2003 GMC YUKON DENALI Owners Manual

2. Then keep turning the pressure cap slowly, and
remove it.
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3. Then fill the coolant surge tank with the
mixture, to the
FULL COLD mark. proper

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
tu 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 fluid
unless you suspect there is a leak in the system or
you hear an unusual noise. A fluid
loss in this system
could indicate a problem. Have the system inspected
and repaired. See Engine Compartment Overview
on page
5-72 for reservoir location.
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 fluid level on the
dipstick.
The level should be at the
FULL COLD mark. If
necessary, add only enough fluid to bring the level up to
the mark.
What to Use
To determine what kind of fluid to use, see Part D:
Recommended Fluids and Lubricants on page 6-15.
Always use the proper fluid. Failure to use the proper
fluid can cause leaks and damage hoses and seals.
Windshield Washer Fluid
What to Use
When you need windshield washer fluid, 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 fluid that has
sufficient protection against freezing. See Engine
Compartment Overview on page
5-72 for reservoir
location.
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Adding Washer Fluid
Your vehicle has a low washer fluid message that
comes on when the washer fluid
is low. The message is
displayed for
15 seconds at the star? of each ignition
cycle. When the LOW
WASHER FLUID message
is displayed, you will need to add washer fluid to the
windshield washer fluid reservoir.
The windshield washer
the engine compartment
toward the front of the
vehicle on the driver’s side.
4-4- fluid reservoir is located in 111
W
Open the cap with the washer symbol on it. Add washer
fluid until the tank is full.
Notice:
When using concentrated washer fluid, follow
the manufacturer’s instructions for adding water.
Don’t mix water with ready-to-use washer fluid.
Water can cause the solution to freeze and
damage your washer
fluid tank and other parts
of the washer system.
Also, water doesn’t
clean as well as washer fluid.
Fill your washer fluid tank only three-quarters
full when it’s very cold. This allows for expansion if freezing occurs, which could damage the tank if
it is completely full.
Don’t 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 filled with DOT-3
brake fluid. See Engine Compartment Overview on
page
5-12 for the location of the reservoir.
There are only two reasons why the brake fluid level in
the reservoir might go down. The first is that the
brake fluid goes down to an acceptable level during
normal brake lining wear. When new linings are put in,
the fluid level goes back up. The other reason is
that fluid is leaking out of the brake system. If it is, you
should have your brake system fixed, since a leak
means that sooner or later your brakes won’t work well,
or won’t work at all.
So, it isn’t a good idea to “top off’ your brake fluid.
Adding brake fluid won’t correct a leak. If you add fluid
when your linings are worn, then you’ll have
too
much fluid when you get new brake linings. You should
add (or remove) brake fluid, as necessary, only when
work is done on the brake hydraulic system.
If you have too n._.:h brake ------) it can s,
the engine. The fluid will burn if the enginc
... I on
e is
hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
fluid only when work is done
on the brake
hydraulic system. See “Checking Brake Fluid”
in this section.
Refer to the Maintenance Schedule to determine when
to check your brake fluid. See Part C: Periodic
Maintenance Inspections on page
6- 14.
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Checking Brake Fluid
You can check the brake fluid without taking off the cap.
What to Add
When you do need brake fluid, use only DOT-3 brake
fluid. Use new brake fluid from a sealed container only.
see Part D: Recommended Fluids and Lubrjcaats
on page 6- 15.
Just look at the brake fluid reservoir. The fluid level
should be above
MIN. If it isn’t have your brake system
checked to see
if there is a leak.
After work
is done on the brake hydraulic system, make
sure the level is above the
MIN but not over the MAX
mark. Always clean the brake fluid reservoir cap
and the area
around the cap before removing it. This will help
keep dirt from enterinc ++e reservoir.
I
With the wrong kind of fluid in yo^. brake
system, your brakes may not work well, or
they may not even work at all. This could
cause a crash. Always use the proper brake
fluid.
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Notice;
Using the wrong fluid 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’ll have to be replaced.
Don’t let someone put
in the wrong kind of fluid.
If you spill brake fluid on your vehicle’s painted
surfaces,
the paint finish can be damaged. Be
careful not to spill brake fluid on your vehicle. If
you do, wash
it off immediately. See
“Appearance Care’’ in the Index.
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 firmly).
~ The brake wea rarl -g sou.-_. ... eans that
soon your brakes won’t 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 first 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 specifications.
Brake linings should always be replaced as complete
axle sets.
See
Brake System Inspection on page 6-14.
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Brake Pedal Travel Battery
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
- for example, when your brake linings
wear down and you need new ones put in
- be sure
you get new approved
GM replacement parts. If
you don’t, 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
- for the worse. The
braking performance you’ve come to expect can change
in many other ways
if someone puts in the wrong
replacement brake parts. Your
new vehicle comes with a maintenance free
ACDelco@ battery. When it’s time for a new battery, get
one that has the replacement number shown on the
original battery’s label. We recommend an ACDelco@
battery. See Engine Compartment Overview
on
page 5-72 for 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’re not going to drive your vehicle for 25 days or
more, remove the black, negative
(-) cable from
+‘-? battery. This will hc’- keep your battery from
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
aren’t careful. See “Jump Starting” next for
tips on working around a battery without
getting hurt.
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