engine coolant CADILLAC STS 2009 1.G Owner's Manual

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.
5-32

How to Add Coolant to the
Intercooler System Fill Neck
(4.4L V8 STS-V Engine Only)
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 5-27for
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.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.
5-33

3. Add the proper DEX-COOL®coolant mixture to the
ll neck, until the coolant reaches the COLD FILL
line on the ll neck.
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.
4. 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.
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.
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
The vehicle has several indicators to warn of engine
overheating.
There are two engine hot messages that could be
displayed in the Driver Information Center (DIC).
SeeDIC Warnings and Messages on page 3-79
DIC Warnings and Messages for more information.
If the engine is overheating, then you will nd a coolant
temperature gage and a coolant warning light on the
instrument panel. SeeEngine Coolant Temperature
Gage on page 3-65andEngine Coolant Temperature
Warning Light on page 3-64for more information.
5-34

You may decide not to lift the hood when this warning
appears, but instead get service help right away.
SeeRoadside Service on page 7-7.
If you do decide to lift the hood, make sure the vehicle
is parked on a level surface.
Then check to see if the engine cooling fans are
running. If the engine is overheating, both fans should
be running. If they are not, do not continue to run
the engine and have the vehicle serviced.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
Overheated Engine Protection Operating Mode on
page 5-36for information on driving to a safe place
in an emergency.
Notice:If the engine catches re while driving
with no coolant, the vehicle can be badly damaged.
The costly repairs would not be covered by the
vehicle warranty. SeeOverheated Engine Protection
Operating Mode on page 5-36for information on
driving to a safe place in an emergency.If Steam Is Coming From The Engine
Compartment
{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. 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 the vehicles engine is
overheated, the liquids in it can catch re. You or
others could be badly burned. Stop the engine if it
overheats, and get out of the vehicle until the
engine is cool.
SeeOverheated Engine Protection Operating Mode
on page 5-36for information on driving to a safe
place in an emergency.
5-35

If No Steam Is Coming From The
Engine Compartment
An overheat warning, can indicate a serious problem.
If an engine overheat warning is displayed but no steam
can be seen or heard, the problem may not be too
serious. Sometimes the engine can get a little too hot
when the vehicle:
Climbs a long hill on a hot day.
Stops after high-speed driving.
Idles for long periods in traffic.
Tows a trailer.
If the overheat warning is displayed with no sign of
steam:
1. Turn the air off.
2. Turn the heater on to the highest temperature and
to the highest fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral)
while stopped. If it is safe to do so, pull off the
road, shift to P (Park) or N (Neutral) and let
the engine idle.
If the engine coolant temperature gage is no longer
in the overheat zone or an overheat warning no longer
displays, the vehicle can be driven. Continue to drive the
vehicle slow for about 10 minutes. Keep a safe vehicle
distance from the car in front of you. If the warning does
not come back on, continue to drive normally.If the warning continues, pull over, stop, and park the
vehicle right away.
If there is no sign of steam, idle the engine for
three minutes while parked. If the warning is still
displayed, turn off the engine until it cools down.
Also, see″Overheated Engine Protection Operating
Mode″later in this section.
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. An 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.
5-36

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 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.
5-38

When the CHANGE ENGINE OIL SOON message
appears, the following services, checks, and inspections
are required:
❑Change engine oil and lter. SeeEngine Oil on
page 5-18. Reset oil life system. SeeEngine Oil Life
System on page 5-21.An Emission Control Service.
❑Visually check for any leaks or damage.
See footnote (k).
❑Inspect engine air cleaner lter. If necessary, replace
lter. SeeEngine Air Cleaner/Filter on page 5-23.
See footnote (m).
❑Check tires for ination pressures and wear. SeeTires
on page 5-54. If tire rotation is recommended for the
vehicle, rotate tires. SeeTire Inspection and Rotation
on page 5-71and “Tire Wear Inspection” inAt Least
Once a Month on page 6-11.❑Inspect brake system.See footnote (a).
❑Check engine coolant and windshield washer uid
levels. If the vehicle has the 4.4L V8 supercharged
engine, check intercooler uid level. Add uid as
needed.
❑Perform any needed additional services. See
“Additional Required Services” in this section.
❑Inspect suspension and steering components.
See footnote (b).
❑Inspect engine cooling system.See footnote (c).
❑Inspect wiper blades.See footnote (d).
❑Inspect restraint system components.
See footnote (e).
❑Lubricate body components.See footnote (f).
6-5

(i)If using DOT-4 brake fluid only: Drain, flush, and refill
brake hydraulic system at a regular maintenance service
every two years. This service can be complex; you should
have your dealer/retailer perform this service. See Brakes
on page 5-39.
(j)Drain, flush, and refill cooling system. This service can
be complex; you should have your dealer/retailer perform
this service. See Engine Coolant on page 5-27 for what to
use. Inspect hoses. Clean radiator, condenser, pressure
cap, and filler neck. Pressure test the cooling system and
pressure cap.
(k)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired
and the fluid level checked. Add fluid if needed.
(l)Drain, flush, and refill intercooler system. This service
can be complex; you should have your dealer/retailer
perform this service. See Engine Coolant on page 5-27.
(m)If driving regularly under dusty conditions, inspect
the filter at each engine oil change.
(n)Visually inspect belt for fraying, excessive cracks, or
obvious damage. Replace belt if necessary.(p)If the vehicle has the 3.6L V6 (VIN Code V) engine,
replace the engine air cleaner filter every 40,000 miles
(64 000 km).
(q)Check vent hose at transfer case for kinks and proper
installation. Check to be sure vent hose is unobstructed,
clear, and free of debris. During any maintenance, if a
power washer is used to clean mud and dirt from the
underbody, care should be taken to not directly spray the
transfer case output seals. High pressure water can
overcome the seals and contaminate the transfer case
fluid. Contaminated fluid will decrease the life of the
transfer case and should be replaced.
(r)Change transfer case fluid if the vehicle is mainly
driven under one or more of these conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as high performance operation or taxi,
police, or delivery service.
6-9

Owner Checks and Services
These owner checks and services should be performed
at the intervals specied to help ensure vehicle safety,
dependability, and emission control performance. Your
dealer/retailer can assist with these checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to the
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-13.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel fill.
Engine Oil Level Check
Notice:It is important to check the engine oil
regularly and keep it at the proper level. Failure to
keep the engine oil at the proper level can cause
damage to the engine not covered by the vehicle
warranty.
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-18.
Engine Coolant Level Check
Check the engine coolant level and add DEX-COOL®
coolant mixture if necessary. SeeEngine Coolant
on page 5-27.
Intercooler Coolant Level Check
(4.4L Supercharged Engine)
Check the coolant level and add DEX-COOL®coolant
mixture if necessary. SeeEngine Coolant on page 5-27.
Windshield Washer Fluid Level
Check
Check the windshield washer uid level in the windshield
washer uid reservoir and add the proper uid if
necessary. SeeWindshield Washer Fluid on page 5-38.
6-10

To check the P (Park) mechanism’s holding ability:
With the engine running, shift to P (Park). Then
release the parking brake followed by the regular
brake.
Contact your dealer/retailer if service is required.
Underbody Flushing Service
At least every spring, use plain water to ush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
Tire Sealant and Compressor Kit
If the vehicle has a Tire Sealant and Compressor Kit,
check the sealant expiration date printed on the
instruction label of the kit at least once a year.
See your dealer/retailer for a replacement canister.
Recommended Fluids and
Lubricants
Fluids and lubricants identied below by name, part
number, or specication can be obtained from your
dealer/retailer.
Usage Fluid/Lubricant
Engine OilThe engine requires a special engine
oil meeting GM Standard GM4718M.
Oils meeting this standard can be
identied as synthetic, and should
also be identied with the American
Petroleum Institute (API) Certied for
Gasoline Engines starburst symbol.
However, not all synthetic API oils
with the starburst symbol will meet
this GM standard. Look for and use
only oil that meets GM Standard
GM4718M. For the proper viscosity,
seeEngine Oil on page 5-18.
Engine Cooling
System50/50 mixture of clean, drinkable
water and use only DEX-COOL
®
Coolant. SeeEngine Coolant on
page 5-27.
6-13