2023 CADILLAC XT6 tire size

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-16405819) -
2023 - CRC - 3/22/22
Vehicle Care 405
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. (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.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-16405819) -
2023 - CRC - 3/22/22
408 Vehicle Care
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 0421.
Vehicle Capacity Weight
:
The number of designated
seating positions multiplied
by 68 kg (150 lbs) plus the
rated cargo load. See
Vehicle Load Limits 0252. 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 0252.
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
.Reduced fuel economy
for internal combustion
engine vehicles
.Reduced range for
electric vehicles
(Continued)

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-16405819) -
2023 - CRC - 3/22/22
410 Vehicle Care
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
on tires. Sustained
high-speed driving causes
excessive heat buildup and
can cause sudden tire
failure. This could cause a(Continued)
Warning (Continued)
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 XT6 Owner Manual (GMNA-Localizing-U.S./Canada-16405819) -
2023 - CRC - 3/22/22
Vehicle Care 411
High Speed Operation Inflation Pressures
Tire Size Cold Inflation Pressure kPa (psi)
235/65R18 300 kPa (44 psi)
235/55R20 300 kPa (44 psi) 265/45R21 300 kPa (44 psi)
Return the tires to the
recommended cold tire
inflation pressure when
high-speed driving has ended.
See Vehicle Load Limits 0252
and Tire Pressure 0408.
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 tirepressure 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

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-16405819) -
2023 - CRC - 3/22/22
Vehicle Care 413
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)0144.
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 0252, for an
example of the Tire and
Loading Information label and
its location. Also see Tire
Pressure 0408. The TPMS can warn about a
low tire pressure condition but
it does not replace normal tire
maintenance. See Tire
Inspection
0416, Tire Rotation
0 417, and Tires 0400.
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.
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

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-16405819) -
2023 - CRC - 3/22/22
Vehicle Care 417
.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
0454.
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
0418
and Wheel Replacement
0 423.
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
0408
and Vehicle Load Limits
0 252.
Reset the Tire Pressure
Monitor System. See Tire
Pressure Monitor
Operation 0412.
Check that all wheel nuts
are properly tightened.
See “Wheel Nut Torque”
under Capacities and
Specifications 0463, and
“Removing the Flat Tire and
Installing the Spare Tire”
under Tire Changing 0426.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-16405819) -
2023 - CRC - 3/22/22
Vehicle Care 419
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 freeof 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 number will be
followed by MS for mud
and snow. See Tire
Sidewall Labeling
0402 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

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-16405819) -
2023 - CRC - 3/22/22
420 Vehicle Care
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 Rotation0417.
{Warning
Tires could explode
during improper service.
Attempting to mount or
dismount a tire could
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
0252.