2004 GMC YUKON XL DENALI engine

How to Add Coolant to the Coolant
Surge Tank
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 5-23for 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 radiator
pressure cap Ð even a little Ð they can come
out at high speed. Never turn the cap when the
cooling system, including the radiator pressure
cap, is hot. Wait for the cooling system and
radiator 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
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
žcoolant.
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. 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.
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.
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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 FULL COLD mark.
5. 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.
How to Check Power Steering Fluid
Turn the key off, let the engine compartment cool down,
Locate the cap with this
symbol. See
Engine
Compartment Overview on
page 5-12
for more
information on location.
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.
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What to Use
To determine what kind of ¯uid to use, seeRecommended Fluids and Lubricants on page 6-13.
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.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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Notice:
·Using the wrong ¯uid can badly damage brake
system parts. For example, just a few drops of
mineral-based oil, such as engine oil, in your
brake system can damage brake system
parts so badly that they will have to be replaced.
Do not let someone put in the wrong kind of
¯uid.
·If you spill brake ¯uid on your vehicle's painted
surfaces, the paint ®nish can be damaged. Be
careful not to spill brake ¯uid on your vehicle. If
you do, wash it off immediately. See
Appearance
Care on page 5-92.
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 your 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 speci®cations.
Brake linings should always be replaced as complete
axle sets.
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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.
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. Your
vehicle was designed and tested with top-quality GM
brake parts. When you replace parts of your braking
system Ð for example, when your brake linings
wear down and you need new ones put in Ð be sure
you get new approved GM replacement parts. If you do
not, your brakes may no longer work properly. For
example, if someone puts in brake linings that are wrong
for your vehicle, the balance between your front and
rear brakes can change Ð for the worse. The braking
performance you have come to expect can change
in many other ways if someone puts in the wrong
replacement brake parts.
Battery
Your new vehicle comes with a maintenance free
ACDelcožbattery. When it is time for a new battery,
get one that has the replacement number shown on the
original battery's label. We recommend an ACDelco
ž
battery. SeeEngine Compartment Overview on
page 5-12for battery location.Warning: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 Storage
If you are not going to drive your vehicle for 25 days
or more, remove the black, negative (-) cable from
the battery. This will help keep your battery from
running down.
{CAUTION:
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
are not careful. See
Jump Starting on
page 5-40
for tips on working around a battery
without getting hurt.
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