2021 CADILLAC CT4 fuel

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
VEHICLE CARE 349
soon as possible, and inflate them to
the proper pressure. Driving on a
significantly under-inflated tire causes
the tire to overheat and can lead to
tire failure. Under-inflation also
reduces fuel efficiency and tire tread
life, and may affect the vehicle's
handling and stopping ability.
Please note that the TPMS is not a
substitute for proper tire maintenance,
and it is the driver's responsibility to
maintain correct tire pressure, even if
under-inflation has not reached the
level to trigger illumination of the
TPMS low tire pressure telltale.
Your vehicle has also been equipped
with a TPMS malfunction indicator to
indicate when the system is not
operating properly. The TPMS
malfunction indicator is combined
with the low tire pressure telltale.
When the system detects a
malfunction, the telltale will flash for
approximately one minute and then
remain continuously illuminated. This
sequence will continue upon
subsequent vehicle start-ups as long
as the malfunction exists.When the malfunction indicator is
illuminated, the system may not be
able to detect or signal low tire
pressure as intended. TPMS
malfunctions may occur for a variety
of reasons, including the installation
of replacement or alternate tires or
wheels on the vehicle that prevent the
TPMS from functioning properly.
Always check the TPMS malfunction
telltale after replacing one or more
tires or wheels on your vehicle to
ensure that the replacement or
alternate tires and wheels allow the
TPMS to continue to function
properly.
See
Tire Pressure Monitor Operation
0 349.
See Radio Frequency Statement 0409.
Tire Pressure Monitor
Operation
This vehicle may have a Tire Pressure
Monitor System (TPMS). The TPMS is
designed to warn the driver when a
low tire pressure condition exists. TPMS sensors are mounted onto each
tire and wheel assembly, excluding the
spare tire and wheel assembly. The
TPMS sensors monitor the air
pressure in the tires and transmit the
tire pressure readings to a receiver
located in the vehicle.
When a low tire pressure condition is
detected, the TPMS illuminates the
low tire pressure warning light located
on the instrument cluster. If the
warning light comes on, stop as soon
as possible and inflate the tires to the
recommended pressure shown on the
Tire and Loading Information label.
See
Vehicle Load Limits 0214.
A message to check the pressure in a
specific tire displays in the Driver
Information Center (DIC). The low tire
pressure warning light and the DIC
warning message come on at each
ignition cycle until the tires are
inflated to the correct inflation

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
372 VEHICLE CARE
Carbon Fiber Care
Carbon fiber composite parts can be
washed and waxed like any other
parts. Use a clear or black pigmented
wax. SeeComposite Materials 0218.
Protecting Exterior Bright Metal
Moldings
Caution
Failure to clean and protect the
bright metal moldings can result in
a hazy white finish or pitting. This
damage would not be covered by
the vehicle warranty.
The bright metal moldings on the
vehicle are aluminum, chrome or
stainless steel. To prevent damage
always follow these cleaning
instructions:
.Be sure the molding is cool to the
touch before applying any cleaning
solution.
.Use only approved cleaning
solutions for aluminum, chrome or
stainless steel. Some cleaners are
highly acidic or contain alkaline
substances and can damage the
moldings.
.Always dilute a concentrated
cleaner according to the
manufacturer’s instructions.
.Do not use cleaners that are not
intended for automotive use.
.Use a nonabrasive wax on the
vehicle after washing to protect and
extend the molding finish.
Cleaning Exterior Lamps/Lenses,
Emblems, Decals, and Stripes
Use only lukewarm or cold water, a
soft cloth, and a car washing soap to
clean exterior lamps, lenses, emblems,
decals, and stripes. Follow instructions
under "Washing the Vehicle"
previously in this section.
Lamp covers are made of plastic, and
some have a UV protective coating. Do
not clean or wipe them when dry.
Do not use any of the following on
lamp covers:
.Abrasive or caustic agents.
.Washer fluids and other cleaning
agents in higher concentrations
than suggested by the manufacturer.
.Solvents, alcohols, fuels, or other
harsh cleaners.
.Ice scrapers or other hard items.
.Aftermarket appearance caps or
covers while the lamps are
illuminated, due to excessive heat
generated.
Caution
Failure to clean lamps properly can
cause damage to the lamp cover
that would not be covered by the
vehicle warranty.
Caution
Using wax on low gloss black finish
stripes can increase the gloss level
and create a non-uniform finish.
Clean low gloss stripes with soap
and water only.
Air Intakes
Clear debris from the air intakes,
between the hood and windshield,
when washing the vehicle.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
VEHICLE CARE 373
Shutter System
The vehicle may have a shutter
system designed to help improve fuel
economy. Keep the shutter system
clear of debris, snow and ice. If the
check engine light is activated, please
check to see if the shutter system is
clear of debris, snow or ice.
Windshield and Wiper Blades
Clean the outside of the windshield
with glass cleaner.
Clean rubber blades using a lint-free
cloth or paper towel soaked with
windshield washer fluid or a mild
detergent. Wash the windshield
thoroughly when cleaning the blades.Bugs, road grime, sap, and a buildup
of vehicle wash/wax treatments may
cause wiper streaking.
Replace the wiper blades if they are
worn or damaged. Damage can be
caused by extreme dusty conditions,
sand, salt, heat, sun, snow, and ice.
Weatherstrips
Apply weatherstrip lubricant on
weatherstrips to make them last
longer, seal better, and not stick or
squeak. Lubricate weatherstrips at
least once a year. Hot, dry climates
may require more frequent
application. Black marks from rubber
material on painted surfaces can be
removed by rubbing with a clean
cloth. See
Recommended Fluids and
Lubricants 0391.
Tires
Use a stiff brush with tire cleaner to
clean the tires.
Caution
Using petroleum-based tire dressing
products on the vehicle may
damage the paint finish and/or
tires. When applying a tire dressing,
always wipe off any overspray from
all painted surfaces on the vehicle.
Wheels and Wheel Trim
Use a soft, clean cloth with mild soap
and water to clean the wheels. After
rinsing thoroughly with clean water,
dry with a soft, clean towel. A wax
may then be applied.
Caution
Chrome wheels and chrome wheel
trim may be damaged if the vehicle
is not washed after driving on roads
that have been sprayed with
magnesium chloride or calcium
chloride. These are used on roads
for conditions such as dust and ice.
Always wash the chrome with soap
and water after exposure.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
374 VEHICLE CARE
Caution
To avoid surface damage on wheels
and wheel trim, do not use strong
soaps, chemicals, abrasive polishes,
cleaners, or brushes. Use only GM
approved cleaners. Do not drive the
vehicle through an automatic car
wash that uses silicon carbide tire/
wheel cleaning brushes. Damage
could occur and the repairs would
not be covered by the vehicle
warranty.
Brake System
Visually inspect brake lines and hoses
for proper hook-up, binding, leaks,
cracks, chafing, etc. Inspect disc brake
pads for wear and rotors for surface
condition. Inspect drum brake linings/
shoes for wear or cracks. Inspect all
other brake parts.
Steering, Suspension, and
Chassis Components
Visually inspect steering, suspension,
and chassis components for damaged,
loose, or missing parts or signs of
wear at least once a year.Inspect power steering for proper
attachment, connections, binding,
leaks, cracks, chafing, etc.
Visually check constant velocity joint
boots and axle seals for leaks.
Body Component Lubrication
Lubricate all key lock cylinders, hood
hinges, liftgate hinges, and the steel
fuel door hinge, unless the
components are plastic. Applying
silicone grease on weatherstrips with a
clean cloth will make them last
longer, seal better, and not stick or
squeak.
Underbody Maintenance
At least twice a year, spring and fall,
use plain water to flush any corrosive
materials from the underbody. Take
care to thoroughly clean any areas
where mud and other debris can
collect.
Do not directly power wash the
transfer case and/or front/rear axle
output seals. High pressure water can
overcome the seals and contaminate
the fluid. Contaminated fluid will
decrease the life of the transfer case
and/or axles and should be replaced
Sheet Metal Damage
If the vehicle is damaged and requires
sheet metal repair or replacement,
make sure the body repair shop
applies anti-corrosion material to
parts repaired or replaced to restore
corrosion protection.
Original manufacturer replacement
parts will provide the corrosion
protection while maintaining the
vehicle warranty.
Finish Damage
Quickly repair minor chips and
scratches with touch-up materials
available from your dealer to avoid
corrosion. Larger areas of finish
damage can be corrected in your
dealer's body and paint shop.
Chemical Paint Spotting
Airborne pollutants can fall upon and
attack painted vehicle surfaces
causing blotchy, ring-shaped
discolorations, and small, irregular

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
380 SERVICE AND MAINTENANCE
keep the vehicle in good working
condition, improves fuel economy, and
reduces vehicle emissions.
Because of the way people use
vehicles, maintenance needs vary.
There may need to be more frequent
checks and services. The Additional
Required Services - Normal are for
vehicles that:
.Carry passengers and cargo within
recommended limits on the Tire
and Loading Information label. See
Vehicle Load Limits0214.
.Are driven on reasonable road
surfaces within legal driving limits.
.Use the recommended fuel. See
Recommended Fuel (LSY 2.0L L4
Turbo Engine) 0293 or
Recommended Fuel (L3B 2.7L L4
Turbo Engine) 0294.
Refer to the information in the
Maintenance Schedule Additional
Required Services - Normal chart. The Additional Required Services -
Severe are for vehicles that are:
.Mainly driven in heavy city traffic
in hot weather.
.Mainly driven in hilly or
mountainous terrain.
.Used for high speed or competitive
driving.
.Used for taxi, police, or delivery
service.
Refer to the information in the
Maintenance Schedule Additional
Required Services - Severe chart.
{Warning
Performing maintenance work can
be dangerous and can cause serious
injury. Perform maintenance work
only if the required information,
proper tools, and equipment are
available. If they are not, see your
dealer to have a trained technician
do the work. See Doing Your Own
Service Work 0306.
Maintenance Schedule
Owner Checks and Services
Check the engine oil level. See Engine
Oil 0312.
Once a Month
.Check the tire inflation pressures.
See Tire Pressure 0346.
.Inspect the tires for wear. See Tire
Inspection 0352.
.Check the windshield washer fluid
level. See Washer Fluid 0323.
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

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
382 SERVICE AND MAINTENANCE
.Visually inspect halfshafts and drive
shafts for excessive wear, lubricant
leaks, and/or damage including:
tube dents or cracks, constant
velocity joint or universal joint
looseness, cracked or missing boots,
loose or missing boot clamps, center
bearing excessive looseness, loose or
missing fasteners, and axle seal
leaks.
.Check restraint system components.
SeeSafety System Check 047.
.Visually inspect fuel system for
damage or leaks.
.Visually inspect exhaust system and
nearby heat shields for loose or
damaged parts.
.Lubricate body components. See
Exterior Care 0370.
.Check parking brake and automatic
transmission park mechanism. See
Park Brake and P (Park) Mechanism
Check 0327.
.Check accelerator pedal for damage,
high effort, or binding. Replace if
needed.
.Visually inspect gas strut for signs
of wear, cracks, or other damage.
Check the hold open ability of the
strut. If the hold open is low,
service the gas strut. See Gas
Strut(s) 0328.
.Inspect sunroof track and seal,
if equipped. See Sunroof028.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
SERVICE AND MAINTENANCE 385
Footnotes—Maintenance Schedule
Additional Required Services -
Normal
(1) Vehicles with different size front
and rear tires do not have tire
rotation. See Tire Rotation0352.
(2) Or every two years, whichever
comes first. More frequent passenger
compartment air filter replacement
may be needed if driving in areas with
heavy traffic, poor air quality, high
dust levels, or environmental
allergens. Passenger compartment air
filter replacement may also be needed
if there is reduced airf low, window
fogging, or odors. Your GM dealer can
help determine when to replace the
filter.
(3) Or every four years, whichever
comes first. If driving in dusty
conditions, inspect the filter at each
oil change or more often as needed.
See Engine Air Cleaner/Filter 0316.
(4) Visually check all fuel and vapor
lines and hoses for proper attachment,
connection, routing, and condition. (5)
Do not directly power wash the
transfer case and/or front/rear axle
output seals. High pressure water can
overcome the seals and contaminate
the transfer case fluid. Contaminated
fluid will decrease the life of the
transfer case and/or axles and should
be replaced.
(6) Or every five years, whichever
comes first. See Cooling System0317.
(7) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage; replace,
if needed.
(8) Replace brake fluid every five
years. See Brake Fluid 0325.
(9) Or every 12 months, whichever
comes first. See Wiper Blade
Replacement 0327.
(10) Or every 10 years, whichever
comes first. See Gas Strut(s)0328.
(11) Replace air conditioning
desiccant every seven years.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
388 SERVICE AND MAINTENANCE
Footnotes—Maintenance Schedule
Additional Required Services -
Severe
(1) Vehicles with different size front
and rear tires do not have tire
rotation. See Tire Rotation0352.
(2) Or every two years, whichever
comes first. More frequent passenger
compartment air filter replacement
may be needed if driving in areas with
heavy traffic, poor air quality, high
dust levels, or environmental
allergens. Passenger compartment air
filter replacement may also be needed
if there is reduced airf low, window
fogging, or odors. Your GM dealer can
help determine when to replace the
filter.
(3) Or every four years, whichever
comes first. If driving in dusty
conditions, inspect the filter at each
oil change or more often as needed.
See Engine Air Cleaner/Filter 0316.
(4) Visually check all fuel and vapor
lines and hoses for proper attachment,
connection, routing, and condition. (5)
Do not directly power wash the
transfer case and/or front/rear axle
output seals. High pressure water can
overcome the seals and contaminate
the transfer case fluid. Contaminated
fluid will decrease the life of the
transfer case and/or axles and should
be replaced.
(6) Or every five years, whichever
comes first. See Cooling System0317.
(7) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage; replace,
if needed.
(8) Replace brake fluid every five
years. See Brake Fluid 0325.
(9) Or every 10 years, whichever
comes first. See Gas Strut(s)0328.
(10) Replace air conditioning
desiccant every seven years.Special Application
Services
.Severe Commercial Use Vehicles
Only: Lubricate chassis components
every oil change.
.Have underbody flushing service
performed. See "Underbody
Maintenance" in Exterior Care0370.
Additional Maintenance
and Care
Your vehicle is an important
investment and caring for it properly
may help to avoid future costly
repairs. To maintain vehicle
performance, additional maintenance
services may be required.
It is recommended that your dealer
perform these services —their trained
dealer technicians know your vehicle
best. Your dealer can also perform a
thorough assessment with a
multi-point inspection to recommend
when your vehicle may need
attention.