2007 HUMMER H3 service

How to Add Automatic
Transmission Fluid
Refer to the Maintenance Schedule to determine
what kind of transmission uid to use. See
Recommended Fluids and Lubricants on page 440.
Add uid only after checking the transmission
uid while it is hot. A cold check is used only
as a reference. If the uid level is low, add only
enough of the proper uid to bring the level up to
the HOT area for a hot check. It does not take
much uid, generally less than one pint (0.5 L).
Do not overll.
Notice:Use of the incorrect automatic
transmission uid may damage your vehicle,
and the damages may not be covered by
your warranty. Always use the automatic
transmission uid listed inRecommended
Fluids and Lubricants on page 440.
After adding uid, recheck the uid level as
described under “How to Check Automatic
Transmission Fluid,” earlier in this section.
When the correct uid level is obtained, push
the dipstick back in all the way; then ip the
handle down to lock the dipstick in place.
Manual Transmission Fluid
When to Check
A good time to have it checked is when the
engine oil is changed. However, the uid in your
manual transmission does not require changing.
How to Check
Because this operation can be a little difficult,
you may choose to have this done at your
GM dealership service department.
If you do it yourself, be sure to follow all the
instructions here, or you could get a false reading.
Notice:Too much or too little uid can
damage your transmission. Too little uid
could cause the transmission to overheat. Be
sure to get an accurate reading if you check
your transmission uid.
Check the uid level only when your engine is off,
the vehicle is parked on a level place and the
transmission is cool enough for you to rest your
ngers on the transmission case.
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How to Check and Add Fluid
The proper uid should be added if the level does
not reach the bottom of the diaphragm when it
is in place in the reservoir. See the instructions on
the reservoir cap.
Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is
designed to remain in your vehicle for ve years or
150,000 miles (240 000 km), whichever occurs
rst, if you add only DEX-COOL
®extended
life coolant.
The following explains your cooling system and
how to add coolant when it is low. If you have
a problem with engine overheating, seeEngine
Overheating on page 338.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant may require changing sooner, at
the rst maintenance service after each
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would not
be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your
vehicle.
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CAUTION: (Continued)
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 297.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.
If you no longer have the overheat warning, you
can drive. Just to be safe, drive slower for
about 10 minutes. If the warning does not come
back on, you can drive normally.
If the warning continues, pull over, stop, and park
your vehicle right away.
If there is still no sign of steam, idle the engine for
three minutes while you are parked. Push down
the accelerator until the engine speed is about
twice as fast as normal idle speed for at least three
minutes while you are parked. If you still have
the warning, turn off the engine and get everyone
out of the vehicle until it cools down.
You may decide not to lift the hood but to get
service help right away.
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{CAUTION:
Heater and radiator hoses, and other
engine parts, can be very hot. Do not
touch them. If you do, you can be burned.
Do not run the engine if there is a leak. If
you run the engine, it could lose all
coolant. That could cause an engine re,
and you could be burned. Get any leak
xed before you drive the vehicle.
If there seems to be no leak, start the engine
again. The engine cooling fan speed should
increase when idle speed is doubled by pushing
the accelerator pedal down. If it does not,
your vehicle needs service. Turn off the engine.Notice:Engine damage from running your
engine without coolant is not covered by your
warranty.
Notice:Using coolant other than DEX-COOL®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant could require changing sooner, at
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would
not be covered by your warranty. Always
use DEX-COOL
®(silicate-free) coolant in
your vehicle.
341

Brake Wear
Your vehicle has four-wheel 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 may come and go or be heard all
the time your vehicle is moving, except when you
are pushing on the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon the brakes will not work well. That
could lead to an accident. When you hear
the brake wear warning sound, have your
vehicle serviced.
Notice:Continuing to drive with worn-out
brake pads could result in costly brake repair.
Some driving conditions or climates may cause
a brake squeal when the brakes are rst applied or
lightly applied. This does not mean something is
wrong with your 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 GM torque
specications.
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
of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc
brakes adjust for wear.
350

9. Connect the other end of the negative (−) cable
at least 18 inches (45 cm) away from the dead
battery, but not near engine parts that move.
The electrical connection is just as good there,
and the chance of sparks getting back to the
battery is much less.
Your vehicle has a remote negative (−) terminal,
marked GND (Ground), for this purpose.
10. Now start the vehicle with the good battery and
run the engine for a while.
11. Try to start the vehicle that had the dead
battery. If it will not start after a few tries, it
probably needs service.
Notice:If the jumper cables are connected or
removed in the wrong order, electrical shorting
may occur and damage the vehicle. The repairs
would not be covered by your warranty. Always
connect and remove the jumper cables in the
correct order, making sure that the cables do
not touch each other or other metal.A. Heavy, Unpainted Metal Engine Part or
Remote Negative (−) Terminal
B. Good Battery or Remote Positive (+) and
Remote Negative (−) Terminals
C. Dead Battery or Remote Positive (+) Terminal
Jumper Cable Removal
356

The proper level is from 0 to 3/8 inch (0 mm to
10 mm) below the bottom of the ller plug
hole, located on the rear axle.
What to Use
SeeRecommended Fluids and Lubricants on
page 440to determine which kind of lubricant
to use.
Four-Wheel Drive
It is recommended that the four-wheel drive
transfer case uid be checked and lled by
your dealer.
Front Axle
It is not necessary to regularly check front axle
uid unless you suspect there is a leak or you hear
an unusual noise. A uid loss could indicate a
problem.
It is recommended that the front axle uid be
checked and lled by your dealer.
Headlamp Aiming
The vehicle has 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 an accident,
the headlamp aim may be affected and adjustment
may be necessary.
If oncoming vehicles ash 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 in the following
procedure.
358

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 GM Warranty booklet
for details. For additional information refer to
the tire manufacturer’s booklet included with your
vehicle.
{CAUTION:
Poorly maintained and improperly used
tires are dangerous.
Overloading your vehicle’s tires can
cause overheating as a result of too
much friction. You could have an
air-out and a serious accident. See
Loading Your Vehicle on page 289.
CAUTION: (Continued)
CAUTION: (Continued)

Underinated 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 vehicle’s tires are cold. See
Inflation - Tire Pressure on page 375.
Overinated 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 the tire’s tread is badly worn, or
if your vehicle’s tires have been
damaged, replace them.
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