2023 CADILLAC CT4 air filter

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
378 Vehicle Care
1. Windshield Washer FluidReservoir. See Washer
Fluid 0393.
2. Engine Coolant Surge Tank and Pressure Cap. See
Cooling System 0386.
3. Engine Air Cleaner/Filter 0384.
4. Engine Cooling Fan (Out of View). See Cooling System
0386.
5. Engine Oil Fill Cap. See Engine Oil 0378.
6. Engine Oil Dipstick. See Engine Oil 0378.
7. Remote Positive (+) Battery Terminal. See
Jump Starting - North
America 0447.
8. Brake/Clutch Fluid Reservoir. See Brake Fluid
0398.
9. Remote Negative (-) Battery Terminal. See
Jump Starting - North
America 0447. 10. Engine Compartment Fuse
Block. See Engine
Compartment Fuse Block
0407.
Engine Oil
To ensure proper engine
performance and long life,
careful attention must be paid
to engine oil. Following these
simple, but important steps
will help protect your
investment:
.Use engine oil approved to
the proper specification and
of the proper viscosity
grade. See “Selecting the
Right Engine Oil” in this
section.
.Check the engine oil level
regularly and maintain the
proper oil level. See
“Checking Engine Oil” and
“When to Add Engine Oil” in
this section.
.Change the engine oil at the
appropriate time. See Engine
Oil Life System 0381.
.Always dispose of engine oil
properly. See “What to Do
with Used Oil” in this section.
Checking Engine Oil
Check the engine oil level
regularly, every 650 km
(400 mi), especially prior to a
long trip. The engine oil
dipstick handle is a loop. See
Engine Compartment
Overview0373 for the
location.
{Warning
The engine oil dipstick
handle may be hot; it could
burn you. Use a towel or
glove to touch the dipstick
handle.
If a low oil Driver Information
Center (DIC) message displays,
check the oil level.

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

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
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
Service and Maintenance 469
Maintenance
Schedule
Tire Rotation and
Required Services Every
12 000 km (7,500 mi)
Tires are rotated to achieve a
more uniform wear for all tires.
The first rotation is the most
important.
Anytime unusual wear is
noticed, rotate the tires as
soon as possible, check for
proper tire inflation pressure,
and check for damaged tires
or wheels. If the unusual wear
continues after the rotation,
check the wheel alignment.
See When It Is Time for New
Tires0431 and
Wheel Replacement 0436.
.Perform Multi-Point Vehicle
Inspection. See Multi-Point
Vehicle Inspection (MPVI)
0472.
.Lubricate body components.
See Exterior Care 0455.
Additional Required
Services —Normal
Service
Every 12 000 km (7,500 mi)
.Check engine oil level and oil
life percentage. If needed,
change engine oil and filter,
and reset oil life system. Or
when the CHANGE ENGINE
OIL SOON message displays,
have the engine oil and filter
changed within the next
1 000 km/600 mi. If driven
under the best conditions,
the engine oil life system
may not indicate the need
for vehicle service for up to
a year. The engine oil and
filter must be changed at
least once a year and the oil
life system must be reset.
Your trained dealer
technician can perform this
work. If the engine oil life
system is reset accidentally,
service the vehicle within
5 000 km/3,000 mi since the
last service. Reset the oil life system when the oil is
changed. See Engine Oil Life
System
0381.
.When the REPLACE AT
NEXT OIL CHANGE
message displays, the engine
air filter should be replaced
at the next engine oil
change. When the REPLACE
ENGINE AIR FILTER SOON
message displays, the engine
air filter should be replaced
at the earliest convenience.
Reset the engine air filter life
system after the engine air
filter is replaced. See Engine
Air Filter Life System 0383.
Every 36 000 km (22,500 mi)
.Passenger compartment air
filter replacement (or every
24 months, whichever
occurs first). More frequent
replacement may be needed
if the vehicle is driven in
areas with heavy traffic,
poor air quality, areas with
high dust levels or are
sensitive to environmental
allergens. Filter replacement

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
470 Service and Maintenance
may also be needed if you
notice reduced airflow,
windows fogging up,
or odors. Your local GM
Service location can help you
determine when it is the
right time to replace your
filter.
Every 72 000 km (45,000 mi)
.Change rear axle fluid,
if equipped with limited slip
differential. Do not directly
power wash the transfer
case and/or front/rear axle
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/or axles
and should be replaced.
Every 96 000 km (60,000 mi)
.Replace spark plugs. Inspect
spark plug wires and/or
boots. Every 156 000 km
(97,500 mi)
.Change transfer case fluid,
if equipped with AWD. Do
not directly power wash the
transfer case and/or front/
rear axle 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/or
axles and should be
replaced.
Every 161 000 km
(100,000 mi)
.Replace hood and/or body
lift support gas struts. Or
every 10 years, whichever
comes first. See Gas Strut(s)
0 402.
Every 240 000 km
(150,000 mi)
.Change rear axle fluid,
without limited slip
differential. Do not directly
power wash the transfer
case and/or front/rear axle 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/or axles
and should be replaced.
.Change front axle fluid,
if equipped with AWD. Do
not directly power wash the
transfer case and/or front/
rear axle 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/or
axles and should be
replaced.
.Drain and fill engine cooling
system. Or every six years,
whichever comes first. See
Cooling System
0386.