2011 CADILLAC STS engine

Black plate (18,1)Cadillac STS Owner Manual - 2011
Selecting the Right Engine Oil
Selecting the right engine oil depends on both the
proper oil specification and viscosity grade:
Specification
Use and ask for engine oils with the dexos™
certification mark. Oils meeting the requirements of your
vehicle should have the dexos™certification mark on
the container. This certification mark indicates that the
oil has been approved to the dexos™ specification.
Your vehicle was filled at the factory with dexos™
approved engine oil. Notice:
Use only engine oil that is approved to the
dexos™ specification or an equivalent engine oil
of the appropriate viscosity grade. Engine oils
approved to the dexos™ specification will show the
dexos™ symbol on the container. Failure to use the
recommended engine oil or equivalent can result in
engine damage not covered by the vehicle warranty.
If you are unsure whether your oil is approved to
the dexos™ specification, ask your service provider.
Use of Substitute Engine Oils if dexos™ is unavailable:
In the event that dexos™ approved engine oil is not
available at an oil change or for maintaining proper oil
level, you may use substitute engine oil displaying the
API Starburst symbol and of SAE 5W-30 viscosity
grade. Use of oils that do not meet the dexos™
specification, however, may result in reduced
performance under certain circumstances.
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Black plate (19,1)Cadillac STS Owner Manual - 2011
Viscosity Grade
SAE 5W-30 is the best viscosity grade for the vehicle.
Do not use other viscosity oils such as SAE 10W‐30,
10W‐40, or 20W-50.
Cold Temperature Operation: In an area of extreme
cold, where the temperature falls below−29°C (−20°F),
an SAE 0W-30 oil should be used. An oil of this viscosity grade will provide easier cold starting for the
engine at extremely low temperatures. When selecting
an oil of the appropriate viscosity grade, be sure to
always select an oil that meets the required
specification, dexos™. See
“Specification”for more
information.
Engine Oil Additives/Engine Oil Flushes
Do not add anything to the oil. The recommended oils
with the dexos™ specification and displaying the
dexos™ certification mark are all that is needed for
good performance and engine protection.
Engine oil system flushes are not recommended and
could cause engine damage not covered by the vehicle
warranty.
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Black plate (20,1)Cadillac STS Owner Manual - 2011
What to Do with Used Oil
Used engine oil contains certain elements that can be
unhealthy for your skin and could even cause cancer.
Do not let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good hand
cleaner. Wash or properly dispose of clothing or rags
containing used engine oil. See the manufacturer's
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from
the filter before disposal. Never dispose of oil by putting
it in the trash or pouring it on the ground, into sewers,
or into streams or bodies of water. Recycle it by taking it
to a place that collects used oil.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that indicates when
to change the engine oil and filter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change is indicated can vary considerably.
For the oil life system to work properly, the system must
be reset every time the oil is changed.When the system has calculated that oil life has been
diminished, it indicates that an oil change is necessary.
A CHANGE ENGINE OIL SOON message in the DIC
comes on. See
DIC Warnings and Messages
on
page 4‑76. Change the oil as soon as possible within
the next 600 miles (1 000 km). It is possible that,
if driving under the best conditions, the oil life system
might indicate that an oil change is not necessary for up
to a year. The engine oil and filter must be changed at
least once a year and, at this time, the system must be
reset. Your dealer has trained service people who will
perform this work and reset the system. It is also
important to check the oil regularly over the course of
an oil drain interval and keep it at the proper level.
If the system is ever reset accidentally, the oil must be
changed at 3,000 miles (5 000 km) since the last oil
change. Remember to reset the oil life system
whenever the oil is changed.
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Black plate (21,1)Cadillac STS Owner Manual - 2011
How to Reset the Engine Oil Life
System
Reset the system whenever the engine oil is changed
so that the system can calculate the next engine oil
change. To reset the system:1. Press the up or down arrow to scroll the DIC to show OIL LIFE.
2. Once the XXX% ENGINE OIL LIFE menu item is highlighted, press and hold the RESET button until
the percentage shows 100%.
If the percentage does not return to 100% or if the
CHANGE ENGINE OIL SOON message comes back on
when the vehicle is started, the engine oil life system
has not been reset. Repeat the procedure.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the engine
compartment on the driver's side of the vehicle, near
the front. See Engine Compartment Overview
on
page 6‑13for more information on locating the air
cleaner/filter.
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Black plate (22,1)Cadillac STS Owner Manual - 2011
When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/filter at the scheduled
maintenance intervals and replace it at the first oil
change after each 80 000 km (50,000 mile) interval. See
Scheduled Maintenance
on page 7‑3for more
information. If you are driving in dusty/dirty conditions,
inspect the filter at each engine oil change.
How to Inspect the Engine Air
Cleaner/Filter
To inspect the air cleaner/filter remove the filter from the
vehicle and lightly shake the filter to release loose dust
and dirt. If the filter remains caked with dirt, a new filter
is required.
To inspect or replace the filter:
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/
filter.
3. Loosen the clamp and remove the duct from the passenger's side of the engine air cleaner/filter. 4. The two sides of the airbox are hinged at the
bottom. Open the airbox by pushing the top of the
airbox cover toward the engine.
5. Remove the air filter by lifting it straight up through the opening in the airbox.
6. Inspect or replace the engine air cleaner/filter. See Maintenance Replacement Parts
on page 7‑11for
the correct part number for the filter.
7. Reinstall the cover by reversing Steps 1 through 4.
{WARNING:
Operating the engine with the air cleaner/filter off
can cause you or others to be burned. The air
cleaner not only cleans the air; it helps to stop
flames if the engine backfires. Use caution when
working on the engine and do not drive with the
air cleaner/filter off.
Notice: If the air cleaner/filter is off, dirt can easily
get into the engine, which could damage it. Always
have the air cleaner/filter in place when you are
driving.
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Black plate (24,1)Cadillac STS Owner Manual - 2011
Cooling System
The cooling system allows the engine to maintain the
correct working temperature.
A. Electric Engine Cooling Fan(s) (Out of view)
B. Mechanical Engine Cooling Fan (If equipped)(Out of view)
C. Coolant Surge Tank and Pressure Cap
{WARNING:
An electric engine cooling fan under the hood can
start up even when the engine is not running and
can cause injury. Keep hands, clothing, and tools
away from any underhood electric fan.
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Black plate (25,1)Cadillac STS Owner Manual - 2011
{WARNING:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them. If you
do, you can be burned.
Do not run the engine if there is a leak. If you run
the engine, it could lose all coolant. That could
cause an engine fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
Notice: Using coolant other than DEX-COOL
®can
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant could
require changing sooner, at 50 000 km (30,000 miles)
or 24 months, whichever occurs first. Any repairs
would not be covered by the vehicle warranty.
Always use DEX-COOL (silicate-free) coolant in the
vehicle.
Engine Coolant
The cooling system in the vehicle is filled with
DEX-COOL®engine coolant. This coolant is designed
to remain in the vehicle for five years or 240 000 km
(150,000 miles), whichever occurs first.
The following explains the cooling system and how to
check and add coolant when it is low. If there is a
problem with engine overheating, see Engine
Overheating on page 6‑30
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Black plate (26,1)Cadillac STS Owner Manual - 2011
What to Use
{WARNING:
Adding only plain water or some other liquid to the
cooling system can be dangerous. Plain water
and other liquids, 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 fire and you or
others could be burned. Use a 50/50 mixture of
clean, drinkable water and DEX-COOL coolant.
Use a 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant. If using this mixture, nothing else
needs to be added. This mixture:
.Gives freezing protection down to −34°F (−37°C),
outside temperature.
.Gives boiling protection up to 265°F (129°C),
engine temperature.
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine temperature.
Notice: If an improper coolant mixture is used, the
engine could overheat and be badly damaged. The
repair cost would not be covered by the vehicle
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and
other parts.
Notice: If extra inhibitors and/or additives are used
in the vehicle's cooling system, the vehicle could be
damaged. Use only the proper mixture of the engine
coolant listed in this manual for the cooling system.
See Recommended Fluids and Lubricants
on
page 7‑9for more information.
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