2020 CADILLAC CT6 check oil

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
280 VEHICLE CARE
Engine Oil Additives/Engine Oil
Flushes
Do not add anything to the oil. The
recommended oils meeting the dexos
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
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. Neverdispose 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 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) 0132.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
VEHICLE CARE 281
2. Press and hold SEL to clear theCHANGE ENGINE OIL SOON
message and reset the oil life
at 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) 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
0
368.
Change the fluid and filter at the
intervals listed in Maintenance
Schedule 0359, and be sure to use the
fluid listed in Recommended Fluids and
Lubricants 0368.
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.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
282 VEHICLE CARE
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 Engine Air Filter
Life System
Reset the system whenever the engine
air filter is replaced so that the system
can calculate the next engine air filter
change.To reset:
1. Place the vehicle in P (Park).
2. Display the Air Filter Life on the DIC. See Driver Information Center
(DIC) 0132.
3. Press
Ton the steering wheel to
move to the Reset/Disable
display area. Select Reset, then
press SEL.
4. Press SEL to confirm the reset.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the
engine compartment. See Engine
Compartment Overview 0274.
When to Inspect the Engine Air
Cleaner/Filter
.
For intervals on changing and
inspecting the engine air cleaner/
filter, see Maintenance Schedule
0 359.
. If equipped with Engine Air Filter
Life System, see Engine Air Filter
Life System 0281.
. If driving in very dusty areas,
follow the engine air filter
inspecting and changing intervals,
see Maintenance Schedule 0359.
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.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
VEHICLE CARE 285
4.2L V8 Engine
1. Engine Coolant Surge Tankand Pressure Cap (Under
Cover)
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. If the coolant inside the coolant surge
tank is boiling, do not do anything
else until it cools down. The vehicle
should be parked on a level surface.
The coolant level should be at the
indicated mark on the middle of the
tank. If it is not, the vehicle may have
a leak at the radiator hoses, heater
hoses, radiator, water pump,
or somewhere else in the cooling
system.
{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.
If there seems to be no leak, with the
engine on, check to see if the electric
cooling fan is running. If the engine is
overheating, the fan should be
running. If it is not, the vehicle needs
service. Turn off the engine.
Engine Coolant
The engine cooling system in the
vehicle is filled with a DEX-COOL
engine coolant mixture. This coolant
needs to be checked and replaced at
appropriate intervals. See Maintenance
Schedule 0359.
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 0288.
What to Use
{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 CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
286 VEHICLE CARE
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. If using this mixture, nothing
else needs to be added. 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.
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.
3.6L V6 and 4.2L V8 Engine Coolant
Surge Tank The coolant surge tank is in the
engine compartment on the passenger
side of the vehicle. See
Engine
Compartment Overview 0274.
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. See Engine Overheating
0 288.
How to Add Coolant to the
Coolant Surge Tank
If no problem is found, check to see if
coolant is visible in the coolant surge
tank. If coolant is visible but 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, including the
coolant surge tank pressure cap, is
cool before this is done. See Engine
Overheating 0288.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
SERVICE AND MAINTENANCE 357
Service and
Maintenance
General Information
General Information . . . . . . . . . . . . . 357
Maintenance Schedule
Maintenance Schedule . . . . . . . . . . . 359
Special Application Services
Special Application Services . . . . . 364
Additional Maintenance
and Care
Additional Maintenanceand Care . . . . . . . . . . . . . . . . . . . . . . . . . 365
Recommended Fluids,
Lubricants, and Parts
Recommended Fluids andLubricants . . . . . . . . . . . . . . . . . . . . . . . 368
Maintenance Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369
Maintenance Records
Maintenance Records . . . . . . . . . . . . 371
General Information
Your vehicle is an important
investment. This section describes the
required maintenance for the vehicle.
Follow this schedule to help protect
against major repair expenses
resulting from neglect or inadequate
maintenance. It may also help to
maintain the value of the vehicle if it
is sold. It is the responsibility of the
owner to have all required
maintenance performed.
Your dealer has trained technicians
who can perform required
maintenance using genuine
replacement parts. They have
up-to-date tools and equipment for
fast and accurate diagnostics. Many
dealers have extended evening and
Saturday hours, courtesy
transportation, and online scheduling
to assist with service needs.
Your dealer recognizes the importance
of providing competitively priced
maintenance and repair services. With
trained technicians, the dealer is the place for routine maintenance such as
oil changes and tire rotations and
additional maintenance items like
tires, brakes, batteries, and wiper
blades.
Caution
Damage caused by improper
maintenance can lead to costly
repairs and may not be covered by
the vehicle warranty. Maintenance
intervals, checks, inspections,
recommended fluids, and lubricants
are important to keep the vehicle in
good working condition.
Do not have chemical flushes that
are not approved by GM performed
on the vehicle. The use of flushes,
solvents, cleaners, or lubricants that
are not approved by GM could
damage the vehicle, requiring
expensive repairs that are not
covered by the vehicle warranty.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
SERVICE AND MAINTENANCE 359
Maintenance Schedule
Owner Checks and Services
Check the engine oil level. SeeEngine
Oil 0277.
Once a Month
. Check the tire inflation pressures.
See Tire Pressure 0322.
. Inspect the tires for wear. See Tire
Inspection 0329.
. Check the windshield washer fluid
level. See Washer Fluid 0289.
Engine Oil Change
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
0280.
Engine Air Filter Change
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 0281.
Air Conditioning Desiccant
(Replace 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.
Tire Rotation and Required
Services Every 12 000 km
(7,500 mi)
Rotate the tires, if recommended for
the vehicle, and perform the following
services. See Tire Rotation0329.
. Check engine oil level and oil
life percentage. If needed,
change engine oil and filter,
and reset oil life system. See
Engine Oil 0277 and
Engine Oil Life System 0280.
. If equipped with the engine air
filter life system, check the air
filter life percentage. If necessary,
replace the engine air filter and
reset the engine air filter life
system. See Engine Air Filter Life
System 0281. If the vehicle is not
equipped with the engine air filter
life system, inspect the engine air
cleaner filter. See Engine Air
Cleaner/Filter 0282.
. Check engine coolant level. See
Cooling System 0284.
. Check windshield washer fluid
level. See Washer Fluid 0289.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
SERVICE AND MAINTENANCE 361
Maintenance Schedule
Additional Required Services -
Normal12 000 km/7,500 mi
24 000 km/15,000 mi
36 000 km/22,500 mi
48 000 km/30,000 mi
60 000 km/37,500 mi
72 000 km/45,000 mi
84 000 km/52,500 mi
96 000 km/60,000 mi
108 000 km/67,500 mi
120 000 km/75,000 mi
132 000 km/82,500 mi
144 000 km/90,000 mi
156 000 km/97,500 mi
168 000 km/105,000 mi
180 000 km/112,500 mi
192 000 km/120,000 mi
204 000 km/127,500 mi
216 000 km/135,000 mi
228 000 km/142,500 mi
240 000 km/150,000 mi
Rotate tires, if recommended for the vehicle, and
perform Required Services. (1) Check engine oil level
and oil life percentage. Change engine oil and filter,
if needed. Check engine air filter life percentage and
status. Change engine air filter, if needed.
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
Replace passenger compartment air filter. (2)@ @@@@@
Inspect evaporative control system. (3)@ @@
Replace spark plugs. Inspect spark plug wires and/or
boots. (4.2L Engine)@ @
Replace spark plugs. Inspect spark plug wires and/or
boots. (3.6L Engine)@
Change transfer case fluid. (4)@
Change rear axle fluid. (Except V-Series) (4)@
Change rear axle fluid. (V-Series Only) (4)@@@
Change front axle fluid 4WD. (4)@
Drain and fill engine cooling system. (5)@
Visually inspect accessory drive belts. (6)@
Replace brake fluid. (7)
Replace windshield wiper blades. (8)
@ @ @ @ @ @ @ @ @ @
Replace hood and/or body lift support gas struts. (9)@ @
Replace air conditioning desiccant. (10)