engine CADILLAC CT4 2020 Service Manual

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
DRIVING AND OPERATING 147
{Warning
Prior to each track event and again
before returning to public roads,
tighten the wheel nuts with a
torque wrench to the proper torque
specification. Wheel nuts that are
improperly or incorrectly tightened
can cause the wheels to become
loose or come off, resulting in a
crash. SeeCapacities and
Specifications 0318 for wheel nut
torque specifications.
Caution
Low oil levels can damage the
engine. If using the vehicle for
competitive driving, the engine may
use more oil than it would with
normal use. Check the oil level
often during competitive driving.
Competitive Driving Mode can be
selected. See Driver Mode Control
0 184.
Axle Fluid
Axles must have 805 km (500 mi)
before being used in track driving.
The rear axle fluid temperatures may
be higher than when driving in severe
conditions. Drain and refill with new
fluid after the first racing or
competitive driving event, and then
after every 24 hours of racing or
competitive driving. See Recommended
Fluids and Lubricants 0313.
Caution
During a first time track or racing
event, high axle temperatures can
occur. Damage could be caused to
the axle and would not be covered
by the vehicle warranty. Do not
drive as long or as fast the first
time the vehicle is driven on the
track or raced.
. The axle lubricant should be
replaced with new lubricant.
. Additional cooling capacity is also
required for continuous
competitive driving.
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 wheel

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
148 DRIVING AND OPERATING
speed 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 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 0313.
. 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
performance or race track driving.
See
Recommended Fluids and
Lubricants 0313.
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
0157.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
152 DRIVING AND OPERATING
{Warning
Using the brakes to slow the vehicle
on a long downhill slope can cause
brake overheating, can reduce brake
performance, and could result in a
loss of braking. Shift the
transmission to a lower gear to let
the engine assist the brakes on a
steep downhill slope.
{Warning
Coasting downhill in N (Neutral) or
with the ignition off is dangerous.
This can cause overheating of the
brakes and loss of steering assist.
Always have the engine running
and the vehicle in gear.
. Drive at speeds that keep the
vehicle in its own lane. Do not
swing wide or cross the
center line. .
Be alert on top of hills; something
could be in your lane (e.g., stalled
car, crash).
. Pay attention to special road signs
(e.g., falling rocks area, winding
roads, long grades, passing or
no-passing zones) and take
appropriate action.
Winter Driving
Driving on Snow or Ice
Snow or ice between the tires and the
road creates less traction or grip, so
drive carefully. Wet ice can occur at
about 0 °C (32 °F) when freezing rain
begins to fall. Avoid driving on wet ice
or in freezing rain until roads can be
treated.
For Slippery Road Driving:
.Accelerate gently. Accelerating too
quickly causes the wheels to spin
and makes the surface under the
tires slick.
. Turn on Traction Control. See
Traction Control/Electronic Stability
Control 0182. .
Antilock Brake System (ABS)
improves vehicle stability during
hard stops, but the brakes should
be applied sooner than when on
dry pavement. See Antilock Brake
System (ABS) 0179.
. Allow greater following distance
and watch for slippery spots. Icy
patches can occur on otherwise
clear roads in shaded areas. The
surface of a curve or an overpass
can remain icy when the
surrounding roads are clear. Avoid
sudden steering maneuvers and
braking while on ice.
. Turn off cruise control.
Blizzard Conditions
Stay with the vehicle unless there is
help nearby. If possible, use Roadside
Assistance. See Roadside Service 0325.
To get help and keep everyone in the
vehicle safe:
. Turn on the hazard warning
flashers.
. Tie a red cloth to an outside
mirror.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
DRIVING AND OPERATING 153
{Warning
Snow can trap engine exhaust
under the vehicle. This may cause
exhaust gases to get inside. Engine
exhaust contains carbon monoxide
(CO), which cannot be seen or
smelled. It can cause
unconsciousness and even death.
If the vehicle is stuck in snow:. Clear snow from the base of
the vehicle, especially any
blocking the exhaust pipe.
. Open a window about 5 cm
(2 in) on the vehicle side that
is away from the wind, to
bring in fresh air.
. Fully open the air outlets on
or under the instrument
panel.
. Adjust the climate control
system to circulate the air
inside the vehicle and set the
(Continued)
Warning (Continued)
fan speed to the highest
setting. See“Climate Control
Systems.”
For more information about CO, see
Engine Exhaust 0168.
To save fuel, run the engine for short
periods to warm the vehicle and then
shut the engine off and partially close
the window. Moving about to keep
warm also helps.
If it takes time for help to arrive,
when running the engine, push the
accelerator pedal slightly so the
engine runs faster than the idle speed.
This keeps the battery charged to
restart the vehicle and to signal for
help with the headlamps. Do this as
little as possible, to save fuel.
If the Vehicle Is Stuck
Slowly and cautiously spin the wheels
to free the vehicle when stuck in sand,
mud, ice, or snow. If stuck too severely for the traction
system to free the vehicle, turn the
traction system off and use the
rocking method. See
Traction Control/
Electronic Stability Control 0182.
{Warning
If the vehicle's tires spin at high
speed, they can explode, and you or
others could be injured. The vehicle
can overheat, causing an engine
compartment fire or other damage.
Spin the wheels as little as possible
and avoid going above 56 km/h
(35 mph).
Rocking the Vehicle to Get it Out
Turn the steering wheel left and right
to clear the area around the front
wheels. Turn off any traction system.
Shift back and forth between
R (Reverse) and a low forward gear,
spinning the wheels as little as
possible. To prevent transmission
wear, wait until the wheels stop
spinning before shifting gears. Release
the accelerator pedal while shifting,
and press lightly on the accelerator

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
DRIVING AND OPERATING 157
{Warning
Things inside the vehicle can
strike and injure people in a
sudden stop or turn, or in a
crash.
.Put things in the cargo
area of the vehicle. In the
cargo area, put them as far
forward as possible. Try to
spread the weight evenly.
.Never stack heavier things,
like suitcases, inside the
vehicle so that some of
them are above the tops of
the seats.
.Do not leave an unsecured
child restraint in the
vehicle.
.Secure loose items in the
vehicle.
.Do not leave a seat folded
down unless needed.
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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
158 DRIVING AND OPERATING
{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.
Ignition Positions
The vehicle has an electronic keyless
ignition with pushbutton start.
The remote key must be in the vehicle
for the system to operate. If the
pushbutton start is not working, thevehicle may be near a strong radio
antenna signal causing interference to
the Keyless Access system. See
Remote
Keyless Entry (RKE) System Operation
0 8.
To shift out of P (Park), the vehicle
must be on, and the brake pedal must
be applied.
Stopping the Engine/OFF (No
Indicator Lights) : When the vehicle
is stopped, press ENGINE START/
STOP once to turn the engine off.
If the vehicle is in P (Park), the
ignition will turn off, and Retained
Accessory Power (RAP) will remain
active. See Retained Accessory Power
(RAP) 0163.
If the vehicle is not in P (Park), the
ignition will return to ACC/
ACCESSORY and display a message in
the Driver Information Center (DIC).
When the vehicle is shifted into
P (Park), the ignition system will
switch to OFF.
The vehicle may have an electric
steering column lock. The lock is
activated when the vehicle is switched
to OFF and the driver door is opened.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
DRIVING AND OPERATING 159
A sound may be heard as the lock
actuates or releases. The steering
column lock may not release with the
wheels turned off center. If this
happens, the vehicle may not start.
Move the steering wheel from left to
right while attempting to start the
vehicle. If this does not work, the
vehicle needs service.
Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake and
steering systems and disable the
airbags.
If the vehicle must be shut off in an
emergency:1. Brake using a firm and steady pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.
2. Shift the vehicle to N (Neutral). This can be done while the
vehicle is moving. After shifting
to N (Neutral), firmly apply the
brakes and steer the vehicle to a
safe location. 3. Come to a complete stop, shift to
P (Park), and turn the ignition to
OFF. On vehicles with an
automatic transmission, the shift
lever must be in P (Park) to turn
the ignition switch to the OFF
position.
4. Set the parking brake. See Electric Parking Brake 0179.
{Warning
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, only shut the vehicle
off in an emergency.
If the vehicle cannot be pulled over,
and must be shut off while driving,
press and hold the ENGINE START/
STOP button for longer than
two seconds, or press twice in
five seconds. ACC/ACCESSORY (Amber Indicator
Light) :
This mode allows you to use
some electrical accessories when the
engine is off.
With the ignition off, pressing the
button one time without the brake
pedal applied will place the ignition
system in ACC/ACCESSORY.
The ignition will switch from ACC/
ACCESSORY to OFF after five minutes
to prevent battery rundown.
ON/RUN/START (Green Indicator
Light) : This mode is for driving and
starting. With the ignition off, and the
brake pedal applied, pressing the
button once will place the ignition
system in ON/RUN/START. Once
engine cranking begins, release the
button. Engine cranking will continue
until the engine starts. See Starting the
Engine 0160. The vehicle will then
remain on.
Service Mode
This power mode is available for
service and diagnostics, and to verify
the proper operation of the
malfunction indicator lamp as may be
required for emission inspection

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
160 DRIVING AND OPERATING
purposes. With the vehicle off, and the
brake pedal not applied, pressing and
holding the button for more than
five seconds will place the vehicle in
Service Mode. The instruments and
audio systems will operate as they do
in ON/RUN, but the vehicle will not be
able to be driven. The engine will not
start in Service Mode. Press the
button again to turn the vehicle off.
Starting the Engine
Shift to P (Park) or N (Neutral). To
restart the engine when the vehicle is
already moving, use N (Neutral) only.
Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you
could damage the transmission.
Shift to P (Park) only when the
vehicle is stopped.
Caution
If you add electrical parts or
accessories, you could change the
way the engine operates. Any
resulting damage would not be
covered by the vehicle warranty. See
Add-On Electrical Equipment0231.
Starting Procedure 1. With the Keyless Access system, the remote key must be in the
vehicle. Press ENGINE START/
STOP with the brake pedal
applied. When the engine begins
cranking, let go of the button.
The idle speed will go down as
the engine gets warm. Do not
race the engine immediately
after starting it.
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) will display a
message. See Remote Keyless
Entry (RKE) System Operation 08.
Caution
Cranking the engine for long
periods of time, by trying to start
the engine 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 holding it there
as you press ENGINE START/
STOP. Wait at least 15 seconds
between each try, to allow the
cranking motor to cool down.
When the engine starts, release
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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
DRIVING AND OPERATING 161
Operate the engine and
transmission gently until the oil
warms up and lubricates all
moving parts.
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 096. When the brake
pedal is released or the accelerator
pedal is pressed, the engine will
restart.
To maintain vehicle performance,
other conditions may cause the engine
to automatically restart before the
brake pedal is released.
Auto Stops may not occur and/or Auto
Starts may occur because:
. The climate control settings
require the engine to be running
to cool or heat the vehicle interior.
. The vehicle battery charge is low.
. The vehicle battery has recently
been disconnected.
. Minimum vehicle speed has not
been reached since the last
Auto Stop.
. The accelerator pedal is pressed.
. The engine or transmission is not
at the required operating
temperature.
. The outside temperature is not in
the required operating range. .
The vehicle transmission is shifted
out of D (Drive) to any gear other
than P (Park).
. Tow/Haul Mode or other driver
modes have been selected.
. The vehicle is on a steep hill or
grade.
. The driver door has been opened
or the driver seat belt has been
unbuckled.
. The hood has been opened.
. The Auto Stop has reached the
maximum allowed time.
Auto Stop Disable Switch

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
162 DRIVING AND OPERATING
The automatic engine Stop/Start
feature can be disabled and enabled
by pressing the switch with the
h
symbol. Auto Stop is enabled each
time you start the vehicle.
When
his illuminated, the system is
enabled.
Engine Heater
Vehicles with the engine heater can
use this option in cold weather
conditions at or below −18 °C (0 °F) for
easier starting and better fuel
economy during engine warm-up. Plug
in the engine heater at least four
hours before starting your vehicle. An
internal thermostat in the plug-end of
the cord may exist which will prevent
engine heater operation at
temperatures above −18 °C (0 °F).
The engine heater cord requires the
front license plate mounting bracket
to be installed. See your dealer for
more information.
To Use the Engine Heater
1. Turn off the engine. 2. Open the hood and unwrap the
electrical cord. The cord is
clipped to the diagonal brace on
the passenger side of the engine
compartment.
Check the heater cord for
damage. If it is damaged, do not
use it. See your dealer for a
replacement. Inspect the cord for
damage yearly.
3. Plug it into a normal, grounded 110-volt AC outlet.
{Warning
Improper use of the heater cord or
an extension cord can damage the
cord and may result in overheating
and fire.
. Plug the cord into a
three-prong electrical utility
receptacle that is protected by
a ground fault detection
(Continued)
Warning (Continued)
function. An ungrounded
outlet could cause an electric
shock.
. Use a weatherproof,
heavy-duty, 15 amp-rated
extension cord if needed.
Failure to use the
recommended extension cord
in good operating condition,
or using a damaged heater or
extension cord, could make it
overheat and cause a fire,
property damage, electric
shock, and injury.
. Do not operate the vehicle
with the heater cord
permanently attached to the
(Continued)