2023 CADILLAC CT4 tire size

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
422 Vehicle Care
and the original equipment
tire size and recommended
inflation pressure. See“Tire
and Loading Information
Label” under Vehicle Load
Limits 0255.
Tire Pressure
Tires need the correct
amount of air pressure to
operate effectively.
{Warning
Neither tire underinflation
nor overinflation is good.
Underinflated tires,
or tires that do not have
enough air, can result in:
.Tire overloading and
overheating, which
could lead to a blowout
.Premature or
irregular wear
.Poor handling
(Continued)
Warning (Continued)
.Reduced fuel economy
for internal combustion
engine vehicles
.Reduced range for
electric vehicles
Overinflated tires, or tires
that have too much air,
can result in:
.Unusual wear
.Poor handling
.Rough ride
.Needless damage from
road hazards
The Tire and Loading
Information label on the
vehicle indicates the
original equipment tires
and the correct cold tire
inflation pressures. The
recommended pressure is
the minimum air pressure
needed to support the vehicle's maximum load
carrying capacity. See
Vehicle Load Limits
0255.
How the vehicle is loaded
affects vehicle handling
and ride comfort. Never
load the vehicle with more
weight than it was
designed to carry.
When to Check
Check the pressure of the
tires once a month or more.
How to Check
Use a good quality
pocket-type gauge to
check tire pressure. Proper
tire inflation cannot be
determined by looking at
the tire. Check the tire
inflation pressure when the
tires are cold, meaning the
vehicle has not been driven
for at least three hours or
no more than 1.6 km (1 mi).

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 423
Remove the valve cap from
the tire valve stem. Press
the tire gauge firmly onto
the valve to get a pressure
measurement. If the cold
tire inflation pressure
matches the recommended
pressure on the Tire and
Loading Information label,
no further adjustment is
necessary. If the inflation
pressure is low, add air
until the recommended
pressure is reached. If the
inflation pressure is high,
press on the metal stem in
the center of the tire valve
to release air.
Recheck the tire pressure
with the tire gauge.
Put the valve caps back on
the valve stems to keep out
dirt and moisture. Use only
valve caps designed for the
vehicle by GM. TPMSsensors could be damaged
and would not be covered
by the vehicle warranty.
Tire Pressure for
High-Speed Operation
{Warning
Driving at high speeds,
160 km/h (100 mph) or
higher, puts additional strain
on tires. Sustained
high-speed driving causes
excessive heat buildup and
can cause sudden tire
failure. This could cause a
crash, and you or others
could be killed. Some
high-speed rated tires
require inflation pressure
adjustment for high-speed
operation. When speed
limits and road conditions
allow the vehicle to be
driven at high speeds, make
sure the tires are rated for
high-speed operation, are in
(Continued)
Warning (Continued)
excellent condition, and are
set to the correct cold tire
inflation pressure for the
vehicle load.
Vehicles with tire sizes listed
in the High Speed Operation
Inflation Pressures table
require inflation pressure
adjustment when driving the
vehicle at speeds of 160 km/h
(100 mph) or higher. Set the
cold tire inflation pressure to
the corresponding value in the
table for the tire size on the
vehicle.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
424 Vehicle Care
High Speed Operation Inflation Pressures
Tire Size Cold Inflation Pressure kPa (psi)
255/35ZR18 (94Y) 300 kPa (44 psi) Front
275/35ZR18 (99Y) 300 kPa (44 psi) Rear
225/45R17 91V 240 kPa (35 psi) Front
225/45R17 91V 280 kPa (41 psi) Rear
235/40R18 91V 250 kPa (36 psi) Front
235/40R18 91V 280 kPa (41 psi) Rear
235/40R18 95Y 300 kPa (44 psi) Front
235/40R18 95Y 340 kPa (49 psi) Rear
235/35R19 91V 270 kPa (39 psi) Front
235/35R19 91V 320 kPa (46 psi) Rear
Return the tires to the
recommended cold tire
inflation pressure when
high-speed driving has ended.
See Vehicle Load Limits0255
and
Tire Pressure 0422.Tire Pressure Monitor
System
The Tire Pressure Monitor
System (TPMS) uses radio and
sensor technology to check
tire pressure levels. The TPMS
sensors monitor the air
pressure in your tires and
transmit tire pressure
readings to a receiver located
in the vehicle. Each tire, including the spare
(if provided), should be
checked monthly when cold
and inflated to the inflation
pressure recommended by the
vehicle manufacturer on the
vehicle placard or tire inflation
pressure label. (If your vehicle
has tires of a different size
than the size indicated on the
vehicle placard or tire inflation
pressure label, you should

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
426 Vehicle Care
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 Limits0255.
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 pressure.
Using the DIC, tire pressure
levels can be viewed. For
additional information and
details about the DIC
operation and displays see
Driver Information Center
(DIC) (Base Level)
0129 or
Driver Information Center
(DIC) (Uplevel) 0132.
The low tire pressure warning
light may come on in cool
weather when the vehicle is
first started, and then turn off
as the vehicle is driven. This
could be an early indicator
that the air pressure is getting
low and needs to be inflated to
the proper pressure.
A Tire and Loading
Information label, attached to
your vehicle, shows the size of
the original equipment tires
and the correct inflation
pressure for the tires when
they are cold. See Vehicle
Load Limits 0255, for an
example of the Tire and Loading Information label and
its location. Also see Tire
Pressure
0422.
The TPMS can warn about a
low tire pressure condition but
it does not replace normal tire
maintenance. See Tire
Inspection 0429, Tire Rotation
0 429, and Tires 0413.Caution
Tire sealant materials are
not all the same.
A non-approved tire sealant
could damage the TPMS
sensors. TPMS sensor
damage caused by using an
incorrect tire sealant is not
covered by the vehicle
warranty. Always use only
the GM approved tire
sealant available through
your dealer or included in
the vehicle.
Factory-installed Tire Inflator
Kits use a GM-approved liquid
tire sealant. Using
non-approved tire sealants

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;
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Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
432 Vehicle Care
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 CriteriaSpecification (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 number will be
followed by MS for mud
and snow. See Tire
Sidewall Labeling
0417 for
additional information. GM recommends replacing
worn tires in complete sets
of four. Uniform tread
depth on all tires will help
to maintain the
performance of the vehicle.
Braking and handling
performance may be
adversely affected if all the
tires are not replaced at
the same time. If proper
rotation and maintenance
have been done, all four
tires should wear out at
about the same time.
However, if it is necessary
to replace only one axle set
of worn tires, place the
new tires on the rear axle.
See Tire Rotation
0429.{Warning
Tires could explode
during improper service.
Attempting to mount or
dismount a tire could
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