2023 CADILLAC CT4 wheel

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 419
(2) Tire Width:The 3-digit
number indicates the tire
section width in millimeters
from sidewall to sidewall.
(3) Aspect Ratio
:A 2-digit
number that indicates the
tire height-to-width
measurements. For
example, if the tire size
aspect ratio is 75, as
shown in item (3) of the
illustration, it would mean
that the tire's sidewall is
75 percent as high as it
is wide.
(4) Construction Code
:A
letter code is used to
indicate the type of ply
construction in the tire. The
letter "R" means radial ply
construction; the letter "D"
means diagonal or bias ply
construction.
(5) Rim Diameter
:
Diameter of the wheel in
inches. (6) Service Description
:
These characters
represent the load index
and speed rating of the
tire. The load index
represents the load
carrying capacity a tire is
certified to carry. The
speed rating is the
maximum speed a tire is
certified to carry a load.
Tire Terminology and
Definitions
Air Pressure:The amount
of air inside the tire
pressing outward on each
square inch of the tire. Air
pressure is expressed
in kPa (kilopascal) or psi
(pounds per square inch).
Aspect Ratio
:The
relationship of a tire's
height to its width. Belt
:A rubber coated layer
of cords that is located
between the plies and the
tread. Cords may be made
from steel or other
reinforcing materials.
Bead
:The tire bead
contains steel wires
wrapped by steel cords
that hold the tire onto
the rim.
Bias Ply Tire
:A pneumatic
tire in which the plies are
laid at alternate angles less
than 90 degrees to the
centerline of the tread.
Cold Tire Pressure
:The
amount of air pressure in a
tire, measured in kPa
(kilopascal) or psi (pounds
per square inch) before a
tire has built up heat from
driving. See Tire Pressure
0 422.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 425
determine the proper tire
inflation pressure for those
tires.)
As an added safety feature,
your vehicle has been
equipped with a tire pressure
monitoring system (TPMS)
that illuminates a low tire
pressure telltale when one or
more of your tires is
significantly under-inflated.
Accordingly, when the low tire
pressure telltale illuminates,
you should stop and check
your tires as 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
energy 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 tomaintain 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
0425.
See Radio Frequency
Statement 0494.
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

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 427
could damage the TPMS
sensors. See Tire Sealant and
Compressor Kit0439 for
information regarding the
inflator kit materials and
instructions.
TPMS Malfunction Light
and Message
The TPMS will not function
properly if one or more of the
TPMS sensors are missing or
inoperable. When the system
detects a malfunction, the low
tire pressure warning light
flashes for about one minute
and then stays on for the
remainder of the ignition cycle.
A DIC warning message also
displays. The malfunction light
and DIC warning message
come on at each ignition cycle
until the problem is corrected.
Some of the conditions that
can cause these to come
on are:
.One of the road tires has
been replaced with the
spare tire. The spare tire
does not have a TPMS sensor. The malfunction light
and DIC message should go
off after the road tire is
replaced and the sensor
matching process is
performed successfully. See
“TPMS Sensor Matching
Process”
later in this section.
.The TPMS sensor matching
process was not done or not
completed successfully after
rotating the tires. The
malfunction light and the DIC
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. See
Buying New Tires
0432.
.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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 429
tire fill alert feature is not
working, use a tire pressure
gauge.
TPMS Sensor Matching
Process—Auto Learn
Function
Each TPMS sensor has a
unique identification code. The
identification code needs to be
matched to a new tire/wheel
position after rotating the
tires or replacing one or more
of the TPMS sensors. When a
tire is installed, the vehicle
must be stationary for about
20 minutes before the system
recalculates. The following
relearn process takes up to
10 minutes, driving at a
minimum speed of 20 km/h
(12 mph). A dash (-) or pressure
value will display in the DIC.
See Driver Information Center
(DIC) (Base Level) 0129 or
Driver Information Center
(DIC) (Uplevel) 0132. A warning
message displays in the DIC if
a problem occurs during the
relearn process.
Tire Inspection
We recommend that the
tires, including the spare
tire, if the vehicle has one,
be inspected for signs of
wear or damage at least
once a month.
Replace the tire if:
.The indicators at three or
more places around the
tire can be seen.
.There is cord or fabric
showing through the
tire's rubber.
.The tread or sidewall is
cracked, cut, or snagged
deep enough to show
cord or fabric.
.The tire has a bump,
bulge, or split.
.The tire has a puncture,
cut, or other damage that
cannot be repaired well
because of the size or
location of the damage.
Tire Rotation
Tires should be rotated
according to the interval
specified in the
Maintenance Schedule. See
Maintenance Schedule
0 469.
Tires are rotated to
achieve a uniform wear for
all tires. The first rotation is
the most important.
Anytime unusual wear is
noticed, rotate the tires as
soon as possible, check for
proper tire inflation
pressure, and check for
damaged tires or wheels.
If the unusual wear
continues after the
rotation, check the wheel
alignment. See When It Is
Time for New Tires 0431
and
Wheel Replacement 0436.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
430 Vehicle Care
Use this rotation pattern if
the vehicle has different
size tires on the front
and rear.
Different tire sizes should
not be rotated front
to rear.Use this rotation pattern
when rotating tires of the
same size installed on all
four wheel positions.
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 Pressure0422
and
Vehicle Load Limits 0255. Reset the Tire Pressure
Monitor System. See Tire
Pressure Monitor
Operation
0425.
Check that all wheel nuts
are properly tightened. See
“Wheel Nut Torque” under
Capacities and
Specifications 0480.
{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;
(Continued)

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 431
Warning (Continued)
however, use a scraper
or wire brush later to
remove all rust or dirt.
Lightly coat the center of
the wheel hub 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.
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. See
Tire Inspection 0429 and
Tire Rotation 0429. 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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 433
Warning (Continued)
cause injury or death.
Only your dealer or
authorized tire service
center should mount or
dismount the tires.
{Warning
Mixing tires of different
sizes (other than those
originally installed on the
vehicle), brands, tread
patterns, or types may
cause loss of vehicle
control, resulting in a
crash or other vehicle
damage. Use the correct
size, brand, and type of
tire on all wheels.
{Warning
Using bias-ply tires on
the vehicle may cause the
wheel rim flanges to
develop cracks after
many miles of driving.
A tire and/or wheel could
fail suddenly and cause a
crash. Use only radial-ply
tires with the wheels on
the vehicle.
Winter tires with the same
speed rating as the original
equipment tires may not be
available for H, V, W, Y and
ZR speed rated tires. Never
exceed the winter tires’
maximum speed capability
when using winter tires
with a lower speed rating.
If the vehicle tires must be
replaced with a tire that
does not have a TPC Spec
number, make sure they
are the same size, load range, speed rating, and
construction (radial) as the
original tires.
The Tire and Loading
Information label indicates
the original equipment tires
on the vehicle. See Vehicle
Load Limits
0255.
Different Size Tires
and Wheels
If wheels or tires are installed
that are a different size than
the original equipment wheels
and tires, vehicle performance,
including its braking, ride and
handling characteristics,
stability, and resistance to
rollover may be affected. If the
vehicle has electronic systems
such as antilock brakes,
rollover airbags, traction
control, electronic stability
control, or All-Wheel Drive, the
performance of these systems
can also be affected.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
434 Vehicle Care
{Warning
If different sized wheels are
used, there may not be an
acceptable level of
performance and safety if
tires not recommended for
those wheels are selected.
This increases the chance of
a crash and serious injury.
Only use GM specific wheel
and tire systems developed
for the vehicle, and have
them properly installed by a
GM certified technician.
See Buying New Tires 0432
and
Accessories and Modifications
0 370.
Uniform Tire Quality
Grading
The following information
relates to the system
developed by the United
States National Highway
Traffic Safety Administration (NHTSA),
which grades tires by
treadwear, traction, and
temperature performance.
This applies only to
vehicles sold in the United
States. The grades are
molded on the sidewalls of
most passenger car tires.
The Uniform Tire Quality
Grading (UTQG) system
does not apply to deep
tread, winter tires, compact
spare tires, tires with
nominal rim diameters of
10 to 12 inches
(25 to 30 cm), or to some
limited-production tires.
While the tires available on
General Motors passenger
cars and light trucks may
vary with respect to these
grades, they must also
conform to federal safety
requirements and
additional General Motors
Tire Performance Criteria
(TPC) standards.
Quality grades can be
found where applicable on
the tire sidewall between
tread shoulder and
maximum section width.
For example:
Treadwear 200 Traction AA
Temperature A
All Passenger Car Tires
Must Conform to Federal
Safety Requirements In
Addition To These Grades.
Treadwear
The treadwear grade is a
comparative rating based
on the wear rate of the tire
when tested under
controlled conditions on a
specified government test
course. For example, a tire
graded 150 would wear one
and one-half (1½) times as