2015 CADILLAC CTS SEDAN engine

Black plate (12,1)Cadillac CTS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707478) - 2015 - crc - 10/1/14
10-12 Vehicle Care
{Caution
Failure to use the recommended
engine oil can result in engine
damage not covered by the
vehicle warranty. Check with your
dealer or service provider on
whether the oil is approved to the
dexos1 specification.
Viscosity Grade
Use SAE 5W-30 viscosity grade
engine oil.
Cold Temperature Operation: In an
area of extreme cold, where the
temperature falls below −29 °C (−20
°F), an SAE 0W-30 oil may 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,
always select an oil of the correct
specification. See “Specification”
earlier in this section.
Engine Oil Additives/Engine
Oil Flushes
Do not add anything to the oil. The
recommended oils meeting the
dexos1 specification 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.
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 a combination of factors which
include engine revolutions, engine
temperature, and miles driven.
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 comes on. See
Engine Oil Messages on page 5-39.

Black plate (13,1)Cadillac CTS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707478) - 2015 - crc - 10/1/14
Vehicle Care 10-13
Change the oil as soon as possible
within the next 1 000 km (600 mi).
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 5 000 km (3,000 mi)
since the last oil change.
Remember to reset the oil life
system whenever the oil is changed.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. Using the DIC buttons, displayREMAINING OIL LIFE on the
DIC. See Driver Information
Center (DIC) on page 5-29 and
Engine Oil Messages on
page 5-39.
2. Press the SEL button and hold to clear the CHANGE ENGINE
OIL SOON message and reset
the oil life at 100%.
Be careful not to reset the oil life
display accidentally at any time
other than after the oil is
changed. It cannot be reset
accurately until the next oil
change. The oil life system can also be reset
as follows:
1. Turn the ignition on with the
engine off.
2. Fully press and release the accelerator pedal three times
within five seconds.
If the CHANGE ENGINE OIL
SOON message is not on, the
system is reset.
The system is reset when the
CHANGE ENGINE OIL SOON
message is off.
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.

Black plate (14,1)Cadillac CTS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707478) - 2015 - crc - 10/1/14
10-14 Vehicle Care
Automatic Transmission
Fluid
How to Check Automatic
Transmission Fluid
It is not necessary to check the
transmission fluid level.
A transmission fluid leak is the only
reason for fluid loss. If a leak
occurs, take the vehicle to your
dealer and have it repaired as soon
as possible.
The vehicle is not equipped with a
transmission fluid level dipstick.
There is a special procedure for
checking and changing the
transmission fluid. Because this
procedure is difficult, this should be
done at the dealer. Contact the
dealer for additional information.
Change the fluid and filter at the
intervals listed inMaintenance
Schedule on page 11-3, and be sure
to use the fluid listed in
Recommended Fluids and
Lubricants on page 11-13.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the
engine compartment on the driver
side of the vehicle. See Engine
Compartment Overview on
page 10-5 for location.
When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/filter at the
scheduled maintenance intervals.
SeeMaintenance Schedule on
page 11-3. 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 engine air cleaner/
filter, remove the filter from the
vehicle and lightly shake the filter to
release loose dust and dirt. If the
filter remains covered with dirt, a
new filter is required. To inspect or replace the air cleaner/
filter:
2.0L L4 LTG Engine
1. Air Duct Clamp
2. Electrical Connector
3. Screws
1. Disconnect the outlet duct by
loosening the air duct clamp (1).
2. Disconnect the electrical connector (2) and wiring
attachment to cover.
3. Remove the screws (3) on top of the cover.

Black plate (15,1)Cadillac CTS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707478) - 2015 - crc - 10/1/14
Vehicle Care 10-15
4. Lift the filter cover housing awayfrom the engine.
5. Pull out the filter.
6. Inspect or replace the engine air cleaner/filter.
7. Reverse Steps 1–5 to reinstall the filter cover housing.
3.6L V6 LFX Engine
1. Air Duct Clamp
2. Electrical Connector
3. Screws
1. Disconnect the outlet duct byloosening the air duct clamp (1). 2. Disconnect the electrical
connector (2) and wiring
attachment to cover.
3. Remove the screws (3) on top of the cover.
4. Lift the filter cover housing away from the engine.
5. Pull out the filter.
6. Inspect or replace the engine air cleaner/filter.
7. Reverse Steps 1–5 to reinstall the filter cover housing.
3.6L V6 LF3 Engine
1. Lower Air Duct Clamp
2. Lower Electrical Connector
3. Upper Air Duct Clamp
4. Upper Electrical Connector
5. Screws
1. Disconnect the lower and upperoutlet ducts by loosening the
lower (1) and upper (3) air duct
clamps.
2. Disconnect the lower (2) and upper (4) electrical connectors
and wiring attachments to cover.

Black plate (16,1)Cadillac CTS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707478) - 2015 - crc - 10/1/14
10-16 Vehicle Care
3. Remove the screws (5) on top ofthe cover.
4. Lift the filter cover housing away from the engine.
5. Pull out the filter.
6. Inspect or replace the engine air cleaner/filter.
7. Reverse Steps 1–5 to reinstall the filter cover housing.
{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.
{Caution
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.
Cooling System
The cooling system allows the
engine to maintain the correct
working temperature.
2.0L L4 LTG Engine
1. Engine Coolant Surge Tank
and Pressure Cap
2. Engine Cooling Fan (Out of View)

Black plate (17,1)Cadillac CTS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707478) - 2015 - crc - 10/1/14
Vehicle Care 10-17
3.6L V6 LFX Engine
1. Engine Coolant Surge Tankand Pressure Cap
2. Engine Cooling Fan (Out of View)
3.6L V6 LF3 Engine
1. Engine Coolant Surge Tankand Pressure Cap
2. Engine Cooling Fan (Out of View)
{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.
{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.
{Caution
Using coolant other than
DEX-COOL®can cause
premature engine, heater core,
or radiator corrosion. In addition,
the engine coolant could require
changing sooner. Any repairs
would not be covered by the
(Continued)

Black plate (18,1)Cadillac CTS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707478) - 2015 - crc - 10/1/14
10-18 Vehicle Care
Caution (Continued)
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. SeeMaintenance Schedule
on page 11-3 andRecommended
Fluids and Lubricants on
page 11-13.
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 10-21.
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 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. This mixture:
.Gives freezing protection down
to −37°C (−34°F), outside
temperature.
.Gives boiling protection up to
129°C (265°F), engine
temperature.
.Protects against rust and
corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine
temperature.
{Caution
If improper coolant mixture,
inhibitors, or additives are used in
the vehicle cooling system, the
engine could overheat and be
damaged. Too much water in the
mixture can freeze and crack
engine cooling parts. The repairs
would not be covered by the
vehicle warranty. Use only the
proper mixture of engine coolant
for the cooling system. See
Recommended Fluids and
Lubricants on page 11-13.

Black plate (19,1)Cadillac CTS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707478) - 2015 - crc - 10/1/14
Vehicle Care 10-19
Never dispose of engine coolant by
putting it in the trash, pouring it on
the ground, or into sewers, streams,
or bodies of water. Have the coolant
changed by an authorized service
center, familiar with legal
requirements regarding used
coolant disposal. This will help
protect the environment and your
health.
Checking Coolant
The vehicle must be on a level
surface when checking the coolant
level.
It is normal to see coolant moving in
the upper coolant hose return line
when the engine is running. It is
also normal to see bubbles entering
the surge tank through the
small hose.
Check to see if coolant is visible in
the coolant surge tank. If the coolant
inside the coolant surge tank is
boiling, do not do anything else until
it cools down.If coolant is visible but the coolant
level is not at or above the COLD
FILL line, add a 50/50 mixture of
clean drinkable water and
DEX-COOL coolant.
Be sure the cooling system is cool
before this is done.
If no coolant is visible in the coolant
surge tank, add coolant as follows:
How to Add Coolant to the
Coolant Surge Tank
{Caution
This vehicle has a specific
coolant fill procedure. Failure to
follow this procedure could cause
the engine to overheat and be
severely damaged.
If no problem is found, check to see
if coolant is visible in the coolant
surge tank. If coolant is visible but
the coolant level is not at the bottom
of the fill neck, 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.
{Warning
Steam and scalding liquids from a
hot cooling system can blow out
and burn you badly. Never turn
the cap when the cooling system,
including the surge tank pressure
cap, is hot. Wait for the cooling
system and surge tank pressure
cap to cool.
{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 coolant warning system is set
(Continued)