2008 CADILLAC STS engine

3. Fill the coolant surge tank with the proper
DEX-COOL®coolant mixture, to slightly above the
FULL COLD/FROID line on the side of the
coolant surge tank.
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. The upper radiator
hose is the largest of the hoses which comes out of
the radiator, on the passenger side of the vehicle.
Watch out for the engine cooling fans.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/FROID
line on the side of the coolant surge tank.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
Start the engine and allow it to warm up.
How to Add Coolant to the Intercooler
System Fill Neck (4.4L V8 STS-V
Engine Only)
If you have not found a problem yet, turn the engine off
and allow it to cool down, then check to see if coolant
is visible within the horizontal tube section of the
ll neck. If coolant is not visible, add a 50/50 mixture of
clean, drinkable water and DEX-COOL
®coolant to
the ll neck. Be sure the Intercooler System, including
the Intercooler System pressure cap, is cool before
doing so. SeeEngine Coolant on page 5-25for more
information.
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{CAUTION:
Turning the Intercooler System pressure cap
when the engine and intercooler are hot can
allow steam and scalding liquids to blow out
and burn you badly. Never turn the Intercooler
System pressure cap, even a little, when the
engine and intercooler are hot.
{CAUTION:
Adding only plain water to the cooling system
can be dangerous. Plain water, or some other
liquid such as alcohol, can boil before the
proper coolant mixture will. The vehicle’s
coolant warning system is set for the proper
coolant mixture. With plain water or the wrong
mixture, the engine could get too hot but you
would not get the overheat warning. The
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.
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1. Remove the Intercooler System pressure cap when
the Intercooler System, including the upper
intercooler hoses, are no longer hot. Turn the
pressure cap slowly counterclockwise about
one-quarter of a turn. If you hear a hiss, wait for
that to stop. This allows any pressure still left to be
vented.2. Then keep turning the pressure cap slowly, and
remove it.
3. Add the proper DEX-COOL
®coolant mixture to the
ll neck, until the coolant reaches the COLD FILL
line on the ll neck.
4. With the Intercooler System pressure cap off, start
the engine and let it run for a couple of minutes.
Then turn the engine off. By this time, the coolant
level inside the ll neck may be lower. If the
level drops to where coolant is no longer visible in
the horizontal tube section of the ll neck, with
the engine off add more of the DEX-COOL
®coolant
mixture to the ll neck until the level is again
visible in the horizontal tube section.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
If the coolant is not at the proper level when the
system cools down again, see your dealer.
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Power Steering Fluid
SeeEngine Compartment
Overview on page 5-11for
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.
How to Check Power Steering Fluid
To check the power steering uid, do the following:
1. Turn the ignition 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 within the HOT mark. If necessary,
add only enough uid to bring the level within the mark.
What to Use
To determine what kind of uid to use, see
Recommended Fluids and Lubricants on page 6-13.
Always use the proper uid.
Notice:Use of the incorrect uid may damage your
vehicle and the damages may not be covered by
your warranty. Always use the correct uid listed in
Recommended Fluids and Lubricants on page 6-13.
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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.
Adding Washer Fluid
The CHECK WASHER FLUID message will appear on
the Driver Information Center (DIC) when the uid
level is low. SeeDIC Warnings and Messages on
page 3-80for more information.
Open the cap with the
washer symbol on it. Add
washer uid until the
tank is full. SeeEngine
Compartment Overview on
page 5-11for 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 the washer uid tank only three-quarters full
when it is very cold. This allows for uid
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 the vehicle’s
windshield washer system and paint.
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Brakes
Brake Fluid
The brake master cylinder
reservoir is lled with
DOT-3 brake uid. See
Engine Compartment
Overview on page 5-11for
reservoir location and
access.
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 hydraulic system.
If it is, you should have the brake hydraulic system xed,
since a leak means that sooner or later the brakes
will not work well.It is not a good idea to top off the brake uid. Adding
brake uid will not correct a leak. If uid is added when
the linings are worn, there will be too much uid
when new brake linings are installed. Add or remove
brake uid, as necessary, only when work is done on the
brake hydraulic system.
{CAUTION:
If your vehicle has 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.
If the ignition is on and the brake uid is low, the
CHECK BRAKE FLUID message will be displayed in
the Driver Information Center (DIC). SeeDIC Warnings
and Messages on page 3-80.
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What to Add
When you do need brake uid, DOT-3 brake uid is
recommended for use. DOT-4 brake uid is also
compatible with your vehicle’s brake system parts.
However, if you choose to use DOT-4 uid, it is
recommended that you ush the brake hydraulic system
and rell it with new DOT-4 uid at a regular
maintenance service every two years. SeeAdditional
Required Services on page 6-6. Use new brake
uid from a sealed container only. SeeRecommended
Fluids and Lubricants on page 6-13.
Always clean the brake uid reservoir cap and the area
around the cap before removing it. This helps keep
dirt from entering the reservoir.
{CAUTION:
With the wrong kind of uid in the brake
hydraulic system, the brakes might not work
well. This could cause a crash. Always use the
proper brake uid.Notice:
Using the wrong uid can badly damage brake
hydraulic system parts. For example, just a
few drops of mineral-based oil, such as engine
oil, in the brake hydraulic system can damage
brake hydraulic 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. SeeWashing
Your Vehicle on page 5-110.
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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 brake parts.
When you replace parts of the braking system — for
example, when the brake linings wear down and you
need new ones put in — be sure you get new approved
replacement parts. If you do not, the brakes might not
work properly. For example, if someone puts in brake
linings that are wrong for your vehicle, the balance
between the front and rear brakes can change — 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 vehicle has a maintenance free battery. When
it is time for a new battery, see your dealer/retailer
for one that has the replacement number shown on
the original battery’s label. SeeEngine Compartment
Overview on page 5-11for 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
{CAUTION:
Batteries have acid that can burn you and
gas that can explode. You can be badly hurt
if you are not careful. SeeJump Starting on
page 5-45for tips on working around a battery
without getting hurt.
Infrequent Usage: If you drive your vehicle infrequently,
remove the black, negative (−) cable from the battery.
This will help keep the battery from running down.
Extended Storage: For extended storage of your vehicle,
remove the black, negative (−) cable from the battery
or use a battery trickle charger. This will help maintain
the charge of the battery over an extended period
of time.
5-44