2007 CHEVROLET AVALANCHE Owners Manual

The coolant level should be at or above 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.
{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.
Notice:Engine damage from running your
engine without coolant is not covered by your
warranty. SeeOverheated Engine Protection
Operating Mode on page 463for information
on driving to a safe place in an emergency.
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.
465

How to Add Coolant to the Coolant
Surge Tank
If you have not found a problem yet, check to
see if coolant is visible in the surge tank. If coolant
is visible but the coolant level is not at or above
the FULL COLD mark, add a 50/50 mixture
of clean, drinkable water and DEX-COOL
®
coolant at the coolant surge tank, but be sure
the cooling system, including the coolant surge
tank pressure cap, is cool before you do it.
SeeEngine Coolant on page 457for more
information.
If no coolant is visible in the surge tank,
add coolant as follows:
{CAUTION:
Steam and scalding liquids from a hot
cooling system can blow out and burn
you badly. They are under pressure, and if
you turn the coolant surge tank pressure
cap — even a little — they can come out at
high speed. Never turn the cap when the
cooling system, including the coolant
surge tank pressure cap, is hot. Wait for
the cooling system and coolant surge
tank pressure cap to cool if you ever
have to turn the pressure cap.
466

{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 DEX-COOL
®coolant.
Notice:In cold weather, water can freeze and
crack the engine, radiator, heater core and
other parts. Use the recommended coolant
and the proper coolant mixture.
{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.
1. You can remove
the coolant surge
tank pressure
cap when the
cooling system,
including the
coolant surge tank
pressure cap and
upper radiator hose,
is no longer hot.
Turn the pressure cap slowly counterclockwise
about one full turn. If you hear a hiss, wait for
that to stop. A hiss means there is still some
pressure left.
467

2. Then keep turning the pressure cap slowly,
and remove it.
3. Fill the coolant surge tank with the proper
mixture, to the FULL COLD mark.4. With the coolant surge tank pressure cap off,
start the engine and let it run until you can
feel the upper radiator hose getting hot.
Watch out for the engine cooling fan.
By this time, the coolant level inside the
coolant surge tank may be lower. If the level
is lower, add more of the proper mixture
to the coolant surge tank until the level
reaches the FULL COLD mark.
468

5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
6. Verify coolant level after engine is shut off
and the coolant is cold. If necessary, repeat
coolant ll procedure steps 1 through 6.
Engine Fan Noise
Your vehicle has electric cooling fans, you may
hear the fans spinning at low speed during
most everyday driving. The fans may turn off if no
cooling is required. Under heavy vehicle loading,
trailer towing, and/or high outside temperatures,
or if you are operating your air conditioning
system, the fans may change to high speed and
you may hear an increase in fan noise. This
is normal and indicates that the cooling system
is functioning properly. The fans will change to
low speed when additional cooling is no longer
required.
Power Steering Fluid
SeeEngine
Compartment Overview
on page 444for
reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power
steering uid unless you suspect there is a leak
in the system or you hear an unusual noise.
A uid loss in this system could indicate a problem.
Have the system inspected and repaired.
469

How to Check Power Steering Fluid
To check the power steering uid, do the following:
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. Remove the cap again and look at the
uid level on the dipstick.
The level should be at the FULL COLD mark.
If necessary, add only enough uid to bring
the level up to the mark.
What to Use
To determine what kind of uid to use, see
Recommended Fluids and Lubricants on page 574.
Always use the proper uid. Failure to use the
proper uid can cause leaks and damage hoses
and seals.
Windshield Washer Fluid
What to Use
When you need windshield washer uid, be sure
to read the manufacturer’s instructions before
use. If you will be operating your vehicle in an area
where the temperature may fall below freezing,
use a uid that has sufficient protection against
freezing.
470

Adding Washer Fluid
Your vehicle has a low washer uid message
that comes on when the washer uid is low.
The message is displayed for 15 seconds at the
start of each ignition cycle. When the WASHER
FLUID LOW ADD FLUID message is displayed,
you will need to add washer uid to the
windshield washer uid reservoir.
Open the cap with the
washer symbol on it.
Add washer uid
until the tank is full. See
Engine Compartment
Overview on page 444
for reservoir location.Notice:When using concentrated washer uid,
follow the manufacturer’s instructions
for adding water.
Do not mix water with ready-to-use washer
uid. Water can cause the solution to
freeze and damage your washer uid tank
and other parts of the washer system.
Also, water does not clean as well
as washer uid.
Fill your washer uid tank only
three-quarters full when it is very cold.
This allows for expansion if freezing
occurs, which could damage the tank if
it is completely full.
Do not use engine coolant (antifreeze) in
your windshield washer. It can damage
your washer system and paint.
471

Brakes
Brake Fluid
Your brake master
cylinder reservoir is
lled with DOT-3 brake
uid. SeeEngine
Compartment Overview
on page 444for the
location of the reservoir.
There are only two reasons why the brake uid
level in the reservoir might go down. The rst
is that the brake uid goes down to an acceptable
level during normal brake lining wear. When
new linings are put in, the uid level goes back
up. The other reason is that uid is leaking out of
the brake system. If it is, you should have your
brake system xed, since a leak means that
sooner or later your brakes will not work well,
or will not work at all.So, it is not a good idea to top off your brake uid.
Adding brake uid will not correct a leak. If you
add uid when your linings are worn, then you
will have too much uid when you get new brake
linings. You should add or remove brake uid,
as necessary, only when work is done on
the brake hydraulic system.
{CAUTION:
If you have too much brake uid, it can
spill on the engine. The uid will burn
if the engine is hot enough. You or others
could be burned, and your vehicle could
be damaged. Add brake uid only when
work is done on the brake hydraulic
system. See “Checking Brake Fluid”
in this section.
When the brake uid falls to a low level, the brake
warning light will come on. SeeBrake System
Warning Light on page 246.
Refer to the Maintenance Schedule to determine
when to check your brake uid. SeeScheduled
Maintenance on page 563.
472