2006 CADILLAC STS engine

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 the FULL COLD/FROID
line on the side of the coolant surge tank, 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 5-26for more information.
{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.
{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.
5-34

{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.
If no coolant is visible in the surge tank, add coolant
as follows:
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-quarter of a turn. If
you hear a hiss, wait for that to stop. A hiss means
there is still some pressure left.2. Then keep turning the pressure cap slowly, and
remove it.
5-35

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’s 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. If the CHECK
COOLANT LEVEL message does not appear on the
Driver Information Center (DIC), the coolant is at
the proper ll level. If the CHECK COOLANT LEVEL
message does appear, repeat Steps 1 to 3 then reinstall
the pressure cap, or see your GM dealer.
5-36

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. See
Engine Coolant on page 5-26for more information.
{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 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.
5-37

{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 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 will allow 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.
5-38

Power Steering Fluid
SeeEngine Compartment
Overview on page 5-12for
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 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 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 6-12.
Always use the proper uid. Failure to use the proper
uid can cause leaks and damage hoses and seals.
5-39

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 3-79for more information.
Open the cap with the
washer symbol on it. Add
washer uid until the
tank is full. SeeEngine
Compartment Overview on
page 5-12for 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.
5-40

Brakes
Brake Fluid
Your brake master cylinder
reservoir is lled with
DOT-3 brake uid. See
Engine Compartment
Overview on page 5-12
for 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 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.
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 3-79.
5-41