engine oil CADILLAC CT4 2021 User Guide

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
208 DRIVING AND OPERATING
Engine Oil
Check the oil level often during track
events and competitive driving and
keep the oil level at or near the
upper mark.
Fuel
Use premium unleaded gasoline with
a posted octane rating of 93 at a track
event. Unleaded gasoline with a
posted octane rating of 91 may be
used, but performance will be
degraded.
Automatic Transmission Fluid
Have the transmission fluid set to the
track specific oil level prior to track
usage. Transmission fluid should be
changed after every 15 hours of track
usage. Any transmission level set or
change should be performed at your
dealer.
Brakes
Brake cooling can be improved if the
front brake disc splash shield and
front tire deflector are removed.
Removing the shield will require that
the suspension bushings and wheelspeed wires visible to the brake disc
be protected with insulated thermal
wrapping.
Caution
Removing the splash shield can
degrade wet braking performance,
as well as introduce brake pedal
pulsation, due to brake disc
exposure to road debris. Only
remove the front brake disc splash
shield and front tire deflector when
driving in track events.
Brake Pad Wear Sensors
(V-Series Only)
If equipped, the brake pad wear
sensors need to be removed from the
brake calipers prior to any track or
racing event. The original sensors can
be reinstalled if significant brake pad
wear is not observed. The sensor
should not extend beyond the brake
pad surface at the rotor contact.
If this condition is observed, the brake
pad life system needs to be disabled
until a new set of brake pads and
sensors are installed and the system
reset. Brake Fluid
.Before racing, replace existing brake
fluid with a qualified racing brake
fluid from a sealed container. Brake
fluid with a dry boiling point
>279 °C (534 °F) is qualified.
If racing brake fluid is used, replace
it with GM approved brake fluid
before driving on public roads. See
Recommended Fluids and Lubricants
0
391.
.Do not use silicone-based fluids.
If racing brake fluid is in the vehicle
and the age of the brake fluid is over a
month old or unknown, replace the
brake fluid between racing/closed
track driving.
Caution
Failure to change the brake fluid
and transfer case fluid after any
performance or race track driving
could result in damage not covered
by the vehicle warranty. Have the
brake fluid and transfer case fluid
changed by your dealer after any (Continued)

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
DRIVING AND OPERATING 209
Caution (Continued)
performance or race track driving.
SeeRecommended Fluids and
Lubricants 0391.
Brake Fade Warning Assist
The Brake Fade Warning Assist
system monitors the performance of
the brake system. If the system
detects brake fade, or if the brake
fluid is near the boiling point, the
driver will be alerted.
The Brake Fade Warning Assist
system is designed for use with the
factory-installed brake pads or
GM-approved replacement pads. If the
brake pads on the vehicle need to be
replaced, use GM-approved brake
pads. If this is not done, the brake
fade warning system may not function
properly.
Stage 1 : The Driver Information
Center (DIC) displays a “Reduce
Braking to Avoid Overheating”
message and brake pedal effort and
travel is increased. When the message
displays, the driver should decrease
brake pedal pressure. Stage 2 :
The Driver Information
Center (DIC) displays a “Brakes
Overheated Service Now ”message that
the brake fluid temperature is
excessive and is about to boil. The
system increases brake pedal effort
and travel, and will also limit vehicle
speed. The driver should immediately
start a cool down lap if on the track.
If this message displays, take the
vehicle to be serviced at your dealer.
Brake Burnishing
For vehicles equipped with front
Brembo brake systems:
Performance/racing brake pads are
required prior to racing or closed track
driving. Vehicles with option code JE2
have performance brake pads.
New brake pads must be burnished
before racing or other competitive
driving.
These procedures are specific to the
V-Series brake package. This
procedure should not be performed on
other models as damage may result.
Caution
Performing the brake burnish
procedure on a base brake system
can result in brake damage.
Caution
The new vehicle break-in period
should be completed before
performing the brake burnish
procedure, otherwise damage may
occur to the powertrain/engine. See
New Vehicle Break-In 0218.
Caution
Brake fade will occur during this
track burnish procedure and can
cause brake pedal travel and force
to increase. This could extend
stopping distance until the brakes
are fully burnished.
When this procedure is performed as
instructed, it will not damage the
brakes. The brake pads will smoke and
produce an odor. The braking force

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
218 DRIVING AND OPERATING
Starting and Operating
New Vehicle Break-In
Follow these recommended guidelines
during the first 2 400 km (1,500 mi) of
driving this vehicle. Parts have a
break-in period and performance will
be better in the long run.
For the first 2 400 km (1,500 mi):
.Avoid full throttle starts and abrupt
stops.
.Do not exceed 4000 engine rpm.
.Avoid driving at any one constant
speed, fast or slow.
.Avoid downshifting to brake or slow
the vehicle when the engine speed
will exceed 4000 rpm.
.Do not let the engine labor. Never
lug the engine in high gear at low
speeds.
.Do not participate in track events,
sport driving schools, or similar
activities during this break-in
period.
.Check engine oil with every
refueling and add if necessary. Oil
and fuel consumption may be
higher than normal during the first
2 400 km (1,500 mi).
.To break in new tires, drive at
moderate speeds and avoid hard
cornering for the first
300 km (200 mi). New tires do not
have maximum traction and may
tend to slip.
.New brake linings also need a
break-in period. Avoid making hard
stops during the first
300 km (200 mi). This is
recommended every time brake
linings are replaced.
Composite Materials
This vehicle may be equipped with
parts containing carbon fiber,
sheet-molding compound, or other
composite materials. Dealer-installed
accessories may also contain
composite materials.
{Warning
Exposed edges of parts containing
carbon fiber and other composite
materials can be sharp. Contact
with these parts could result in
injury. Use caution to avoid
contacting these parts, including
when washing the vehicle. If the
parts are damaged, replace the
parts promptly with replacements
from your dealer.
{Warning
Rocker extensions may break under
pressure, resulting in property
damage or injury. Do not stand on
the rocker extension or use it as
a step.
{Warning
Rear end spoilers may break under
pressure, resulting in property
damage or injury. Do not push the
vehicle by the spoiler or use the
spoiler as a handle.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
DRIVING AND OPERATING 221
If the remote key is not in the
vehicle, if there is interference, or if
the remote key battery is low, a
Driver Information Center (DIC)
message will display. SeeRemote
Keyless Entry (RKE) System
Operation 07.
Caution
Cranking the engine for long
periods of time, by pressing
ENGINE START/STOP immediately
after cranking has ended, can
overheat and damage the cranking
motor, and drain the battery. Wait
at least 15 seconds between each
try, to let the cranking motor
cool down.
2. If the engine does not start after five to 10 seconds, especially in
very cold weather (below −18 °C or
0 °F), it could be flooded with too
much gasoline. Try pushing the
accelerator pedal all the way to the
floor and hold it there, then press
ENGINE START/STOP for up to a
maximum of 15 seconds. Wait at
least 15 seconds between each try,
to allow the cranking motor to cool down. When the engine starts, let
go of the button and the
accelerator. If the vehicle starts
briefly but then stops again, do the
same thing. This clears the extra
gasoline from the engine. Do not
race the engine immediately after
starting it. Operate the engine and
transmission gently until the oil
warms up and lubricates all
moving parts.
Stopping the Engine
Move the shift lever to P (Park) and
press and hold ENGINE START/STOP
on the instrument panel, until the
engine shuts off. If the shift lever is
not in P (Park), the engine shuts off
and the ignition goes to ACC/
ACCESSORY. The DIC displays SHIFT
TO PARK. Once the shift lever is
moved to P (Park), the vehicle
turns off.
If the remote key is not detected
inside the vehicle when it is turned off
the DIC displays a message.
Stop/Start System
The Stop/Start system will shut off
the engine to help conserve fuel.
It has components designed for the
increased number of starts.
{Warning
The automatic engine Stop/Start
feature causes the engine to shut
off while the vehicle is still on. Do
not exit the vehicle before shifting
to P (Park). The vehicle may restart
and move unexpectedly. Always
shift to P (Park), and then turn the
ignition off before exiting the
vehicle.
Auto Engine Stop/Start
When the brakes are applied and the
vehicle is at a complete stop, the
engine may turn off. When stopped,
the tachometer displays AUTO STOP.
See Tachometer 093. When the brake
pedal is released or the accelerator
pedal is pressed, the engine will
restart.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
294 DRIVING AND OPERATING
Recommended Fuel (L3B
2.7L L4 Turbo Engine)
Use premium unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 93—
(R+M)/2. If unavailable, unleaded
gasoline with a posted octane rating
of 91 may be used, but with reduced
performance and fuel economy. If the
octane is less than 91, the engine
could be damaged and the repairs
would not be covered by the vehicle
warranty. If heavy knocking is heard
when using gasoline rated at
93 octane, the engine needs service.
Do not use any fuel labeled E85 or
FlexFuel. Do not use gasoline with
ethanol levels greater than 15% by
volume.
Prohibited Fuels
Caution
Do not use fuels with any of the
following conditions; doing so may
damage the vehicle and void its
warranty:
.For vehicles that are not
FlexFuel, fuel labeled greater
than 15% ethanol by volume,
such as mid-level ethanol blends
(16–50% ethanol), E85,
or FlexFuel.
.Fuel with any amount of
methanol, methylal, ferrocene,
and aniline. These fuels can
corrode metal fuel system parts
or damage plastic and rubber
parts.
.Fuel containing metals such as
methylcyclopentadienyl
manganese tricarbonyl (MMT),
which can damage the emissions
control system and spark plugs.
.Fuel with a posted octane rating
of less than the recommended
fuel. Using this fuel will lower
(Continued)
Caution (Continued)
fuel economy and performance,
and may decrease the life of the
emissions catalyst.
Fuels in Foreign Countries
The U.S., Canada, and Mexico post
fuel octane ratings in anti-knock index
(AKI). For fuel not to use in a foreign
country, seeProhibited Fuels 0294.
Fuel Additives
TOP TIER Detergent Gasoline is highly
recommended for use with your
vehicle. If your country does not have
TOP TIER Detergent Gasoline, add
ACDelco Fuel System Treatment
Plus−Gasoline to the vehicle’s gasoline
fuel tank at every oil change or
15 000 km (9,000 mi), whichever
occurs first. TOP TIER Detergent
Gasoline and ACDelco Fuel System
Treatment Plus−Gasoline will help
keep your vehicle’s engine fuel deposit
free and performing optimally.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
298 DRIVING AND OPERATING
.Do not tow a trailer during the first
800 km (500 mi) of vehicle use to
prevent damage to the engine, axle,
or other parts.
.It is recommended to perform the
first oil change before heavy towing.
.During the first 800 km (500 mi) of
trailer towing, do not drive over
80 km/h (50 mph) and do not make
starts at full throttle.
.Vehicles can tow in D (Drive). If the
transmission downshifts too often, a
lower gear may be selected using
Manual Mode. SeeManual Mode
(Electronic Shifter) 0235 or
Manual Mode (Mechanical Shifter)
0 234.
If equipped, the following driver
assistance features should be turned
off when towing a trailer:
.Adaptive Cruise Control (ACC)
.Super Cruise Control
.Lane Keep Assist (LKA)
.Park Assist
.Automatic Parking Assist (APA)
.Reverse Automatic Braking (RAB) If equipped, the following driver
assistance features should be turned
to alert or off when towing a trailer:
.Automatic Emergency
Braking (AEB)
.Intelligent Brake Assist (IBA)
.Front Pedestrian Braking (FPB)
If equipped with Lane Change Alert
(LCA), the LCA detection zones that
extend back from the side of the
vehicle do not move further back
when a trailer is towed. Use caution
while changing lanes when towing a
trailer.
If equipped with Rear Cross Traffic
Alert (RCTA), use caution while
backing up when towing a trailer, as
the RCTA detection zones that extend
out from the back of the vehicle do
not move further back when a trailer
is towed.
{Warning
To prevent serious injury or death
from carbon monoxide (CO), when
towing a trailer:
.Do not drive with the liftgate,
trunk/hatch, or rear-most
window open.
.Fully open the air outlets on or
under the instrument panel.
.Adjust the climate control
system to a setting that brings in
only outside air. See “Climate
Control Systems” in the Index.
For more information about carbon
monoxide, see Engine Exhaust
0 226.
Towing a trailer requires experience.
The combination of the vehicle and
trailer is longer and not as responsive
as the vehicle itself. Get used to the
handling and braking of the
combination by driving on a level road
surface before driving on public roads.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
300 DRIVING AND OPERATING
When towing at higher altitudes,
engine coolant will boil at a lower
temperature than at lower altitudes.
If the engine is turned off immediately
after towing at high altitude on steep
uphill grades, the vehicle could show
signs similar to engine overheating. To
avoid this, let the engine run,
preferably on level ground, with the
transmission in P (Park) for a few
minutes before turning the engine off.
If the overheat warning comes on, see
Engine Overheating0322.
Parking on Hills
{Warning
To prevent serious injury or death,
always park your vehicle and trailer
on a level surface when possible.
When parking your vehicle and your
trailer on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn the
wheels into the curb if facing
downhill or into traffic if facing
uphill. 2. Have someone place chocks under
the trailer wheels.
3. When the wheel chocks are in place, gradually release the brake
pedal to allow the chocks to absorb
the load of the trailer.
4. Reapply the brake pedal. Then apply the parking brake and shift
into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
.Start the engine.
.Shift into a gear.
.Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance when Trailer
Towing
The vehicle needs service more often
when used to tow trailers. See
Maintenance Schedule 0380. It is
especially important to check the automatic transmission fluid, engine
oil, axle lubricant, belts, cooling
system, and brake system before and
during each trip.
Check periodically that all nuts and
bolts on the trailer hitch are tight.
Engine Cooling when Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See
Engine Overheating
0 322.
Trailer Towing (LSY 2.0L L4
Engine)
Caution
Towing a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To tow a trailer
correctly, follow the directions in
this section and see your dealer for
important information about
towing a trailer with the vehicle.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
304 VEHICLE CARE
Vehicle Care
General Information
General Information . . . . . . . . . . . . . 305
California Proposition65 Warning . . . . . . . . . . . . . . . . . . . . . 305
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . 306
Accessories and Modifications . . . . . . . . . . . . . . . . . . . 306
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . . . . . . 306
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . . . . . . 309
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . 312
Engine Oil Life System . . . . . . . . . . . 314
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315
Engine Air Filter Life System . . . . 315
Engine Air Cleaner/Filter . . . . . . . . . 316
Cooling System . . . . . . . . . . . . . . . . . . . 317
Engine Overheating . . . . . . . . . . . . . . 322
Washer Fluid . . . . . . . . . . . . . . . . . . . . . 323
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323 Brake Pad Life System (If
Equipped) . . . . . . . . . . . . . . . . . . . . . . . 324
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . 325
Battery - North America . . . . . . . . . 326
All-Wheel Drive . . . . . . . . . . . . . . . . . . 327
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . 327
Wiper Blade Replacement . . . . . . . 327
Windshield Replacement . . . . . . . . 328
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . 328
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . 329
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . 329
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . 330
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . . . . . 330
LED Lighting . . . . . . . . . . . . . . . . . . . . . 330
Front Turn Signal Lamps . . . . . . . . 330
Electrical System
Electrical System Overload . . . . . . 330
Fuses and Circuit Breakers . . . . . . 331
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332
Instrument Panel Fuse Block . . . . 334
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339
All-Season Tires . . . . . . . . . . . . . . . . . . 339
Winter Tires . . . . . . . . . . . . . . . . . . . . . . 340
Run-Flat Tires . . . . . . . . . . . . . . . . . . . . 340
Self-Sealing Tires . . . . . . . . . . . . . . . . . 341
Low-Profile Tires . . . . . . . . . . . . . . . . . 341
Summer Tires . . . . . . . . . . . . . . . . . . . . 341
Tire Sidewall Labeling . . . . . . . . . . . 342
Tire Designations . . . . . . . . . . . . . . . . . 343
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . . . . . 344
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 346
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . 347
Tire Pressure Monitor System . . . 348
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . . . . . . 349
Tire Inspection . . . . . . . . . . . . . . . . . . . 352
Tire Rotation . . . . . . . . . . . . . . . . . . . . . 352
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 353
Buying New Tires . . . . . . . . . . . . . . . . 354
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . . . . . 356
Uniform Tire Quality Grading . . . 356
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . . . . . . 357

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
310 VEHICLE CARE
1. Windshield Washer Fluid Reservoir.See Washer Fluid 0323.
2. Engine Coolant Surge Tank and Pressure Cap. See Cooling System
0 317.
3. Engine Air Cleaner/Filter 0316.
4. Engine Cooling Fan (Out of View). See Cooling System 0317.
5. Engine Oil Fill Cap. See Engine Oil
0 312.
6. Engine Oil Dipstick. See Engine Oil
0 312.
7. Remote Positive (+) Battery Terminal. See Jump Starting - North
America 0366.
8. Brake Fluid Reservoir. See Brake
Fluid 0325.
9. Remote Negative (-) Battery Terminal. See Jump Starting - North
America 0366.
10. Engine Compartment Fuse Block
0332.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
VEHICLE CARE 311
2.7L L4 Engine
1. Windshield Washer Fluid Reservoir. See Washer Fluid 0323.
2. Engine Coolant Surge Tank and Pressure Cap. See Cooling System
0 317.
3. Engine Air Cleaner/Filter 0316. 4. Engine Cooling Fan (Out of View).
See Cooling System 0317.
5. Engine Oil Fill Cap. See Engine Oil
0 312.
6. Cooling System Air Bleeder Cap. See Cooling System 0317. 7. Engine Oil Dipstick. See
Engine Oil
0 312.
8. Remote Positive (+) Battery Terminal. See Jump Starting - North
America 0366.