2021 CADILLAC CT4 brake fluid

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
248 DRIVING AND OPERATING
Automatic Transmissions
.The brake pedal is firmly pressed to
the floor, equivalent to a panic
brake event.
.The accelerator pedal is rapidly
applied to wide open throttle. If the
vehicle rolls due to wide open
throttle, release the throttle, press
the brake pedal more firmly, and
re-apply the accelerator to wide
open throttle.
Launch Control will initially limit
engine speed as you rapidly apply the
accelerator pedal to wide open
throttle. Allow the engine rpm to
stabilize. A smooth, quick release of
the brake pedal, while maintaining the
fully pressed accelerator pedal, will
manage wheel slip.
After the vehicle is launched, the
system continues in Competitive
Driving Mode or PTM.
Competitive Driving Mode, PTM, and
Launch Control are systems designed
for a closed course race track and not
intended for public roads. The systems are not intended to compensate for
lack of driver experience or familiarity
with the race track.Limited-Slip Differential
If equipped, the Electronic
Limited-Slip Differential (eLSD) is
automatically activated. eLSD actively
monitors vehicle sensors and driver
inputs to determine the amount of
change for the conditions. With eLSD,
the vehicle has:
.Enhanced high-speed control.
.Improved traction through corners,
allowing more acceleration.
.More precise steering.
.Increased vehicle agility.
.Integration with StabiliTrak/
Electronic Stability Control (ESC).
For vehicles with eLSD, driven under
severe conditions, the rear axle fluid
should be changed. See Competitive
Driving Mode 0246 and
Maintenance Schedule 0380.
Cruise Control
{
Warning
Cruise control can be dangerous
where you cannot drive safely at a
steady speed. Do not use cruise
control on winding roads or in
heavy traffic.
Cruise control can be dangerous on
slippery roads. On such roads, fast
changes in tire traction can cause
excessive wheel slip, and you could
lose control. Do not use cruise
control on slippery roads.
With cruise control, a speed of about
40 km/h (25 mph) or more can be
maintained without keeping your foot
on the accelerator. Cruise control does
not work at speeds below about
40 km/h (25 mph).
If the Traction Control/StabiliTrak/
Electronic Stability Control (ESC)
system begins to limit wheel spin
while using cruise control, the cruise
control automatically disengages. See
Traction Control/Electronic Stability
Control 0239. If a collision alert

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
312 VEHICLE CARE
9. Brake Fluid Reservoir. SeeBrake
Fluid 0325.
10. Remote Negative (-) Battery Terminal. See Jump Starting - North
America 0366.
11. Engine Compartment Fuse Block. See Engine Compartment Fuse Block
0 332.
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” in this
section.
.Change the engine oil at the
appropriate time. See Engine Oil Life
System 0314.
.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 0309 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
improves when checking a cold
engine prior to starting. Remove the
dipstick and check the level.
.If unable to wait two hours, the
engine must be off for at least
15 minutes if the engine is warm,
or at least 30 minutes if the engine
is not warm. Pull out the dipstick,
wipe it with a clean paper towel or
cloth, then push it back in all the
way. Remove it again, keeping the
tip down, and check the level.
When to Add Engine Oil
If the oil is below the cross-hatched
area at the tip of the dipstick and the
engine has been off for at least
15 minutes, add 1 L (1 qt) of the
recommended oil and then recheck
the level. See
“Selecting the Right
Engine Oil” later in this section for an

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
VEHICLE CARE 323
back on, continue to drive normally
and have the cooling system checked
for proper fill and function.
If the warning continues, pull over,
stop, and park the vehicle right away.
If there is no sign of steam, idle the
engine for three minutes while parked.
If the warning is still displayed, turn
off the engine until it cools down.
Washer Fluid
What to Use
When windshield washer fluid is
needed, be sure to read the
manufacturer's instructions before
use. If operating the vehicle in an area
where the temperature may fall below
freezing, use a fluid that has sufficient
protection against freezing.
Adding Washer Fluid
Open the cap with the washer symbol
on it. Add washer fluid until the tank
is full. SeeEngine Compartment
Overview 0309 for reservoir location.
Caution
.Do not use washer fluid that
contains any type of water
repellent coating. This can cause
the wiper blades to chatter
or skip.
.Do not use engine coolant
(antifreeze) in the windshield
washer. It can damage the
windshield washer system and
paint.
.Do not mix water with
ready-to-use washer fluid. Water
can cause the solution to freeze
and damage the washer fluid
tank and other parts of the
washer system.
.When using concentrated washer
fluid, follow the manufacturer
instructions for adding water.
(Continued)
Caution (Continued)
.Fill the washer fluid tank only
three-quarters full when it is very
cold. This allows for fluid
expansion if freezing occurs,
which could damage the tank if
it is completely full.
Brakes
Disc brake linings have built-in wear
indicators that make a high-pitched
warning sound when the brake linings
are worn and new linings are needed.
The sound can come and go or can be
heard all the time when the vehicle is
moving, except when applying the
brake pedal firmly.
{Warning
The brake wear warning sound
means that soon the brakes will not
work well. That could lead to a
crash. When the brake wear
warning sound is heard, have the
vehicle serviced.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
VEHICLE CARE 325
How to Disable the Brake Pad
Life System
The brake pad life system can be
turned off. This may be necessary if
aftermarket brake pads without wear
sensors are installed. When the
system is turned off, the front and
rear brake pad life percentages will
not display. However, the built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn can still determine when the
pads should be replaced. SeeBrakes
0 323.
To turn off the brake pad life system: 1. Display Brake Pad Life on the DIC. See Driver Information Center (DIC)
(Base Level) 0107 or
Driver Information Center (DIC)
(Uplevel) 0110.
2. Select DISABLE.
To turn the brake pad life system back
on, follow the above steps but select
ENABLE in Step 2.
Brake Fluid
The brake master cylinder reservoir is
filled with GM approved DOT 4 brake
fluid as indicated on the reservoir cap.
See Engine Compartment Overview
0 309 for the location of the reservoir.
Checking Brake Fluid
With the vehicle in P (Park) on a level
surface, the brake fluid level should be
between the minimum and maximum
marks on the brake fluid reservoir.
There are only two reasons why the
brake fluid level in the reservoir may
go down:
.Normal brake lining wear. When
new linings are installed, the fluid
level goes back up.
.A fluid leak in the brake hydraulic
system. Have the brake hydraulic
system fixed. With a leak, the
brakes will not work well. Always clean the brake fluid reservoir
cap and the area around the cap
before removing it.
Do not top off the brake fluid. Adding
fluid does not correct a leak. If fluid is
added when the linings are worn,
there will be too much fluid when
new brake linings are installed. Add or
remove fluid, as necessary, only when
work is done on the brake hydraulic
system.
{Warning
If too much brake fluid is added, it
can spill on the engine and burn,
if the engine is hot enough. You or
others could be burned, and the
vehicle could be damaged. Add
brake fluid only when work is done
on the brake hydraulic system.
When the brake fluid falls to a low
level, the brake warning light comes
on. See Brake System Warning Light
0 99.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
326 VEHICLE CARE
Brake fluid absorbs water over time
which degrades the effectiveness of
the brake fluid. Replace brake fluid at
the specified intervals to prevent
increased stopping distance. See
Maintenance Schedule0380.
What to Add
Use only GM approved DOT 4 brake
fluid from a clean, sealed container.
See Recommended Fluids and
Lubricants 0391.
{Warning
The wrong or contaminated brake
fluid could result in damage to the
brake system. This could result in
the loss of braking leading to a
possible injury. Always use the
proper GM approved brake fluid.
Caution
If brake fluid is spilled on the
vehicle's painted surfaces, the paint
finish can be damaged. Immediately
wash off any painted surface.
Battery - North America
The original equipment battery is
maintenance free. Do not remove the
cap and do not add fluid.
Refer to the replacement number
shown on the original battery label
when a new battery is needed.
The vehicle has an Absorbed Glass
Mat (AGM) 12-volt battery.
Installation of a standard 12-volt
battery will result in reduced 12-volt
battery life.
When using a 12-volt battery charger
on the 12-volt AGM battery, some
chargers have an AGM battery setting
on the charger. If available, use the
AGM setting on the charger, to limit
charge voltage to 14.8 volts. Follow
the charger manufacturer's
instructions.
Stop/Start System
This vehicle has a Stop/Start system
to shut off the engine to help
conserve fuel. See Stop/Start System
0 221.{Warning
WARNING: Battery posts,
terminals, and related accessories
contain lead and lead compounds,
chemicals known to the State of
California to cause cancer and birth
defects or other reproductive harm.
Batteries also contain other
chemicals known to the State of
California to cause cancer. WASH
HANDS AFTER HANDLING. For
more information go to
www.P65Warnings.ca.gov/
passenger-vehicle.
See California Proposition 65 Warning
0 305 and the back cover.
Vehicle Storage
{Warning
Batteries have acid that can burn
you and gas that can explode. You
can be badly hurt if you are not
(Continued)