong fasteners, parts can later
break or fall off. You could be hurt.
5-4

Adding Equipment to the Outside
of Your Vehicle
Things you might add to the outside of your vehicle
can affect the airow around it. This may cause
wind noise and affect windshield washer performance.
Check with your dealer before adding equipment to
the outside of your vehicle.
Fuel
Use of the recommended fuel is an important part of the
proper maintenance of your vehicle.
Gasoline Octane
Use regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less than 87,
you may notice an audible knocking noise when you
drive, commonly referred to as spark knock. If this
occurs, use a gasoline rated at 87 octane or higher as
soon as possible. If you are using gasoline rated at
87 octane or higher and you hear heavy knocking, your
engine needs service.
Gasoline Specications
At a minimum, gasoline should meet ASTM specication
D 4814 in the United States or CAN/CGSB-3.5 in
Canada. Some gasolines may contain an
octane-enhancing additive called methylcyclopentadienyl
manganese tricarbonyl (MMT). General Motors
recommends against the use of gasolines containing
MMT. SeeAdditives on page 5-6for additional
information.
5-5

California Fuel
If your vehicle is certied to meet California Emissions
Standards, it is designed to operate on fuels that
meet California specications. See the underhood
emission control label. If this fuel is not available
in states adopting California emissions standards,
your vehicle will operate satisfactorily on fuels meeting
federal specications, but emission control system
performance may be affected. The malfunction indicator
lamp may turn on and your vehicle may fail a
smog-check test. SeeMalfunction Indicator Lamp on
page 3-35. If this occurs, return to your authorized
GM dealer for diagnosis. If it is determined that
the condition is caused by the type of fuel used,
repairs may not be covered by your warranty.
Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work
properly. In most cases, you should not have to add
anything to your fuel. However, some gasolines contain
only the minimum amount of additive required to
meet U.S. Environmental Protection Agency regulations.
To help keep fuel injectors and intake valves clean,
or if your vehicle experiences problems due to
dirty injectors or valves, look for gasoline that is
advertised as TOP TIER Detergent Gasoline. Also, your
GM dealer has additives that will help correct and
prevent most deposit-related problems.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area. General Motors recommends that you use
these gasolines if they comply with the specications
described earlier. However, E85 (85% ethanol) and other
fuels containing more than 10% ethanol must not be used
in vehicles that were not designed for those fuels.
5-6