tires HUMMER H3 2010 Owner's Manual

9-44 Driving and Operating
2 (Second):This position reduces
vehicle speed even more than
3 (Third) without using the brakes.
You can use 2 (Second) on hills.
It can help control vehicle speed as
you go down steep mountain roads,
but then you would also want to use
the brakes off and on.
1 (First): This position reduces
vehicle speed even more than
2 (Second) without using the brakes.
You can use it on very steep hills,
or in deep snow or mud. If the shift
lever is put in 1 (First) while the
vehicle is moving forward, the
transmission will not shift into
first gear until the vehicle is going
slowly enough. Notice:
Spinning the tires
or holding the vehicle in
one place on a hill using only
the accelerator pedal may
damage the transmission.
The repair will not be covered by
the vehicle warranty. If you are
stuck, do not spin the tires. When
stopping on a hill, use the brakes
to hold the vehicle in place.
Hill Start Assist
H3 and H3T vehicles have a Hill
Start Assist feature, which may be
useful when stopped on a grade.
See Braking
on page 9‑3for more
information.
Manual Transmission
This is the shift pattern.
Vehicles with a manual transmission
operate as described below:
1 (First): Press the clutch pedal
and shift into 1 (First). Then slowly
let up on the clutch pedal as
you slowly press down on the
accelerator pedal.

9-46 Driving and Operating
Shift Speeds
{WARNING
If you skip a gear when you
downshift, you could lose control
of the vehicle. You could injure
yourself or others. Do not shift
down more than one gear at a
time when you downshift.
Hill Start Assist
H3 and H3T vehicles have a Hill
Start Assist feature, which may be
useful when stopped on a grade.
SeeBraking
on page 9‑3for more
information.
Drive Systems
Four-Wheel Drive
Full-Time Four-Wheel Drive sends
engine power to all four wheels for
extra traction. To get the most out of
Full-Time Four-Wheel Drive, you
must be familiar with its operation.
Transfer Case Buttons
The transfer case buttons are
located to the right of the instrument
panel cluster. Use these switches
to shift into and out of the different
Full-Time Four-Wheel Drive modes. 4
m(Four-Wheel High):
This
setting is used for driving in most
street and highway situations. You
can also use this setting for light or
variable off-road conditions.
N (Neutral): Shift the transfer case
to Neutral only when towing the
vehicle. See Driving Characteristics
and Towing Tips
on page 9‑70for
more information.
Notice: Driving on pavement
in Four-Wheel High Lock or
Four Wheel Low Lock for
extended periods may cause
premature wear on the vehicle
powertrain and tires. Do not
drive in Four-Wheel High Lock
or Four-Wheel Low Lock on
pavement for extended periods.
4
m Q(Four-Wheel-High Lock):
Use this setting when you need
extra traction in most off-road
situations such as sand, mud,
snow or level, rocky trails.

Driving and Operating 9-55
To lock the rear axle, do the
following:
1. Place the transfer case in the4LO Lock mode. This is the
only mode which will allow
the rear axle to lock. See
Four-Wheel Drive
on page 9‑46for more information regarding
the transfer case and
4LO Lock mode.
2. Press the rear axle locking button with the vehicle moving
less than 26 km/h (16 mph).
The light in the button stops flashing
and remains illuminated when the
rear axle is locked.
Notice: If you try to lock the axle
while the vehicle is stuck and the
tires are spinning, the vehicle's
drivetrain could be damaged. The repairs would not be covered
by the vehicle warranty. Always
lock the axle before attempting
situations and/or navigating
terrain which could possibly
cause the vehicle to become
stuck.
The locking rear axle will be
disengaged when the wheel speed
is greater than 64 km/h (40 mph),
if the vehicle's battery is low and/or
the transfer case is shifted out of
4LO Lock mode.
Notice:
If the vehicle's axle
is locked while driving on
pavement, the drivetrain could be
damaged. Repairs would not be
covered by the vehicle warranty.
Do not use the locking axle on
pavement. If four-wheel drive is
needed when traveling on
pavement, use only 4HI.
Locking Front Axle
For vehicles with this feature, the
locking front axle, used with the
locking rear axle, can give the
vehicle additional traction when
traveling in off-road situations such
as mud, snow, sand, steep hills and
uneven terrain.
The button used to turn the locking
front axle on or off is located on the
instrument panel.
Before the front axle can be locked,
the rear axle must be locked.

9-56 Driving and Operating
To lock the front and rear axles:
1. Place the transfer case in the4LO Lock mode. This is the
only mode which allows the
front and rear axles to lock.
See Four-Wheel Drive
on
page 9‑46for more information
regarding the transfer case and
4LO Lock mode.
2. Press the rear axle locking button with the vehicle moving
less than 16 mph (26 km/h).
3. Wait for the light in the button to stop flashing and remain
illuminated to show that the rear
axle is locked.
4. Press the front axle locking button with the vehicle stopped
or moving less than 26 km/h
(16 mph). 5. Wait for the light in the button
to stop flashing and remain
illuminated to show that the front
axle is locked.
Notice: If you try to lock the axle
while the vehicle is stuck and the
tires are spinning, the vehicle's
drivetrain could be damaged.
The repairs would not be covered
by the vehicle warranty. Always
lock the axle before attempting
situations and/or navigating
terrain which could possibly
cause the vehicle to become
stuck. Locking axles will be disengaged
when the wheel speed is greater
than 64 km/h (40 mph), if the
vehicle's battery is low and/or the
transfer case is shifted out of
4LO Lock mode.
Notice:
If the vehicle's axle
is locked while driving on
pavement, the drivetrain could be
damaged. Repairs would not be
covered by the vehicle warranty.
Do not use the locking axle on
pavement. If four-wheel drive is
needed when traveling on
pavement, use only 4HI.

Driving and Operating 9-71
With the added weight, the engine,
transmission, wheel assemblies and
tires are forced to work harder and
under greater loads. The trailer also
adds wind resistance, increasing
the pulling requirements. For safe
trailering, correctly use the proper
trailering equipment.
The following information has
important trailering tips and rules
for your safety and that of your
passengers. Read this section
carefully before pulling a trailer.
Pulling A Trailer
Here are some important points:
.There are many laws, including
speed limit restrictions that apply
to trailering. Check for legal
requirements with state or
provincial police.
.Consider using a sway control.
See“Hitches” later in this
section.
.Do not tow a trailer at all during
the first 800 km (500 miles) the
new vehicle is driven. The
engine, axle or other parts could
be damaged.
.Then, during the first 800 km
(500 miles) that a trailer is
towed, do not drive over 80 km/h
(50 mph) and do not make starts
at full throttle. This helps the
engine and other parts of the
vehicle wear in at the heavier
loads.
.Vehicles with an automatic
transmission can tow in
D (Drive). Use a lower gear if
the transmission shifts too often.
For vehicles with a manual
transmission, it is better not to
use the highest gear.
.This vehicle has a Hill Start
Assist feature, which may be
useful when the vehicle is
stopped on a grade. See Hill
Start Assist (HSA)
on page 9‑52for more information.
.Do not drive faster than the
maximum posted speed for
trailers.
Driving with a Trailer
Towing a trailer requires experience.
Get familiar with handling and
braking with the added trailer
weight. The vehicle is now longer
and not as responsive as the
vehicle is by itself.
Check all trailer hitch parts and
attachments, safety chains,
electrical connectors, lamps, tires
and mirror adjustments. If the trailer
has electric brakes, start the vehicle
and trailer moving and then apply
the trailer brake controller by hand
to be sure the brakes are working.
During the trip, check occasionally
to be sure that the load is secure,
and the lamps and trailer brakes are
working properly.

9-74 Driving and Operating
Leaving After Parking on a Hill
1. Apply and hold the brake pedalwhile you:
.start the 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
The vehicle needs service more
often when pulling a trailer. See this
manual's Maintenance Schedule
or Index for more information.
Things that are especially important
in trailer operation are automatic
transmission fluid, engine oil, axle lubricant, belts, cooling system and
brake system. It is a good idea to
inspect these before and during
the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See
Engine Overheating
on page 10‑22.
Trailer Towing
Three important considerations
have to do with weight:
.The weight of the trailer.
.The weight of the trailer tongue.
.The total weight on the vehicle's
tires.
Weight of the Trailer
How heavy can a trailer safely be?
Speed, altitude, road grades,
outside temperature, special
equipment, and the amount of
tongue weight the vehicle can carry
must be considered. 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 a vehicle can weigh,
based on the vehicle model and
options.

9-78 Driving and Operating
Total Weight on the Vehicle's
Tires
Inflate the vehicle's tires to the
upper limit for cold tires. These
numbers can be found on the
Certification label or seeVehicle
Load Limits
on page 9‑27. Do
not go over the GVW limit for the
vehicle, or the GAWR, including the
weight of the trailer tongue.
Towing Equipment
Hitches
It is important to have the correct
hitch equipment. Crosswinds, large
trucks going by and rough roads are
a few reasons why the right hitch is
needed. The rear bumper on the vehicle is
not intended for hitches. Do not
attach rental hitches or other
bumper-type hitches to it. Use only
a frame-mounted hitch that does not
attach to the bumper.
Will any holes be made in the body
of the vehicle when the trailer hitch
is installed? If there are, then be
sure to seal the holes when the
hitch is removed. If the holes are not
sealed, dirt, water, and deadly
carbon monoxide (CO) from the
exhaust may get into the vehicle.
See
Engine Exhaust on page 9‑40. Weight-Distributing Hitches and
Weight Carrying Hitches(A) Body-to-Ground Distance (B)
Front of Vehicle
When using a weight-distributing
hitch, the hitch must be adjusted so
that the distance (A) remains the
same both before and after coupling
the trailer to the tow vehicle.

10-2 Vehicle Care
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . 10-44
Tire Sidewall Labeling . . . . . . 10-44
Tire Designations . . . . . . . . . . . 10-46
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . 10-48
Tire Pressure . . . . . . . . . . . . . . . 10-51
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . 10-52
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . 10-53
Tire Inspection . . . . . . . . . . . . . . 10-57
Tire Rotation . . . . . . . . . . . . . . . 10-57
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . 10-58
Buying New Tires . . . . . . . . . . . 10-59
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . 10-60
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . 10-61 Wheel Alignment and Tire
Balance . . . . . . . . . . . . . . . . . . . 10-62
Wheel Replacement . . . . . . . . 10-63
Tire Chains . . . . . . . . . . . . . . . . . 10-64
If a Tire Goes Flat . . . . . . . . . . 10-64
Tire Changing (H3T) . . . . . . . . 10-66
Tire Changing (H3) . . . . . . . . . 10-75
Secondary Latch System . . . 10-84
Full-Size Spare Tire . . . . . . . . 10-85
Jump Starting
Jump Starting . . . . . . . . . . . . . . 10-86
Towing
Towing the Vehicle . . . . . . . . . 10-90
Recreational Vehicle Towing . . . . . . . . . . . . . . . . . . . . 10-90
Appearance Care
Exterior Care . . . . . . . . . . . . . . . 10-92
Interior Care . . . . . . . . . . . . . . . . 10-96
General Information
For service and parts needs, visit
your dealer/retailer. You will receive
genuine parts and trained and
supported service people.
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,
many fluids, and some component
wear by-products contain and/or
emit these chemicals.

10-26 Vehicle Care
Brakes
This vehicle has disc brakes. Disc
brake pads have built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn and new pads are needed.
The sound can come and go or be
heard all the time the vehicle is
moving, except when applying the
brake pedal firmly.
{WARNING
The brake wear warning sound
means that soon the brakes will
not work well. That could lead to
an accident. When the brake
wear warning sound is heard,
have the vehicle serviced.
Notice: Continuing to drive with
worn-out brake pads could result
in costly brake repair. Some driving conditions or climates
can cause a brake squeal when the
brakes are first applied or lightly
applied. This does not mean
something is wrong with the brakes.
Properly torqued wheel nuts are
necessary to help prevent brake
pulsation. When tires are rotated,
inspect brake pads for wear and
evenly tighten wheel nuts in the
proper sequence to torque
specifications in
Capacities and
Specifications on page 12‑2.
Brake linings should always be
replaced as complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal
does not return to normal height,
or if there is a rapid increase in
pedal travel. This could be a sign
that brake service might be
required.
Brake Adjustment
Every time the brakes are applied,
with or without the vehicle moving,
the brakes adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is
complex. Its many parts have to be
of top quality and work well together
if the vehicle is to have really good
braking. The vehicle was designed
and tested with top-quality brake
parts. When parts of the braking
system are replaced, be sure to get
new, approved replacement parts.
If this is not done, the brakes might
not work properly. For example,
installing disc brake pads that are
wrong for the vehicle, can change
the balance between the front and
rear brakes —for the worse. The
braking performance expected can
change in many other ways if the
wrong replacement brake parts are
installed.

Vehicle Care 10-33
Headlamp Aiming
The vehicle may have a visual
optical headlamp aiming system.
The aim has been preset at the
factory and should need no further
adjustment.
However, if the vehicle is damaged
in a crash, the headlamp aim may
be affected and adjustment may be
necessary.
If oncoming vehicles flash their high
beams at you, this may also mean
the vertical aim needs to be
adjusted.
It is recommended that the vehicle
is taken to your dealer for service if
the headlamps need to be re-aimed.
It is possible however, to re-aim the
headlamps as described.The vehicle should be:.Placed so the headlamps are
7.6 m (25 ft) from a light colored
wall or other flat surface.
.On a level surface which is level
all the way to a wall.
.Placed so it is at a right angle to
the wall or other flat surface.
.Clear of any snow, ice, or mud
on it.
.Fully assembled, the tires
properly inflated, and all other
work stopped while headlamp
aiming is being performed.
.Normally loaded with the spare
tire in its original location and a
full tank of fuel and one person
or 75 kg (160 lbs) sitting on the
driver seat.To adjust the vertical aim:
1. Open the hood. See
Hood
on
page 10‑5.
2. Record the distance from the ground to the aim dot on the
headlamp.