2021 CADILLAC CT4 tire replacement

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
VEHICLE CARE 341
When driving on a deflated run-flat
tire, avoid potholes and other road
hazards that could damage the tire
and/or wheel beyond repair. When a
tire has been damaged, or if driven
any distance while deflated, check
with an authorized run-flat tire
service center to determine whether
the tire can be repaired or should be
replaced. To maintain the run-flat
feature, all replacement tires must be
run-flat tires.
To locate the nearest GM or run-flat
servicing facility, call Customer
Assistance.
Self-Sealing Tires
This vehicle may have self-sealing
tires. These tires have a material
inside that can seal punctures from
common road hazards, such as nails
and screws, in the tread area. The tire
may lose air pressure if the sidewall is
damaged or the tread puncture is too
large. If the Tire Pressure Monitor
System indicates the tire pressure is
low, inspect the tire for damage and
inflate it to the recommended
pressure. If the tire is unable to
maintain the recommended pressure,contact the nearest authorized GM
servicing facility immediately for
inspection and repair or replacement.
To locate the nearest GM servicing
facility, call GM Customer Assistance.
Caution
Do not drive on a deflated
self-sealing tire as this could
damage the tire. Make sure the tire
is inflated to the recommended
pressure or have it immediately
repaired or replaced.
When tire replacement is needed
replace with a self-sealing tire,
because the vehicle does not come
with a spare tire or tire changing
equipment.
Low-Profile Tires
If the vehicle has 225/45R17 91V,
235/40R18 91V, 235/40R18 XL
95Y, or 235/35R19 XL 91V size
tires, they are classified as
low-profile tires. Caution
Low-profile tires are more
susceptible to damage from road
hazards or curb impact than
standard profile tires. Tire and/or
wheel assembly damage can occur
when coming into contact with
road hazards like potholes, or sharp
edged objects, or when sliding into
a curb. The warranty does not cover
this type of damage. Keep tires set
to the correct inflation pressure and
when possible, avoid contact with
curbs, potholes, and other road
hazards.
Summer Tires
High Performance Summer Tires
This vehicle may come with
235/40R18 XL 95Y high performance
summer tires. These tires have a
special tread and compound that are
optimized for maximum dry and wet
road performance. This special tread
and compound will have decreased
performance in cold climates, and on
ice and snow. It is recommended that
winter tires be installed on the vehicle

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
VEHICLE CARE 351
message should go off after
successfully completing the sensor
matching process. See "TPMS
Sensor Matching Process" later in
this section.
.One or more TPMS sensors are
missing or damaged. The
malfunction light and the DIC
message should go off when the
TPMS sensors are installed and the
sensor matching process is
performed successfully. See your
dealer for service.
.Replacement tires or wheels do not
match the original equipment tires
or wheels. Tires and wheels other
than those recommended could
prevent the TPMS from functioning
properly. SeeBuying New Tires
0 354.
.Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning
properly it cannot detect or signal a
low tire pressure condition. See your dealer for service if the TPMS
malfunction light and DIC message
come on and stay on.
Tire Fill Alert (If Equipped)
This feature provides visual and
audible alerts outside the vehicle to
help when inflating an underinflated
tire to the recommended cold tire
pressure.
When the low tire pressure warning
light comes on:
1. Park the vehicle in a safe, level place.
2. Set the parking brake firmly.
3. Place the vehicle in P (Park).
4. Add air to the tire that is underinflated. The turn signal lamp
will flash.
When the recommended pressure
is reached, the horn sounds once
and the turn signal lamp will stop
flashing and briefly turn solid.
Repeat these steps for all
underinflated tires that have
illuminated the low tire pressure
warning light.
{Warning
Overinflating a tire could cause the
tire to rupture and you or others
could be injured. Do not exceed the
maximum pressure listed on the
tire sidewall. See Tire Sidewall
Labeling 0342 and
Vehicle Load Limits 0214.
If the tire is overinflated by more than
35 kPa (5 psi), the horn will sound
multiple times and the turn signal
lamp will continue to flash for several
seconds after filling stops. To release
and correct the pressure, while the
turn signal lamp is still flashing,
briefly press the center of the valve
stem. When the recommended
pressure is reached, the horn
sounds once.
If the turn signal lamp does not flash
within 15 seconds after starting to
inflate the tire, the tire fill alert has
not been activated or is not working.
If the hazard warning flashers are on,
the tire fill alert visual feedback will
not work properly.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
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VEHICLE CARE 353
rotation, check the wheel
alignment. SeeWhen It Is Time for
New Tires 0353 and
Wheel Replacement 0357.
Use this rotation pattern when
rotating the tires.
Adjust the front and rear tires to
the recommended inflation
pressure on the Tire and Loading
Information label after the tires
have been rotated. See Tire
Pressure 0346 and
Vehicle Load Limits 0214. Reset the Tire Pressure Monitor
System. See
Tire Pressure Monitor
Operation 0349.
Check that all wheel nuts are
properly tightened. See “Wheel
Nut Torque ”under Capacities and
Specifications 0396.
{Warning
Rust or dirt on a wheel, or on
the parts to which it is fastened,
can cause wheel nuts to become
loose over time. The wheel
could come off and cause a
crash. When changing a wheel,
remove any rust or dirt from
places where the wheel attaches
to the vehicle. In an emergency,
a cloth or paper towel can be
used; however, use a scraper or
wire brush later to remove all
rust or dirt. Lightly coat the inner diameter of
the wheel hub opening with wheel
bearing grease after a wheel
change or tire rotation to prevent
corrosion or rust build-up.
{Warning
Do not apply grease to the
wheel mounting surface, wheel
conical seats, or the wheel nuts
or bolts. Grease applied to these
areas could cause a wheel to
become loose or come off,
resulting in a crash.
When It Is Time for New
Tires
Factors, such as maintenance,
temperatures, driving speeds, vehicle
loading, and road conditions affect the
wear rate of the tires.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
354 VEHICLE CARE
Treadwear indicators are one way to
tell when it is time for new tires.
Treadwear indicators appear when the
tires have only 1.6 mm (1/16 in) or
less of tread remaining. SeeTire
Inspection 0352 and
Tire Rotation 0352 for additional
information.
The rubber in tires ages over time.
This also applies to the spare tire,
if the vehicle has one, even if it is
never used. Multiple factors including
temperatures, loading conditions, and
inflation pressure maintenance affect
how fast aging takes place. GM
recommends that tires, including the
spare if equipped, be replaced after six years, regardless of tread wear. To
identify the age of a tire, use the tire
manufacture date, which is the last
four digits of the DOT Tire
Identification Number (TIN) molded
into one side of the tire sidewall. The
last four digits of the TIN indicate the
tire manufactured date. The first two
digits represent the week and the last
two digits, the year. For example, the
third week of the year 2020 would
have a 4-digit DOT date of 0320. Week
01 is the first full week (Sunday
through Saturday) of each year.
Vehicle Storage
Tires age when stored normally
mounted on a parked vehicle. Park a
vehicle that will be stored for at least
a month in a cool, dry, clean area
away from direct sunlight to slow
aging. This area should be free of
grease, gasoline, or other substances
that can deteriorate rubber.
Parking for an extended period can
cause flat spots on the tires that may
result in vibrations while driving.
When storing a vehicle for at least a
month, remove the tires or raise the
vehicle to reduce the weight from the
tires.
Buying New Tires
GM has developed and matched
specific tires for the vehicle. The
original equipment tires installed
were designed to meet General
Motors Tire Performance Criteria
Specification (TPC Spec) system
rating. When replacement tires are
needed, GM strongly recommends
buying tires with the same TPC
Spec rating.
GM's exclusive TPC Spec system
considers over a dozen critical
specifications that impact the
overall performance of the vehicle,
including brake system
performance, ride and handling,
traction control, and tire pressure
monitoring performance. GM's
TPC Spec number is molded onto
the tire's sidewall near the tire
size. If the tires have an all-season
tread design, the TPC Spec

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
VEHICLE CARE 357
graded 100. The relative
performance of tires depends
upon the actual conditions of
their use, however, and may
depart significantly from the norm
due to variations in driving habits,
service practices and differences
in road characteristics and
climate.
Traction
The traction grades, from highest
to lowest, are AA, A, B, and C.
Those grades represent the tire's
ability to stop on wet pavement as
measured under controlled
conditions on specified
government test surfaces of
asphalt and concrete. A tire
marked C may have poor traction
performance. Warning: The
traction grade assigned to this tire
is based on straight-ahead braking
traction tests, and does not
include acceleration, cornering,
hydroplaning, or peak traction
characteristics.Temperature
The temperature grades are A (the
highest), B, and C, representing
the tire's resistance to the
generation of heat and its ability
to dissipate heat when tested
under controlled conditions on a
specified indoor laboratory test
wheel. Sustained high temperature
can cause the material of the tire
to degenerate and reduce tire life,
and excessive temperature can
lead to sudden tire failure. The
grade C corresponds to a level of
performance which all passenger
car tires must meet under the
Federal Motor Safety Standard
No. 109. Grades B and A represent
higher levels of performance on
the laboratory test wheel than the
minimum required by law.
Warning: The temperature grade
for this tire is established for a tire
that is properly inflated and not
overloaded. Excessive speed,
underinflation, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.
Wheel Alignment and Tire
Balance
The tires and wheels were aligned and
balanced at the factory to provide the
longest tire life and best overall
performance. Adjustments to wheel
alignment and tire balancing are not
necessary on a regular basis. Consider
an alignment check if there is unusual
tire wear or the vehicle is significantly
pulling to one side or the other. Some
slight pull to the left or right,
depending on the crown of the road
and/or other road surface variations
such as troughs or ruts, is normal.
If the vehicle is vibrating when driving
on a smooth road, the tires and
wheels may need to be rebalanced.
See your dealer for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent,
cracked, or badly rusted or corroded.
If wheel nuts keep coming loose, the
wheel, wheel bolts, and wheel nuts

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
358 VEHICLE CARE
should be replaced. If the wheel leaks
air, replace it. Some aluminum wheels
can be repaired. See your dealer if any
of these conditions exist.
Your dealer will know the kind of
wheel that is needed.
Each new wheel should have the same
load-carrying capacity, diameter,
width, offset, and be mounted the
same way as the one it replaces.
Replace wheels, wheel bolts, wheel
nuts, or Tire Pressure Monitor System
(TPMS) sensors with new GM original
equipment parts.
{Warning
Using the wrong replacement
wheels, wheel bolts, or wheel nuts
can be dangerous. It could affect
the braking and handling of the
vehicle. Tires can lose air, and
cause loss of control, causing a
crash. Always use the correct wheel,
wheel bolts, and wheel nuts for
replacement.
Caution
The wrong wheel can also cause
problems with bearing life, brake
cooling, speedometer or odometer
calibration, headlamp aim, bumper
height, vehicle ground clearance,
and tire or tire chain clearance to
the body and chassis.
Used Replacement Wheels
{Warning
Replacing a wheel with a used one
is dangerous. How it has been used
or how far it has been driven may
be unknown. It could fail suddenly
and cause a crash. When replacing
wheels, use a new GM original
equipment wheel.
Tire Chains
{Warning
If the vehicle has 235/40R18 or
235/35R19 size tires, do not use tire
chains. There is not enough
clearance. Tire chains used on a
vehicle without the proper amount
of clearance can cause damage to
the brakes, suspension, or other
vehicle parts. The area damaged by
the tire chains could cause loss of
control and a crash. Use another
type of traction device only if its
manufacturer recommends it for
the vehicle's tire size combination
and road conditions. Follow that
manufacturer's instructions. To
avoid vehicle damage, drive slow
and readjust or remove the traction
device if it contacts the vehicle. Do
not spin the wheels. If traction
devices are used, install them on
the rear tires.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
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VEHICLE CARE 361
Read and follow all of the tire sealant
and compressor kit instructions.
The kit includes:
1. Sealant Canister Inlet Valve
2. Sealant/Air Hose
3. Base of Sealant Canister
4. Tire Sealant Canister
5. On/Off Button
6. Slot on Top of Compressor
7. Pressure Deflation Button
8. Pressure Gauge
9. Power Plug
10.Air Only Hose
Tire Sealant
Read and follow the safe handling
instructions on the label adhered to
the tire sealant canister (4).
Check the tire sealant expiration date
on the tire sealant canister. The tire
sealant canister (4) should be replaced
before its expiration date.
Replacement tire sealant canisters are
available at your local dealer.
There is only enough sealant to seal
one tire. After usage, the tire sealant
canister must be replaced.
Using the Tire Sealant and
Compressor Kit to Temporarily
Seal and Inflate a
Punctured Tire
When using the tire sealant and
compressor kit during cold
temperatures, warm the kit in a
heated environment for five minutes.
This will help to inflate the tire faster.
If a tire goes flat, avoid further tire
and wheel damage by driving slowly
to a level place. Turn on the hazard
warning flashers. SeeHazard Warning
Flashers 0129.
See If a Tire Goes Flat 0359 for other
important safety warnings.
Do not remove any objects that have
penetrated the tire.
1. Remove the tire sealant canister (4) and compressor from its storage
location. See Storing the Tire Sealant
and Compressor Kit 0366.
2. Remove the air only hose (10) and the power plug (9) from the bottom
of the compressor.
3. Place the compressor on the ground near the flat tire.