CADILLAC CT4 2023 Owners Manual

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
380 Vehicle Care
Add enough oil to put the level
somewhere in the proper
operating range. Push the
dipstick all the way back in
when finished.
Selecting the Right
Engine Oil
Selecting the right engine oil
depends on both the proper
oil specification and viscosity
grade. See Recommended
Fluids and Lubricants0474.
Specification
Use full synthetic engine oils
that meet the dexos1
specification. Engine oils that
have been approved by
GM as meeting the dexos1
specification are marked with
the dexos1 approved logo. See
www.gmdexos.com.
Caution
Failure to use the
recommended engine oil or
equivalent can result in
engine damage not covered
by the vehicle warranty.
Viscosity Grade
For the LSY 2.0L L4 turbo
engine, use SAE 0W-20
viscosity grade engine oil.
For the L3B 2.7L L4 turbo and
LF4 3.6L V6 twin turbo
engines, 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, it
is recommended to 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

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 381
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 atwhich 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.
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, display REMAINING OIL
LIFE on the DIC. See Driver
Information Center (DIC)
(Base Level) 0129 or
Driver Information Center
(DIC) (Uplevel) 0132.
2. Press and hold the thumbwheel on the
steering wheel. When the

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
382 Vehicle Care
confirmation message
displays, select YES. The
oil life will change to 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. Using the DIC buttons, display REMAINING OIL
LIFE on the DIC. See Driver
Information Center (DIC)
(Base Level) 0129 or
Driver Information Center
(DIC) (Uplevel) 0132.
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.
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 your
dealer for additional
information.
Caution
Use of the incorrect
automatic transmission fluid
may damage the vehicle, and
the damage may not be
covered by the vehicle
warranty. Always use the
correct automatic
transmission fluid. See
Recommended Fluids and
Lubricants
0474.
Change the fluid and filter at
the intervals listed in
Maintenance Schedule 0469,
and be sure to use the fluid
listed in Recommended Fluids
and Lubricants 0474.
Manual Transmission
Fluid
It is not necessary to check
the manual 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

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Vehicle Care 383
possible. See Recommended
Fluids and Lubricants0474
for the proper fluid to use.
Hydraulic Clutch
For vehicles with a manual
transmission, it is not
necessary to regularly check
brake/clutch fluid unless there
is a leak suspected. Adding
fluid will not correct a leak.
A fluid loss in this system
could indicate a problem. Have
the system inspected and
repaired.
When to Check and What
to Use
The brake/hydraulic clutch
fluid reservoir cap has this
symbol on it. See Engine
Compartment Overview 0373
for reservoir location. The common hydraulic clutch
and brake master cylinder fluid
reservoir is filled with brake
fluid as indicated on the
reservoir cap. See Brake Fluid
0
398 for brake fluid to use.
How to Check and Add
Fluid
Visually check the brake/
clutch fluid reservoir to make
sure the fluid level is at the
MIN (minimum) line on the side
of the reservoir. The brake/
hydraulic clutch fluid system
should be closed and sealed.
Do not remove the cap to
check the fluid level or to
top-off the fluid level. Remove
the cap only when necessary
to add the proper fluid until
the level reaches the MIN line.
Engine Air Filter Life
System
This feature provides the
engine air filter’s remaining life
and best timing for a change.
The timing to change an engine air filter depends on
driving and environmental
conditions.
When to Change the
Engine Air Filter
When the Driver Information
Center (DIC) displays a
message to replace the engine
air filter at the next oil change,
follow this timing.
When the DIC displays a
message to replace the engine
air filter soon, replace the
engine air filter at the earliest
convenience.
The system must be reset
after the engine air filter is
changed.
If the DIC displays a message
to check the engine air filter
system, see your dealer.
How to Reset the Engine
Air Filter Life System
To reset:
1. Place the vehicle in P (Park).

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
384 Vehicle Care
2. Display the Air Filter Lifeon the DIC. See Driver
Information Center (DIC)
(Base Level) 0129 or
Driver Information Center
(DIC) (Uplevel) 0132.
3. Press
Ton the steering
wheel, or press the trip
odometer reset stem if the
vehicle does not have DIC
controls, to move to the
Reset/Disable display area.
Select Reset, then press
the thumbwheel or press
the reset stem for several
seconds.
4. Press the thumbwheel or the reset stem to confirm
the reset.
Engine Air
Cleaner/Filter
The engine air cleaner/filter is
in the engine compartment on
the passenger side of the
vehicle for the 2.0L L4 and
2.7L L4 engines, and in the
center of the engine compartment for the 3.6L
V6 engine. See Engine
Compartment Overview
0373.
When to Inspect the
Engine Air Cleaner/Filter
.For intervals on changing
and inspecting the engine air
filter, see Maintenance
Schedule 0469.
.If equipped with Engine Air
Filter Life System, see
Engine Air Filter Life System
0383.
.If driving in very dusty areas,
follow the engine air filter
inspecting and changing
intervals, see Maintenance
Schedule 0469.
How to Inspect/Replace
the Engine Air
Cleaner/Filter
Do not start the engine or
have the engine running with
the engine air cleaner/filter
housing open. Before
removing the engine air
cleaner/filter, make sure that
the engine air cleaner/filter housing and nearby
components are free of dirt
and debris.
Do not clean the engine air
cleaner/filter or components
with water or compressed air.
{Warning
Operating the engine with
the air cleaner/filter off can
cause you or others to be
burned. Use caution when
working on the engine. Do
not start the engine or drive
the vehicle with the air
cleaner/filter off, as flames
may be present if the engine
backfires.
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
driving.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 385
To inspect or replace the air
cleaner/filter:
2.0L L4 Engine Shown, 2.7LL4 Engine Similar
1. Remove the five screws on top of the air cleaner/filter
cover.
2. Lift the air/cleaner/filter cover away from the air
cleaner/filter housing.
3. Pull out the air cleaner/filter.
{Warning
If part replacement is
necessary, the part must be
replaced with one of the
same part number or with an
equivalent part. Use of a
replacement part without
the same fit, form, and
function may result in
personal injury or damage to
the vehicle.
4. Inspect or replace the air cleaner/filter.
5. Reverse Steps 1–3 to reinstall the air
cleaner/filter cover.
6. If equipped, reset the engine air filter life system
after replacing the engine
air filter. See Engine Air
Filter Life System 0383.
3.6L V6 Engine
1. Air Duct Clamps
2. Electrical Connectors
3. Screws
1. Disconnect the harness
connectors from the air
cleaner/filter cover
electrical connectors (2).
2. Loosen the screws on the air duct clamps (1) holding
the air outlet ducts in
place. Do not remove
clamps. Move the ducts
aside.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
386 Vehicle Care
3. Remove the 13 screws (3)on top of the engine air
cleaner/filter cover to gain
access to both air
cleaner/filters.
4. Lift the engine air cleaner/filter cover.
5. Lift and remove one or both engine air
cleaner/filters.
{Warning
If part replacement is
necessary, the part must be
replaced with one of the
same part number or with an
equivalent part. Use of a
replacement part without
the same fit, form, and
function may result in
personal injury or damage to
the vehicle.
6. Inspect or replace one or both engine air cleaner/
filters. 7. Reverse Steps 1–4 to
reinstall the engine air
cleaner/filter cover.
8. If equipped, reset the engine air filter life system
after replacing the engine
air filter. See Engine Air
Filter Life System 0383.
Cooling System
The cooling system allows the
engine to maintain the correct
working temperature.
2.0L L4 Engine
1. Engine Coolant Surge
Tank and Pressure Cap
2. Engine Cooling Fan (Out of View)
2.7L L4 Engine
1. Engine Coolant SurgeTank and Pressure Cap
2. Engine Cooling Fan (Out of View)
3. Cooling System Air Bleeder Cap

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 387
3.6L V6 Engine
1. Engine Coolant SurgeTank and Pressure Cap
2. Engine Cooling Fan (Out of View)
{Warning
An underhood electric fan
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
Do not touch heater or
radiator hoses, or other
engine parts. They can be
very hot and can burn you.
Do not run the engine if
there is a leak; all coolant
could leak out. That could
cause an engine fire and can
burn you. Fix any leak before
driving the vehicle.
Engine Coolant
The cooling system in the
vehicle is filled with
DEX-COOL engine coolant.
See Maintenance Schedule
0469 and
Recommended Fluids and
Lubricants 0474.
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 0391.
What to Use
{Warning
Do not touch heater or
radiator hoses, or other
engine parts. They can be
very hot and can burn you.
Do not run the engine if
there is a leak; all coolant
could leak out. That could
cause an engine fire and can
burn you. Fix any leak before
driving the vehicle.
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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
388 Vehicle Care
.Helps keep the proper
engine temperature.
Caution
Do not use anything other
than a mix of DEX-COOL
coolant that meets GM
Standard GMW3420 and
clean, drinkable water.
Anything else can cause
damage to the engine
cooling system and the
vehicle, which would not be
covered by the vehicle
warranty.
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 indicated mark, add a
50/50 mixture of clean
drinkable water and
DEX-COOL coolant.
Be sure the cooling system is
cool before this is done.

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Vehicle Care 389
If no coolant is visible in the
coolant surge tank, add
coolant as follows:
How to Add Coolant to the
Coolant Surge Tank
{Warning
Spilling coolant on hot
engine parts can burn you.
Coolant contains ethylene
glycol and it will burn if the
engine parts are hot enough.
{Warning
Plain water, or other liquids
such as alcohol, can boil
before the proper coolant
mixture will. With plain water
or the wrong mixture, the
engine could get too hot but
there would not be an
overheat warning. The
engine could catch fire and
you or others could be
burned.
{Warning
Steam and scalding liquids
from a hot cooling system
are under pressure. Turning
the pressure cap, even a
little, can cause them to
come out at high speed and
you could be burned. Never
turn the cap when the
cooling system, including the
pressure cap, is hot. Wait for
the cooling system and
pressure cap to cool.
Caution
Failure to follow the specific
coolant fill procedure could
cause the engine to
overheat and could cause
system damage. If coolant is
not visible in the surge tank,
contact your dealer.
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 or above
the indicated mark, 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.2.0L L4 Engine and 3.6L
V6 Engine
Automatic Coolant Service
Fill Instructions
The vehicle is equipped with a
service feature that assists
with filling and removing air
from the cooling system after
service of components or
when coolant is added after
being to low.