2010 HUMMER H3 Owners Manual

Vehicle Care 10-23
If Steam Is Coming From The
Engine Compartment
{WARNING
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 fire. You or others
could be badly burned. Stop your
engine if it overheats, and get out
of the vehicle until the engine
is cool.
If No Steam Is Coming From
The Engine Compartment
If an engine overheat warning is
displayed but no steam can be seen
or heard, the problem may not be
too serious. Sometimes the engine
can get a little too hot when the
vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
.Tows a trailer. See“Driving on
Grades” underTrailer Towingon
page 9‑74.
If the overheat warning is displayed
with no sign of steam:
1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest
fan speed. Open the windows as
necessary. 3. In heavy traffic, let the engine
idle in N (Neutral) while stopped.
If it is safe to do so, pull off
the road, shift to P (Park) or
N (Neutral) and let the
engine idle.
If the temperature overheat gauge
is no longer in the overheat zone
or an overheat warning no longer
displays, the vehicle can be driven.
Continue to drive the vehicle slow
for about 10 minutes. Keep a safe
vehicle distance from the car in front
of you. If the warning does not come
back on, continue to drive normally.
If the warning continues, pull
over, stop, and park the vehicle
right away.
If there is no sign of steam, idle
the engine for three minutes while
parked. If the warning is still
displayed, turn off the engine until
it cools down.

10-24 Vehicle Care
Engine Fan
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 Overviewon page 10‑6for reservoir location.
When to Check Power Steering
Fluid
It is not necessary to regularly
check power steering fluid unless a
leak in the system is suspected or
an unusual noise is heard. A fluid
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.
4. Replace the cap and completely tighten it.
5. Then remove the cap again and look at the fluid level on the
dipstick.
The level should be between the
ADD and FULL marks. If necessary,
add only enough fluid to bring the
level up to the proper range.

Vehicle Care 10-25
What to Use
To determine what kind of fluid to
use, seeRecommended Fluids and
Lubricants
on page 11‑8. Always
use the proper fluid.
Notice: Use of the incorrect fluid
may damage the vehicle and the
damages may not be covered by
the vehicle's warranty. Always
use the correct fluid listed in
Recommended Fluids and
Lubricants on page 11‑8.
Washer Fluid
What to Use
When windshield washer fluid
is needed, be sure to read the
manufacturer's instructions before
use. If operating the vehicle in an
area where the temperature may fall
below freezing, use a fluid that has
sufficient protection against
freezing.
Adding Washer Fluid
Open the cap with the washer
symbol on it. Add washer fluid
until the tank is full. See Engine
Compartment Overview
on
page 10‑6for reservoir location.
Notice:
.When using concentrated
washer fluid, follow the
manufacturer's instructions
for adding water.
.Do not mix water with
ready-to-use washer fluid.
Water can cause the solution
to freeze and damage the
washer fluid tank and other
parts of the washer system.
Also, water does not clean as
well as washer fluid.
.Fill the washer fluid tank
only three-quarters full
when it is very cold. This
allows for fluid expansion if
freezing occurs, which could
damage the tank if it is
completely full.
.Do not use engine coolant
(antifreeze) in the windshield
washer. It can damage the
vehicle's windshield washer
system and paint.

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 10-27
Brake Fluid
The brake master cylinder reservoir
is filled with DOT 3 brake fluid as
indicated on the reservoir cap. See
Engine Compartment Overview
on
page 10‑6for the location of the
reservoir. There are only two reasons why the
brake fluid level in the reservoir
might go down:
.The brake fluid level goes down
because of normal brake lining
wear. When new linings are
installed, the fluid level goes
back up.
.A fluid leak in the brake
hydraulic system can also cause
a low fluid level. Have the brake
hydraulic system fixed, since a
leak means that sooner or later
the brakes will not work well.
Do not top off the brake fluid.
Adding fluid does not correct a leak.
If fluid is added when the linings
are worn, there will be too much
fluid when new brake linings are
installed. Add or remove brake fluid,
as necessary, only when work is
done on the brake hydraulic system.
{WARNING
If too much brake fluid is added, it
can spill on the engine and burn,
if the engine is hot enough. You
or others could be burned, and
the vehicle could be damaged.
Add brake fluid only when work is
done on the brake hydraulic
system.
When the brake fluid falls to a low
level, the brake warning light comes
on. See Brake System Warning
Light on page 5‑14.

10-28 Vehicle Care
What to Add
Use only new DOT 3 brake fluid
from a sealed container. See
Recommended Fluids and
Lubricants on page 11‑8.
Always clean the brake fluid
reservoir cap and the area around
the cap before removing it. This
helps keep dirt from entering the
reservoir.
{WARNING
With the wrong kind of fluid in
the brake hydraulic system, the
brakes might not work well. This
could cause a crash. Always use
the proper brake fluid.Notice:
.Using the wrong fluid
can badly damage brake
hydraulic system parts. For
example, just a few drops of
mineral-based oil, such as
engine oil, in the brake
hydraulic system can
damage brake hydraulic
system parts so badly that
they will have to be replaced.
Do not let someone put in
the wrong kind of fluid.
.If brake fluid is spilled
on the vehicle's painted
surfaces, the paint finish can
be damaged. Be careful not
to spill brake fluid on the
vehicle. If you do, wash it off
immediately.
Battery
Refer to the replacement number
shown on the original battery label
when a new battery is needed. See
Engine Compartment Overview
on
page 10‑6for battery location.
{DANGER
Battery posts, terminals, and
related accessories contain lead
and lead compounds, chemicals
known to the State of California to
cause cancer and reproductive
harm. Wash hands after handling.

Vehicle Care 10-29
Vehicle Storage
{WARNING
Batteries have acid that can burn
you and gas that can explode.
You can be badly hurt if you are
not careful. SeeJump Starting
on
page 10‑86
for tips on working
around a battery without
getting hurt.
Infrequent Usage: Remove the
black, negative (−) cable from the
battery to keep the battery from
running down.
Extended Storage: Remove the
black, negative (−) cable from the
battery or use a battery trickle
charger.
Four-Wheel Drive
It is recommended that the
four-wheel drive transfer case fluid
be checked and filled by the dealer.
Front Axle
It is not necessary to regularly
check front axle fluid unless a leak
is suspected or an unusual noise is
heard. A fluid loss could indicate a
problem.
It is recommended that the front
axle fluid be checked and filled by
your dealer.
Rear Axle
When to Check and Change
Lubricant
It is not necessary to regularly
check rear axle fluid unless a leak is
suspected or an unusual noise is
heard. A fluid loss could indicate a
problem. Have it inspected and
repaired.
How to Check Lubricant
To get an accurate reading, the
vehicle should be on a level
surface.
A. Rear Axle
B. Filler Plug
The proper level for the rear
axle fluid is 0 mm to 10 mm
(0 to 3/8 inch) below the bottom of
the filler plug hole, located on the
rear axle.
What to Use
See Recommended Fluids and
Lubricantson page 11‑8to
determine which kind of lubricant
to use.

10-30 Vehicle Care
Starter Switch Check
{WARNING
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular brake.
See Parking Brake
on
page 9‑51.
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts. 3. For automatic transmission
vehicles, try to start the engine
in each gear. The vehicle
should start only in P (Park) or
N (Neutral). If the vehicle starts
in any other position, contact
your dealer for service.
For manual transmission
vehicles, put the shift lever in
Neutral, push the clutch pedal
down halfway, and try to start
the engine. The vehicle should
start only when the clutch pedal
is pushed down all the way to
the floor. If the vehicle starts
when the clutch pedal is not
pushed all the way down,
contact your dealer for service.
Automatic Transmission
Shift Lock Control
System Check
{WARNING
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface.
2. Firmly apply the parking brake. See Parking Brake
on
page 9‑51.
Be ready to apply the regular
brake immediately if the vehicle
begins to move.