engine coolant CADILLAC STS 2006 1.G User Guide

After you have removed the sight shields (if equipped) on the 3.6L V6 engine, here is what you will see:
A. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-106.
B. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-40.
C. Battery. SeeBattery on page 5-44.
D. Passenger Compartment Air Filter. SeePassenger
Compartment Air Filter on page 3-55.
E. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-39.F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-18.
G. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 5-18.
H. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-41.
I. Engine Coolant Surge Tank and Pressure Cap. See
Coolant Surge Tank Pressure Cap on page 5-30
andCooling System on page 5-32.
J. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-24.
5-13

After you have removed the sight shields (if equipped) on the 4.6L V8 engine, here is what you will see:
A. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-106.
B. Battery. SeeBattery on page 5-44.
C. Passenger Compartment Air Filter. SeePassenger
Compartment Air Filter on page 3-55.
D. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-40.
E. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-39.
F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-18.G. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 5-18.
H. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-41.
I. Engine Coolant Surge Tank and Pressure Cap. See
Coolant Surge Tank Pressure Cap on page 5-30
andCooling System on page 5-32.
J. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-24.
5-15

After you have removed the sight shields (if equipped) on the 4.4L V8 STS-V engine, here is what you will see:
A. Battery. SeeBattery on page 5-44.
B. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-106.
C. Passenger Compartment Air Filter. SeePassenger
Compartment Air Filter on page 3-55.
D. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-40.
E. Intercooler System Pressure Cap. SeeEngine
Coolant on page 5-26.
F. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-39.
G. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-18.
H. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 5-18.I. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-41.
J. Engine Coolant Surge Tank and Pressure Cap. See
Coolant Surge Tank Pressure Cap on page 5-30
andCooling System on page 5-32.
K. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-24.
If your vehicle is equipped with front compartment
underhood sight shields, before closing the hood be
sure to reinstall the sight shields. To reinstall the shields,
locate the tabs on the left and right sides and insert
them into the openings in the tower to tower brace.
Then insert the fasteners into the top of the shield and
push the fasteners back into place.
5-17

Engine Air Cleaner/Filter
The engine air cleaner/lter is in the engine
compartment on the driver’s side of the vehicle, near
the front. SeeEngine Compartment Overview on
page 5-12for more information on locating the air
cleaner/lter.
When to Inspect the Engine
Air Cleaner/Filter
Inspect the air cleaner/lter at the MaintenanceII
intervals and replace it at the rst oil change after each
50,000 mile (83 000 km) interval. SeeScheduled
Maintenance on page 6-4for more information. If you
are driving in dusty/dirty conditions, inspect the lter
at each engine oil change.
How to Inspect the Engine
Air Cleaner/Filter
To inspect the air cleaner/lter remove the lter from
the vehicle and lightly shake the lter to release
loose dust and dirt. If the lter remains caked with dirt,
a new lter is required.
To inspect or replace the lter in the 3.6L V6 or
4.6L V8 engines, do the following:
1. Remove the two screws located on the top of
the cover.
2. Disconnect the coolant recovery hose so that it
is not going across the top of the engine air
cleaner/lter.
3. Loosen the clamp and remove the duct from the
passenger’s side of the engine air cleaner/lter. 4.6L V8 Engine shown, 3.6L V6 Engine similar
5-24

Automatic Transmission Fluid
How to Check Automatic
Transmission Fluid
It is not necessary to check the transmission uid level.
A transmission uid leak is the only reason for uid
loss. If a leak occurs, take the vehicle to the dealership
service department and have it repaired as soon as
possible.
There is a special procedure for checking and changing
the transmission uid. Because this procedure is
difficult, you should have this done at the dealership
service department. Contact your dealer for additional
information or the procedure can be found in the service
manual. To purchase a service manual, seeService
Publications Ordering Information on page 7-14.
Notice:Use of the incorrect automatic transmission
uid may damage your vehicle, and the damages
may not be covered by your warranty. Always
use the automatic transmission uid listed in
Recommended Fluids and Lubricants on page 6-12.
Change the uid and lter at the intervals listed in
Additional Required Services on page 6-6, and be sure
to use the uid listed inRecommended Fluids and
Lubricants on page 6-12.
Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for ve years or 150,000 miles
(240 000 km), whichever occurs rst, if you add only
DEX-COOL
®extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem with
engine overheating, seeEngine Overheating on
page 5-30.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they
should.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at the rst maintenance
service after each 30,000 miles (50 000 km) or
24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-26

What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL®coolant which will not damage
aluminum parts. If you use this coolant mixture, you do
not need to add anything else.
{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:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost would not be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and
other parts.
If you have to add coolant more than once or twice a
year, have your dealer check your cooling system.
Notice:If you use extra inhibitors and/or additives
in your vehicle’s cooling system, you could
damage your vehicle. Use only the proper mixture
of the engine coolant listed in this manual for
the cooling system. SeeRecommended Fluids and
Lubricants on page 6-12for more information.
5-27

Checking Coolant
The coolant surge tank and pressure cap are located on
the driver’s side of the vehicle, toward the rear of the
engine compartment. SeeEngine Compartment
Overview on page 5-12for more information on location.
{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure
cap — even a little — when the engine and
radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the FULL
COLD/FROID line on the side of the surge tank.
Follow the arrow from the top of the tank down the side
to the horizontal mark.
If the CHECK COOLANT LEVEL message in the Driver
Information Center (DIC) comes on and stays on, it
means you are low on engine coolant. SeeDIC
Warnings and Messages on page 3-79for more
information.
5-28

Checking Intercooler System Coolant
(4.4L V8 STS-V Engine Only)
SeeEngine Compartment Overview on page 5-12for
the location of the intercooler system pressure cap.
Notice:This vehicle has a specic coolant ll
procedure. Failure to follow this procedure could
cause your engine to overheat and be severely
damaged.
Park the vehicle on a level surface and turn off the
engine. When the engine is cold, the coolant level
should be at or above the FULL COLD line. The
FULL COLD line has an arrow pointing to it.
Adding Coolant
If you need more coolant, add the proper DEX-COOL®
coolant mixture at the intercooler ll neck, but only
when the engine is cool. SeeCooling System on
page 5-32for instructions on how to add coolant to
the intercooler ll neck.
{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.
When replacing a pressure cap, make sure it is
hand-tight and fully seated.
5-29

Coolant Surge Tank Pressure Cap
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank. SeeEngine
Compartment Overview on page 5-12for more
information on location.
Engine Overheating
You will nd an ENGINE COOLANT HOT IDLE
ENGINE, an ENGINE OVERHEATED STOP ENGINE
and a CHECK COOLANT LEVEL message displayed in
the Driver Information Center (DIC). SeeDIC Warnings
and Messages on page 3-79for more information.
There is also a coolant temperature gage and a coolant
warning light on the instrument panel. SeeEngine
Coolant Temperature Gage on page 3-67andEngine
Coolant Temperature Warning Light on page 3-66
for more information.
If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Just turn it off and get everyone away
from the vehicle until it cools down. Wait until
there is no sign of steam or coolant before you
open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch re. You
or others could be badly burned. Stop your
engine if it overheats, and get out of the vehicle
until the engine is cool.
SeeOverheated Engine Protection Operating
Mode on page 5-31for information on driving to
a safe place in an emergency.
Notice:If your engine catches re because you keep
driving with no coolant, your vehicle can be badly
damaged. The costly repairs would not be covered by
your warranty. SeeOverheated Engine Protection
Operating Mode on page 5-31for information on
driving to a safe place in an emergency.
5-30

If No Steam Is Coming From
Your Engine
An overheat warning, along with a CHECK COOLANT
LEVEL message, can indicate a serious problem.
If you get an engine overheat warning with no CHECK
COOLANT LEVEL message, but see or hear no
steam, the problem may not be too serious. Sometimes
the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it is safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL (N) and let the
engine idle.
2. Set the climate controls to the highest heat setting
and fan speed and open the windows, as
necessary.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.If the warning continues and you have not stopped,
pull over, stop, and park your vehicle right away.
If there is still no sign of steam, you can idle the engine
for three minutes while you are parked. If you still have
the warning, turn off the engine and get everyone out of
the vehicle until it cools down. Also, see “Overheated
Engine Protection Operating Mode” later in this section.
You may decide not to lift the hood but to get service
help right away.
Overheated Engine Protection
Operating Mode
This operating mode allows your vehicle to be driven to
a safe place in an emergency. Should an overheated
engine condition exist, an overheat protection mode
which alternates ring groups of cylinders helps prevent
engine damage. In this mode, you will notice a loss
in power and engine performance. A low coolant and/or
engine overheat warning will indicate that an overheat
condition exists. Driving extended miles (km) and/or
towing a trailer in the overheat protection mode should
be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair the
cause of coolant loss and change the oil. SeeEngine
Oil on page 5-18.
5-31