2007 HUMMER H3 engine coolant

Checking Things Under
the Hood
{CAUTION:
An electric fan under the hood can start up
and injure you even when the engine is not
running. Keep hands, clothing, and tools
away from any underhood electric fan.
{CAUTION:
Things that burn can get on hot engine
parts and start a re. These include
liquids like fuel, oil, coolant, brake uid,
windshield washer and other uids, and
plastic or rubber. You or others could be
burned. Be careful not to drop or spill
things that will burn onto a hot engine.
Hood Release
To open the hood, do the following:
1. Pull the handle
with this symbol
on it. It is located
inside the vehicle
on the lower
left side of the
instrument panel.
2. Release the secondary latch on the hood.
It is located below the front center of
the hood.
3. Lift the hood.
Before closing the hood, be sure all the ller caps
are on properly. Then pull the hood down and
close it rmly.
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A. Windshield Washer Fluid Reservoir. See
“Adding Washer Fluid” underWindshield
Washer Fluid on page 346.
B. Engine Coolant Recovery Tank. SeeEngine
Coolant on page 335.
C. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 328.
D. Power Steering Fluid Reservoir. SeePower
Steering Fluid on page 345.
E. Automatic Transmission Fluid Dipstick (If
Equipped). See “Checking the Fluid Level” under
Automatic Transmission Fluid on page 329.
F. Engine Oil Fill Cap. See “When to Add Engine
Oil” underEngine Oil on page 323.
G. Radiator Pressure Cap. SeeCooling System
on page 340.
H. Remote Negative (−) Terminal (GND). See
Jump Starting on page 352.
I. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 323.
J. Positive (+) Battery Terminal. SeeJump
Starting on page 352.
K. Brake Fluid Reservoir. See “Brake Fluid” under
Brakes on page 347.L. Engine Compartment Fuse Block. SeeEngine
Compartment Fuse Block on page 418.
M. Battery. SeeBattery on page 351.
N. Hydraulic Clutch Fluid Reservoir (If Equipped).
SeeHydraulic Clutch on page 334.
Engine Oil
Checking Engine Oil
It is a good idea to check the engine oil every time
you get fuel. In order to get an accurate reading,
the oil must be warm and the vehicle must be
on level ground.
The engine oil dipstick handle is a yellow loop.
SeeEngine Compartment Overview on page 322
for the location of the engine oil dipstick.
1. Turn off the engine and give the oil several
minutes to drain back into the oil pan. If you
do not do this, the oil dipstick might not
show the actual level.
2. Pull out the dipstick and clean it with a paper
towel or cloth, then push it back in all the
way. Remove it again, keeping the tip down,
and check the level.
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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.
335

What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL®coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and the proper coolant.Notice:If you use an improper coolant
mixture, your engine could overheat and be
badly damaged. The repair cost would not be
covered by your warranty. Too much water
in the mixture can freeze and crack the engine,
radiator, heater core, and other parts.
Notice:If you use extra inhibitors and/or
additives in your vehicle’s cooling system,
you could damage your vehicle. Use only the
proper mixture of the engine coolant listed
in this manual for the cooling system.
SeeRecommended Fluids and Lubricants
on page 440for more information.
336

Checking Coolant
The coolant recovery
tank cap has this
symbol on it.
It is located toward the rear of the engine
compartment on the passenger’s side of the
vehicle. SeeEngine Compartment Overview on
page 322for more information on location.
The vehicle must be on a level surface. When
your engine is cold, the coolant level should be
at FULL COLD, or a little higher. When your
engine is warm, the level could be above the
FULL COLD level.
Adding Coolant
If you need more coolant, add the proper
DEX-COOL®coolant mixture at the coolant
recovery tank.
{CAUTION:
Turning the radiator pressure cap when
the engine and radiator are hot can allow
steam and scalding liquids to blow out
and burn you badly. With the coolant
recovery tank, you will almost never
have to add coolant at the radiator. Never
turn the radiator pressure cap — even
a little — when the engine and radiator
are hot.
337

Add coolant mixture at the recovery tank, but be
careful not to spill it.
{CAUTION:
You can be burned if you spill coolant on
hot engine parts. Coolant contains
ethylene glycol, and it will burn if the
engine parts are hot enough. Do not spill
coolant on a hot engine.
Occasionally check the coolant level in the
radiator. For information on how to add coolant to
the radiator, seeCooling System on page 340.
Radiator Pressure Cap
Notice:If the pressure cap is not tightly
installed, coolant loss and possible engine
damage may occur. Be sure the cap is properly
and tightly secured.
SeeEngine Compartment Overview on page 322
for more information on location.
Engine Overheating
A coolant temperature gage is on the instrument
panel. SeeEngine Coolant Temperature Gage
on page 185.
The air conditioning might stop working if the
engine is too hot. This is normal and helps cool
the engine.
If Steam Is Coming From Your Engine
{CAUTION:
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 re.
CAUTION: (Continued)
338

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.
339

Cooling System
When you decide it is safe to lift the hood, here is
what you will see:
A. Coolant Recovery Tank
B. Engine Cooling Fan
C. Radiator Pressure Cap
If the coolant inside the coolant recovery tank is
boiling, do not do anything else until it cools down.
The vehicle should be parked on a level surface.When the engine is cold, the coolant level should
be at least up to the FULL COLD mark. If it is
not, you may have a leak at the pressure cap or in
the radiator hoses, heater hoses, radiator, water
pump or somewhere else in the cooling system.
340