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
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
456 Vehicle Care
Remove any accessories that
may be damaged or interfere
with the car wash equipment.
Hand Wash
Rinse the vehicle well, before
and after washing, to remove
all cleaning agents completely.
If they are allowed to dry on
the surface, they could stain.
Dry the finish with a soft, clean
chamois or an all-cotton towel
to avoid surface scratches
and water spotting.
Cleaning Underhood
Components
Caution
Do not power wash any
component under the hood
that has this
esymbol.
This could cause damage to
the vehicle that would not
be covered by the vehicle
warranty. Avoid using solvents or
abrasive cleaners that may
harm underhood components.
GM recommends using only
water to clean underhood
components.
If using a pressure washer,
ensure the following criteria
is met:
.Water pressure must be
kept below 14 000 KPa
(2,000 PSI).
.Water temperature must be
below 80 °C (180 °F).
.A spray nozzle with a
40 degree wide angle spray
pattern or wider must be
used, and must be kept at
least 30 cm (1 ft) away from
all surfaces.
Finish Care
Application of aftermarket
clearcoat sealant/wax
materials is not recommended.
If painted surfaces are
damaged, see your dealer to
have the damage assessed
and repaired. Materials such as calcium chloride and other
salts, ice melting agents, road
oil and tar, tree sap, bird
droppings, chemicals from
industrial chimneys, etc., can
damage the vehicle finish if
they remain on painted
surfaces. Wash the vehicle as
soon as possible. If necessary,
use non-abrasive cleaners that
are marked safe for painted
surfaces to remove foreign
matter.
Occasional hand waxing or
mild polishing should be done
to remove residue from the
paint finish. See your dealer
for approved cleaning
products.
Caution
Do not apply waxes or
polishes to uncoated plastic,
vinyl, rubber, decals,
simulated wood, or matte
paint as damage can occur.
Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 461
Interior Care
To prevent dirt particle
abrasions, regularly clean the
vehicle's interior. Before using
cleaners, read and follow all
safety instructions on the
label. While cleaning the
interior, open the doors and
windows to get proper
ventilation. Newspapers or
dark garments can transfer
color to the vehicle’s interior.
Caution
Immediately remove
cleaners, hand lotions,
sunscreen, and insect
repellent from all interior
surfaces or permanent
damage may result.
Caution
Use cleaners specifically
designed for the surfaces
being cleaned to prevent
permanent damage to the(Continued)
Caution (Continued)
vehicle. Apply all cleaners
directly to a cleaning cloth.
Do not spray cleaners on
any switches or controls.
When using liquid soap
cleaners, follow the directions
on the specific cleaner or soap
solution for dilution
instructions.
Caution
To prevent damage:
.Never use a razor or any
other sharp object to
remove soil from any
interior surface
.Never use a brush with
stiff bristles.
.Never rub any surface
aggressively or with too
much pressure.
.Do not get any exposed
electrical components wet. (Continued)
Caution (Continued)
.Do not use laundry
detergents or dishwashing
soaps with degreasers. Do
not use solutions that
contain strong or
caustic soap.
.Do not heavily saturate
the upholstery when
cleaning.
.Do not use solvents or
cleaners containing
solvents.
.Do not use disinfecting
wipes that are scented or
contain bleach. Do not use
wipes or cleaners that
show a color transfer to
the wipe or change the
appearance of the interior
surface when used.
.Do not use scented or
gel-type hand sanitizers.
If hand sanitizer comes in
contact with interior
surfaces of the vehicle,
blot immediately and clean(Continued)
Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Service and Maintenance 471
Severe Conditions
Requiring More Frequent
Maintenance*
.Public service, military,
or commercial use vehicles
to include the following:
‐Ambulances, police cars,
and emergency rescue
vehicles.
‐ Civilian vehicles such as
light duty pick-up trucks,
SUVs, and passenger cars
that are used in military
applications.
‐ Recovery vehicles such as
tow trucks and flatbed
single vehicle carriers or
any vehicle that is
consistently used in towing
trailers or other loads.
‐ High use commercial
vehicles such as courier
delivery vehicles, private
security patrol vehicles,
or any vehicles that
operate on a 24–hour
basis. ‐
Any vehicle consistently
operated in a high sand or
dust environment such as
those used on oil pipelines
and similar applications.
.Vehicles that are regularly
used for short trips of 6 km
(4 mi) or less.
The oil life indicator will show
you when to change the oil
and filter. Under severe
conditions the indicator may
come on before 12 000 km
(7,500 mi).
* Footnote: Under extreme
driving conditions listed
above, it may be necessary
to replace your spark plugs
at more frequent intervals.
For further assistance in
determining the most
suitable service maintenance
intervals for your vehicle,
please contact your
authorized GM Dealer. Extreme service is for
vehicles mainly driven
off-road in four-wheel drive
or used in farming, mining,
forestry, or snow plowing.Additional Required
Services
—Severe Service
Every 72 000 km (45,000 mi)
.Change automatic
transmission fluid and filter.
.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.
.Change rear axle fluid, with
limited slip differential. Do
not directly power wash the
transfer case and/or front/
rear axle output seals. High
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
508 Connected Services
vehicles, Wi-Fi can also be
managed from the Wi-Fi
Hotspot menu.
MyCadillac Mobile App (If
Available)
Download the myCadillac
mobile app to compatible
Apple and Android
smartphones. Cadillac users
can access the following
services from a smartphone:
.Remotely start/stop the
vehicle, if factory-equipped.
.Lock/unlock doors,
if equipped with automatic
locks.
.Activate the horn and lamps.
.Check the vehicle fuel level,
oil life, or tire pressure,
if factory-equipped with the
Tire Pressure Monitor
System.
.Send destinations to the
vehicle.
.Locate the vehicle on a map
(U.S. market only).
.Turn the vehicle's Wi-Fi
hotspot on/off, manage
settings, and monitor data
consumption, if equipped.
.Locate a dealer and
schedule service.
.Request Roadside
Assistance.
.Set a parking reminder with
pin drop, take a photo, make
a note, and set a timer.
.Connect with Cadillac on
social media.
Features are subject to
change. For myCadillac mobile
app information and
compatibility, see
my.cadillac.com.
An active OnStar or
connected service plan may be
required. A compatible device,
factory-installed remote start,
and power locks are required.
Data rates apply. See
www.onstar.com for details
and system limitations.
Remote Services
Contact an OnStar Advisor to
unlock the doors or sound the
horn and flash the lamps.
Marketplace
OnStar Advisors can provide
offers from restaurants and
retailers on your route, help
locate hotels, or book a room.
These services vary by
market.
Diagnostics
By monitoring and reporting
on the vehicle’s key systems,
OnStar Advanced Diagnostics,
if equipped, provides a way to
keep up on maintenance.
Capabilities vary by model. See
www.onstar.com for details
and system limitations.
Features are subject to
change. For updates on
feature capabilities, see
my.cadillac.com. Message and
data rates may apply.
Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/10/22
516 INDEX
LATCH, Lower Anchorsand Tethers for
Children . . . . . . . . . . . . . . . . . . . . . . . . . 80
LED Lighting . . . . . . . . . . . . . . . . . . 403
Lighting Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
Illumination Control . . . . . . . . 150
LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403
Lights Airbag Readiness . . . . . . . . . . . 116
Antilock Brake System
(ABS) Warning . . . . . . . . . . . . . . 121
Automatic Emergency Braking (AEB)
Disabled . . . . . . . . . . . . . . . . . . . . . 123
Automatic Vehicle Hold . . . . . . . . . . . . . . . . 122
Brake System Warning . . . . . . . . . . . . . . . . . . . . . 120
Charging System . . . . . . . . . . . . 117
Check Engine
(Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . 118
Cruise Control Light . . . . . . . 128
Door Ajar . . . . . . . . . . . . . . . . . . . . . . 129
Driver Mode Control . . . . . . . 125
Electric Parking Brake . . . . . 121 Lights (cont'd)
Engine Coolant
Temperature
Warning . . . . . . . . . . . . . . . . . . . . . 124
Engine Oil Pressure . . . . . . . . 127
Gauges and Indicators . . . . 105
High-Beam On . . . . . . . . . . . . . . . 128
Lane Keep Assist . . . . . . . . . . . 122
Low Fuel Warning . . . . . . . . . . 127
Performance Shifting . . . . . 122
Seat Belt Reminders . . . . . . 115
Security . . . . . . . . . . . . . . . . . . . . . . . 128
Service Electric Parking Brake . . . . . . . . . . . . . . . 121
StabiliTrak OFF . . . . . . . . . . . . . 124
Tire Pressure . . . . . . . . . . . . . . . . 126
Traction Control System
(TCS)/StabiliTrak . . . . . . . . . . 124
Traction Off . . . . . . . . . . . . . . . . . . 123
Limited-Slip Differential . . . . 301
Locks
Automatic Door . . . . . . . . . . . . . . . 21
Delayed Locking . . . . . . . . . . . . . 20
Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Lockout Protection . . . . . . . . . . 21
Power Door . . . . . . . . . . . . . . . . . . . 20
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Loss of Control . . . . . . . . . . . . . . .237
Low Fuel Warning Light . . . . 127
Low-Profile Tires . . . . . . . . . . . . . 416
Lower Anchors and
Tethers for Children
(LATCH System) . . . . . . . . . . . . . 80
Lumbar Adjustment . . . . . . . . . . 40
Front Seats . . . . . . . . . . . . . . . . . . . 40
M
MaintenanceRecords . . . . . . . . . . . . . . . . . . . . . . . 477
Maintenance Schedule . . . . 469 Recommended Fluidsand Lubricants . . . . . . . . . . . 474
Malfunction Indicator Lamp . . . . . . . . . . . . . . .118
Manual Mode . . . . . . . . . . . . . . . . . . . . 280, 281
Transmission . . . . . . . . . . . . . . . 283
Transmission Fluid . . . . . . . . 382
Map Data Updates . . . . . . . . . . . 184
Maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
Massage Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Matching
Active Rev . . . . . . . . . . . . . . . . . . . 285