2023 CADILLAC XT4 tire size

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16412876) - 2023 - CRC - 3/25/22
Vehicle Care 367
Caution (Continued)
on the tires. Always inspect
tires before use. See Tire
Inspection0380.
Tire Sidewall Labeling
Useful information about a
tire is molded into its
sidewall. The examples
show a typical passenger
vehicle tire and a compact
spare tire sidewall.
Passenger Tire Example
(1) Tire Size:The tire size
is a combination of letters
and numbers used to
define a particular tire's
width, height, aspect ratio,
construction type, and
service description. See the
“Tire Size” illustration in
this section.
(2) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed
to GM's specific tire
performance criteria have a
TPC specification code
molded onto the sidewall.
GM's TPC specifications
meet or exceed all federal
safety guidelines.
(3) DOT (Department of
Transportation)
:The
Department of
Transportation (DOT) code
indicates that the tire is in
compliance with the U.S. Department of
Transportation Motor
Vehicle Safety Standards.
DOT Tire Date of
Manufacture
: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.
(4) Tire Identification
Number (TIN)
:The letters
and numbers following the
DOT (Department of
Transportation) code are
the Tire Identification
Number (TIN). The TIN
shows the manufacturer
and plant code, tire size,

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16412876) - 2023 - CRC - 3/25/22
368 Vehicle Care
and date the tire was
manufactured. The TIN is
molded onto both sides of
the tire, although only one
side may have the date of
manufacture.
(5) Tire Ply Material
:The
type of cord and number of
plies in the sidewall and
under the tread.
(6) Uniform Tire Quality
Grading (UTQG)
:Tire
manufacturers are required
to grade tires based on
three performance factors:
tread wear, traction, and
temperature resistance.
For more information see
Uniform Tire Quality
Grading 0385.
(7) Maximum Cold
Inflation Load Limit
:
Maximum load that can be
carried and the maximum
pressure needed to
support that load.
Compact Spare Tire Example
(1) Tire Ply Material:The
type of cord and number of
plies in the sidewall and
under the tread.
(2) Temporary Use Only
:
The compact spare tire or
temporary use tire should
not be driven at speeds
over 80 km/h (50 mph). The
compact spare tire is for
emergency use when a
regular road tire has lost
air and gone flat. If the
vehicle has a compact spare tire, see Compact
Spare Tire
0404 and
If a Tire Goes Flat 0389.
(3) Tire Identification
Number (TIN)
:The letters
and numbers following the
DOT (Department of
Transportation) code are
the Tire Identification
Number (TIN). The TIN
shows the manufacturer
and plant code, tire size,
and date the tire was
manufactured. The TIN is
molded onto both sides of
the tire, although only one
side may have the date of
manufacture.
(4) Maximum Cold
Inflation Load Limit
:
Maximum load that can be
carried and the maximum
pressure needed to
support that load.

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(5) Tire Inflation:The
temporary use tire or
compact spare tire should
be inflated to 420 kPa
(60 psi). For more
information on tire
pressure and inflation see
Tire Pressure 0372.
(6) Tire Size
:A
combination of letters and
numbers define a tire's
width, height, aspect ratio,
construction type, and
service description. The
letter “T”as the first
character in the tire size
means the tire is for
temporary use only.
(7) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed
to GM's specific tire
performance criteria have a
TPC specification code
molded onto the sidewall. GM's TPC specifications
meet or exceed all federal
safety guidelines.
Tire Designations
Tire Size
The example shows a
typical passenger vehicle
tire size.
Passenger (P-Metric) Tire
(1) Passenger (P-Metric)
Tire
:The United States
version of a metric tire
sizing system. The letter
"P" as the first character in
the tire size means a
passenger vehicle tire
engineered to standards
set by the U.S. Tire and Rim
Association. (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.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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372 Vehicle Care
Speed Rating:An
alphanumeric code
assigned to a tire indicating
the maximum speed at
which a tire can operate.
Traction
:The friction
between the tire and the
road surface. The amount
of grip provided.
Tread
:The portion of a
tire that comes into
contact with the road.
Treadwear Indicators
:
Narrow bands, sometimes
called wear bars, that show
across the tread of a tire
when only 1.6 mm (1/16 in)
of tread remains. See
When It Is Time for New
Tires 0382.
UTQGS (Uniform Tire
Quality Grading
Standards)
:A tire
information system that
provides consumers with
ratings for a tire's traction, temperature, and
treadwear. Ratings are
determined by tire
manufacturers using
government testing
procedures. The ratings
are molded into the
sidewall of the tire. See
Uniform Tire Quality
Grading
0385.
Vehicle Capacity Weight
:
The number of designated
seating positions multiplied
by 68 kg (150 lbs) plus the
rated cargo load. See
Vehicle Load Limits 0242.
Vehicle Maximum Load on
the Tire
:Load on an
individual tire due to curb
weight, accessory weight,
occupant weight, and cargo
weight.
Vehicle Placard
:A label
permanently attached to a
vehicle showing the
vehicle's capacity weight and the original equipment
tire size and recommended
inflation pressure. See
“Tire
and Loading Information
Label” under Vehicle Load
Limits 0242.
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)

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16412876) - 2023 - CRC - 3/25/22
374 Vehicle Care
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. TPMS
sensors 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(Continued)
Warning (Continued)
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
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 XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 375
High Speed Operation Inflation Pressures
Tire Size Cold Inflation Pressure kPa (psi)
235/55R18 260 kPa (38 psi)
245/45R20 260 kPa (38 psi)
Return the tires to the
recommended cold tire
inflation pressure when
high-speed driving has ended.
See Vehicle Load Limits 0242
and Tire Pressure 0372.
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
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 to
maintain correct tire pressure,
even if under-inflation has not

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Vehicle Care 377
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)0136.
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 0242, for an
example of the Tire and
Loading Information label and
its location. Also see Tire
Pressure 0372. The TPMS can warn about a
low tire pressure condition but
it does not replace normal tire
maintenance. See Tire
Inspection
0380, Tire
Rotation 0381, and Tires
0 364.
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
could damage the TPMS sensors. See Tire Sealant and
Compressor Kit
0390 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

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 381
.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
0425. Tires are rotated to
achieve a more 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
0382
and Wheel Replacement
0 387.
Use this rotation pattern
when rotating the tires.
Do not include the compact
spare tire in the tire
rotation.
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 0372
and Vehicle Load Limits
0 242.