2010 HUMMER H3 tires

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.

10-44 Vehicle Care
Wheels and Tires
Tires
Your new vehicle comes with
high-quality tires made by a
leading tire manufacturer. If you
ever have questions about your
tire warranty and where to
obtain service, see your vehicle
Warranty booklet for details. For
additional information refer to
the tire manufacturer.
{WARNING
Poorly maintained and improperly
used tires are dangerous.
.Overloading your tires can
cause overheating as a result
of too much flexing. You
could have an air-out and a
serious accident. SeeVehicle
Load Limits on page 9‑27.
(Continued)
WARNING (Continued)
.Underinflated tires pose the
same danger as overloaded
tires. The resulting accident
could cause serious injury.
Check all tires frequently to
maintain the recommended
pressure. Tire pressure
should be checked when your
tires are cold. See Tire
Pressure on page 10‑51.
.Overinflated tires are more
likely to be cut, punctured
or broken by a sudden
impact —such as when you
hit a pothole. Keep tires at
the recommended pressure.
.Worn, old tires can cause
accidents. If your tread is
badly worn, or if your tires
have been damaged,
replace them.
Tire Sidewall Labeling
Useful information about a tire
is molded into the sidewall.
The following illustrations are
examples of a typical P‐Metric
and a LT‐Metric tire sidewall.
Passenger (P‐Metric) Tire
(A) Tire Size:The tire size
code is a combination of letters
and numbers used to define a
particular tire's width, height,
aspect ratio, construction type,

Vehicle Care 10-45
and service description. See the
“Tire Size”illustration later in this
section for more detail.
(B) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed to
GM's specific tire performance
criteria have a TPC specification
code molded onto the sidewall.
GM's TPC specifications meet
or exceed all federal safety
guidelines.
(C) DOT (Department of
Transportation)
:The
Department of Transportation
(DOT) code indicates that
the tire is in compliance with
the U.S. Department of
Transportation Motor Vehicle
Safety Standards.
(D) Tire Identification Number
(TIN)
:The letters and numbers
following DOT code are the Tire
Identification Number (TIN). The TIN shows the
manufacturer and plant code,
tire size, and date the tire
was manufactured. The TIN is
molded onto both sides of the
tire, although only one side may
have the date of manufacture.
(E) Tire Ply Material
:The type
of cord and number of plies in
the sidewall and under the tread.
(F) Uniform Tire Quality
Grading (UTQG)
:Tire
manufacturers are required
to grade tires based on
three performance factors:
treadwear, traction, and
temperature resistance.
For more information, see
Uniform Tire Quality Grading
on
page 10‑61
.
(G) Maximum Cold Inflation
Load Limit
:Maximum load
that can be carried and the
maximum pressure needed
to support that load. For information on
recommended tire pressure
see
Tire Pressure
on page 10‑51
and Vehicle Load Limitson
page 9‑27
.
Light Truck (LT-Metric) Tire
(A) Tire Size:The tire size
code is a combination of letters
and numbers used to define a
particular tire's width, height,
aspect ratio, construction type,
and service description. See the
“Tire Size” illustration later in this
section for more detail.