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Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 299
Keep a record with all parts receipts
and list the mileage and the date of
any service work performed. See
Maintenance Records0402.
Caution
Even small amounts of
contamination can cause damage to
vehicle systems. Do not allow
contaminants to contact the fluids,
reservoir caps, or dipsticks.
Hood
{Warning
Gas struts and other metal
components under the hood can get
hot after running the engine. Do
not touch these components as
they can burn unprotected skin and
could cause serious injury.
Clear any snow from the hood before
opening. To open the hood:
1. Pull the hood release handle. It is
on the lower left side of the
instrument panel between the
door and the steering wheel.
2. Release the handle, then pull the handle again to fully open
the hood.
3. Go to the front of the vehicle and lift the hood open.
Caution
Be sure the hood is completely
closed before driving. Damage may
occur if it is not. To close the hood:
1. Before closing the hood, be sure all filler caps are properly
installed.
2. Lower the hood approximately 46 cm (18 in) from the closed
position.
3. Then push the front center of the hood with a swift, firm motion.
4. Check to make sure the hood is closed. If not, release the hood
from inside and repeat Steps 1–3.
Page 301 of 445
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
300 VEHICLE CARE
Engine Compartment Overview
2.0L L4 Gasoline Only Engine
Page 302 of 445
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 301
1. Engine Coolant Surge Tank andPressure Cap.
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
2. Engine Air Cleaner/Filter 0311.
3. Engine Oil Fill Cap. See Engine Oil
0 307.
4. Engine Cooling Fan (Out of View).
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
5. Engine Oil Dipstick. See Engine
Oil 0307.
6. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0374.
7. Engine Compartment Fuse Block
0332.
8. Brake Fluid Reservoir (Under Cover). See Brake Fluid0323.
9. Windshield Washer Fluid Reservoir. See Washer Fluid
0 322. 10. Remote Negative (-) Battery
Terminal. See Jump Starting -
North America 0374.
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Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 303
1. Engine Coolant Surge Tank andPressure Cap.
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
2. Traction Power Inverter Module (TPIM).
3. High Voltage DC Cables.
4. TPIM Coolant Reservoir and Pressure Cap.
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
5. High Voltage AC Cables.
6. Engine Air Cleaner/Filter 0311.
7. Engine Oil Fill Cap. See Engine Oil
0 307.
8. Engine Cooling Fan (Out of View).
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
9. Engine Oil Dipstick. See Engine
Oil 0307.
10. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0374. 11.
Engine Compartment Fuse Block
0332.
12. Brake Fluid Reservoir (Under Cover). See Brake Fluid0323.
13. Windshield Washer Fluid Reservoir. See Washer Fluid
0 322.
14. Remote Negative (-) Battery Terminal. See Jump Starting -
North America 0374.
Page 306 of 445
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 305
1. Engine Coolant Surge Tank andPressure Cap.
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
2. Engine Air Cleaner/Filter 0311.
3. Engine Cooling Fan (Out of View).
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
4. Engine Oil Fill Cap. See Engine Oil
0 307.
5. Engine Oil Dipstick. See Engine
Oil 0307.
6. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0374.
7. Engine Compartment Fuse Block
0332.
8. Brake Fluid Reservoir. See Brake
Fluid 0323.
9. Windshield Washer Fluid Reservoir. See Washer Fluid
0 322. 10. Remote Negative (-) Battery
Terminal. See Jump Starting -
North America 0374.
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Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 307
1. Engine Coolant Surge Tank andPressure Cap.
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
2. Engine Air Cleaner/Filter 0311.
3. Engine Cooling Fan (Out of View).
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
4. Engine Oil Fill Cap. See Engine Oil
0 307.
5. Engine Oil Dipstick. See Engine
Oil 0307.
6. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0374.
7. Engine Compartment Fuse Block
0332.
8. Brake Fluid Reservoir. See Brake
Fluid 0323.
9. Windshield Washer Fluid Reservoir. See Washer Fluid
0 322. 10. Remote Negative (-) Battery
Terminal. See Jump Starting -
North America 0374.
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” later in
this section.
. Change the engine oil at the
appropriate time. See Engine Oil
Life System 0309.
. 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 Overview 0300 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.
Follow these guidelines:
. To get an accurate reading, park
the vehicle on level ground. Check
the engine oil level after the
engine has been off for at least
two hours. Checking the engine oil
level on steep grades or too soon
after engine shutoff can result in
incorrect readings. Accuracy
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Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
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VEHICLE CARE 311
Change the fluid and filter at the
intervals listed inMaintenance
Schedule 0390, and be sure to use the
fluid listed in Recommended Fluids and
Lubricants 0399.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the
engine compartment. See Engine
Compartment Overview 0300.
When to Inspect the Engine Air
Cleaner/Filter
For intervals on changing and
inspecting the engine air cleaner/filter,
see Maintenance Schedule 0390.
How to Inspect 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. Remove the
engine air cleaner/filter. Lightly tap
and shake the engine air cleaner/filter
(away from the vehicle), to release
loose dust and dirt. Inspect the engine air cleaner/filter for damage, and
replace if damaged. Do not clean the
engine air cleaner/filter or
components with water or
compressed air.
To inspect or replace the engine air
cleaner/filter:2.0L L4 Gasoline Only Engine Shown,
2.0L L4 PLUG-IN Engine Similar
1. Remove the five screws on top of the engine air cleaner/filter cover.
2. Lift the engine air cleaner/filter cover open on the hinge.
3. Lift and remove the engine air cleaner/filter. 4. Inspect or replace the engine air
cleaner/filter.
5. Reverse Steps 1–3 to reinstall the engine air cleaner/filter cover.
3.0L V6 Engine
1. Remove the 10 screws on top of the engine air cleaner/filter cover
to gain access to both air
cleaner/filters.
2. Lift the engine air cleaner/filter cover open on the hinge.
3. Lift and remove one or both engine air cleaner/filters.
4. Inspect or replace one or both engine air cleaner/filters.
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Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
312 VEHICLE CARE
5. Reverse Steps 1–3 to reinstall theengine air cleaner/filter cover.
3.6L V6 Engine
1. Screws (6)
2. Bolts (3)
3. Diagonal Brace
1. Remove the three bolts (2) andthe diagonal brace (3).
2. Remove the six screws (1) on top of the engine air cleaner/filter
cover.
3. Lift the engine air cleaner/filter cover open on the hinge.
4. Lift and remove the engine air cleaner/filter. 5. Inspect or replace the engine air
cleaner/filter.
6. Reverse Steps 1–4 to reinstall the engine air cleaner/filter cover
and diagonal brace.
{Warning
Operating the engine with the air
cleaner/filter off can cause you or
others to be burned. The air cleaner
not only cleans the air; it helps to
stop flames if the engine backfires.
Use caution when working on the
engine and do not drive with the air
cleaner/filter off.
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.
Cooling System
(Gasoline Only)
The cooling system allows the engine
to maintain the correct working
temperature.
2.0L L4 Gasoline Only Engine
1. Engine Coolant Surge Tank
and Pressure Cap
2. Engine Cooling Fan (Out of View)