2023 CADILLAC CT4 engine oil

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
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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
408 Vehicle Care
Fuses Usage
1 Long Range RadarFront Sensor
2 Park/Daytime Running Lamps
3 Exterior Lighting Module 4
4 Exterior Lighting Module 7
5 Headlamp Level
6 –
Fuses Usage
7 Electronic Brake
Control Module
8 Washer Pump
9 –
10 –
11 –
12 Horn
13 Front Wiper
Fuses Usage
14 Exterior Lighting Module 6
15 Exterior Lighting Module 1
16 Exterior Lighting Module 5
17 Exterior Lighting Module 3
18 Aero Shutter
19 –
20 –
21 Virtual Key System/ Power Sounder
Module
22 Engine Control Module Battery
23 Transmission Control Module
24 Active Engine Mount
25 –
26 Engine Control Module
27 Injectors/Ignition 2
28 Charged Air Cooler/ Not Used
29 Transmission Aux Oil Pump/Transmission
Reverse Lock Out

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
472 Service and Maintenance
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.
Every 120 000 km
(75,000 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.
Owner Checks and
Services
Every Five Years
.Replace brake fluid every
five years. See Brake Fluid
0
398.
Every Seven Years
.Replace Air Conditioning
Desiccant every seven years.
The air conditioning system
requires maintenance every
seven years. This service
requires replacement of the
desiccant to help the
longevity and efficient
operation of the air
conditioning system. This
service can be complex. See
your dealer.
Multi-Point Vehicle
Inspection (MPVI)
A Multi Point Vehicle
Inspection (MPVI) completed
by a GM dealer technician is a
maintenance assessment of
your vehicle. The benefit of
the MPVI is to identify and
inform the customer of service
items that require immediate
attention and those that may
require attention in the future.
The technician will perform the
following checks on your
vehicle. For a complete list of
checks, inspections, and
services, see your dealer.
Some items may not apply to
your vehicle and/or region.
Diagnostics
.OnStar active, if equipped
.Service history/recall check
Engine Oil and Filter
.Engine oil
.Oil life monitor
‐ Reset oil life monitor

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Service and Maintenance 473
Exterior Lights
.Visual inspection
Windshield and Wipers
.Visual inspection
Battery
.Battery visual inspection
.Battery test results
.Battery cables and
connections
Systems, Fluids, and
Visible Leak Inspection
.Engine oil
.Transmission
.Drive axle
.Transfer case
.Engine cooling system
.Power steering, if equipped
.Fuel system
.Windshield washer fluid
Tire Inspection
.Tire pressure, tread depth,
and wear
.Rotation, if applicable
.Alignment check, optional
.Reset tire pressure monitor
.Check tire sealant expiration
date, if equipped
.Check spare tire, if equipped
Brakes
.Check brake system
Visible and Functional
Inspections
.Seat belt components
.Exhaust system
.Accelerator pedal
.Passenger compartment air
filter, if equipped
.Engine air filter
.Hoses
.Belts
.Shocks and struts
.Steering components
.Axle boots or driveshaft and
u-joints
.Compartment lift struts,
if equipped
.Floor mats secured, no
interference with pedals
.Horn
.Ignition lock, if equipped
.Starter switch
.Evaporative control system
Lubricate
.Chassis components
Special Application
Services
.Severe Commercial Use
Vehicles Only: Lubricate
chassis components every
oil change.
.Have underbody flushing
service performed. See
"Underbody Maintenance" in
Exterior Care 0455.