2021 CADILLAC CT4 oil

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
VEHICLE CARE 313
explanation of what kind of oil to use.
For engine oil crankcase capacity, see
Capacities and Specifications0396.
Caution
Do not add too much oil. Oil levels
above or below the acceptable
operating range shown on the
dipstick are harmful to the engine.
If the oil level is above the
operating range (i.e., the engine has
so much oil that the oil level gets
above the cross-hatched area that
shows the proper operating range),
the engine could be damaged. Drain
the excess oil or limit driving of the
vehicle, and seek a service
professional to remove the
excess oil.
See Engine Compartment Overview
0 309 for the location of the engine oil
fill cap.
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 Lubricants 0391.
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 engine, 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.

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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. 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 servicepeople 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) 0107 or
Driver Information Center (DIC)
(Uplevel) 0110.
2. Press and hold the thumbwheel on the steering wheel. When the
confirmation message displays,
select YES. The oil life will change
to 100%.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
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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) 0107 or
Driver Information Center (DIC)
(Uplevel) 0110.
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 (Continued)
Caution (Continued)
transmission fluid. See
Recommended Fluids and Lubricants
0391.
Change the fluid and filter at the
intervals listed in Maintenance
Schedule 0380, and be sure to use the
fluid listed in Recommended Fluids and
Lubricants 0391.
Engine Air Filter Life
System
If equipped, 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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
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2.7L L4 Engine
1. Engine Coolant Surge Tank andPressure Cap
2. Engine Cooling Fan (Out of View)
3. Cooling System Air Bleeder Cap
{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 0380 and
Recommended Fluids and Lubricants
0 391.
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 0322.
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.
.Helps keep the proper engine
temperature.

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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.
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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
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334 VEHICLE CARE
FusesUsage
26 Engine control module
27 Injectors/Ignition 2
28 Charged air cooler
29 Transmission aux oil pump/Transmission
reverse lock out
30 Injectors/Ignition 1
31 Emissions 1
32 Emissions 2
33 Starter solenoid
34 –
35 –
36 Starter pinion
37 AC clutch
38 –
39 –
40 –
41 –
42 Water pump
43 – Fuses
Usage
44 –
Relays Usage
47 –
48 Front wiper speed
49 Front wiper control
51 –
52 Engine control module
53 Starter solenoid
54 Starter pinion
55 –
57 AC clutch
58 –Instrument Panel Fuse
Block
The instrument panel fuse block is in
the end of the driver side of the
instrument panel.
To access the fuses, remove the end
panel by gently prying with a plastic
tool near each clip, beginning at the
point shown.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
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to carry. The speed rating is the
maximum speed a tire is certified
to carry a load.
Tire Terminology and
Definitions
Air Pressure:The amount of air
inside the tire pressing outward
on each square inch of the tire.
Air pressure is expressed in kPa
(kilopascal) or psi (pounds per
square inch).
Accessory Weight
:The combined
weight of optional accessories.
Some examples of optional
accessories are automatic
transmission, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of
a tire's height to its width.
Belt
:A rubber coated layer of
cords between the plies and the
tread. Cords may be made from
steel or other reinforcing
materials. Bead
:The tire bead contains steel
wires wrapped by steel cords that
hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in
which the plies are laid at
alternate angles less than
90 degrees to the centerline of the
tread.
Cold Tire Pressure
:The amount
of air pressure in a tire, measured
in kPa (kilopascal) or psi (pounds
per square inch) before a tire has
built up heat from driving. See
Tire Pressure 0346.
Curb Weight
:The weight of a
motor vehicle with standard and
optional equipment including the
maximum capacity of fuel, oil, and
coolant, but without passengers
and cargo.
DOT Markings
:A code molded
into the sidewall of a tire
signifying that the tire is in
compliance with the U.S.
Department of Transportation
(DOT) Motor Vehicle Safety Standards. The DOT code includes
the Tire Identification Number
(TIN), an alphanumeric designator
which can also identify the tire
manufacturer, production plant,
brand, and date of production.
GVWR
:Gross Vehicle Weight
Rating. See Vehicle Load Limits
0 214.
GAWR FRT
:Gross Axle Weight
Rating for the front axle. See
Vehicle Load Limits 0214.
GAWR RR
:Gross Axle Weight
Rating for the rear axle. See
Vehicle Load Limits 0214.
Intended Outboard Sidewall
:
The side of an asymmetrical tire
that must always face outward
when mounted on a vehicle.
Kilopascal (kPa)
:The metric unit
for air pressure.
Light Truck (LT-Metric) Tire
:A
tire used on light duty trucks and
some multipurpose passenger
vehicles.

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Remove any accessories that may be
damaged or interfere with the car
wash equipment.
Rinse the vehicle well, before washing
and after, 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
e
symbol.
This could cause damage that
would not be covered by the vehicle
warranty.
Solvents or aggressive cleaners may
harm underhood components. The
usages of these chemicals should be
avoided.
Recommend water only. A pressure washer may be used, but
care must be utilized. The following
criteria must be followed:
.Water pressure must be kept below
14 000 KPa (2,000 PSI).
.Water temperature must be below
80 °C (180 °F).
.Spray nozzle with a 40 degree wide
angle spray pattern or wider must
be used.
.Nozzle 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. Foreign
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's 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.
Do not apply waxes or polishes to
uncoated plastic, vinyl, rubber, decals,
simulated wood, or flat paint as
damage can occur.
Caution
Machine compounding or
aggressive polishing on a basecoat/
clearcoat paint finish may damage
it. Use only non-abrasive waxes and
polishes that are made for a
basecoat/clearcoat paint finish on
the vehicle.
To keep the paint finish looking new,
keep the vehicle garaged or covered
whenever possible.