2004 GMC SIERRA Owner's Manual

How to Add Coolant to the Coolant
Surge Tank for Gasoline Engines
If you haven't found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level isn't at or above the FULL
COLD mark, add a 50/50 mixture of
clean, drinkable
waterand DEX-COOLžcoolant at the coolant
surge tank, but be sure the cooling system, including
the coolant surge tank pressure cap, is cool before you
do it. See
Engine Coolant on page 5-33for 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 Ð even a little Ð 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.
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{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
CAUTION: (Continued)
CAUTION: (Continued)
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 a proper 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.
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1. Park the vehicle on a
level surface. 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.
2. Turn the pressure cap slowly counterclockwise (left)
about one full turn. If you hear a hiss, wait for that to
stop. A hiss means there is still some pressure left.
3. Then keep turning the pressure cap slowly, and
remove it.4. Then ®ll the coolant surge tank with the proper
mixture, to the FULL COLD mark.
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5. 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.6. Then replace the
pressure cap. Be sure
the pressure cap is
hand-tight and
fully seated.
Engine Fan Noise
Your 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 fan is spinning slower and the clutch is not fully
engaged. This improves fuel economy and reduces fan
noise. Under heavy vehicle loading, trailer towing and/or
high outside temperatures, the fan speed increases as
the clutch more fully 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 partially
disengages.
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Power Steering Fluid
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. See
Engine Compartment Overview
on page 5-12for reservoir location. 8100 V8 Engine
All Other Engines
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How to Check Power Steering Fluid
Turn the key off, let the engine compartment cool down,
wipe the cap and the top of the reservoir clean, then
unscrew the cap and wipe the dipstick with a clean rag.
Replace the cap and completely tighten it. Then
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, seeRecommended Fluids and Lubricants on page 6-14.
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. See
Engine
Compartment Overview on page 5-12for reservoir
location.
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 CHECK WASHER FLUID message is
displayed, you will need to add washer ¯uid to the
windshield washer ¯uid reservoir.
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The windshield washer
¯uid reservoir is located in
the engine compartment
toward the front of the
vehicle on the driver's side.
Open the cap with the washer symbol on it. Add washer
¯uid until the tank is full.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.
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Brakes
Brake Fluid
Your brake master cylinder reservoir is ®lled with DOT-3
brake ¯uid. SeeEngine Compartment Overview on
page 5-12for 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 ªtop offº 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 ªChecking Brake Fluidº
in this section.
Refer to the Maintenance Schedule to determine when
to check your brake ¯uid. See
Scheduled Maintenance
on page 6-4.
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