2020 CADILLAC XT5 tire size

286 VEHICLE CARE
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.
(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 three-digit
number indicates the tire section
width in millimeters from sidewall
to sidewall.
(3) Aspect Ratio
:A two-digit
number that indicates the tire
height-to-width measurements.
For example, if the tire size aspect
ratio is 60, as shown in item (3) of
the illustration, it would mean
that the tire's sidewall is
60 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).
Accessory Weight
:The combined
weight of optional accessories.
Some examples of optional
accessories are automatic
transmission, power windows,
power seats, and air conditioning.

VEHICLE CARE 289
Vehicle Capacity Weight:The
number of designated seating
positions multiplied by
68 kg (150 lb) plus the rated cargo
load. See Vehicle Load Limits 0170.
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 capacity
weight and the original equipment
tire size and recommended
inflation pressure. See “Tire and
Loading Information Label” under
Vehicle Load Limits 0170.
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.
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
0 170.
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. Do not
forget the compact spare, if the
vehicle has one. The cold compact
spare tire pressure should be at
420 kPa (60 psi). See Compact
Spare Tire 0315.

290 VEHICLE CARE
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).
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 and prevent leaks. 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
crash, and you or others could be
killed. Some high-speed rated tires
require inflation pressure
adjustment for high-speed
(Continued)
Warning (Continued)
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 235/65R18 or 235/55R20
size tires require inflation pressure
adjustment when driving the vehicle
at speeds of 160 km/h (100 mph) or
higher. Set the cold inflation pressure
to the maximum inflation pressure
shown on the tire sidewall, or 280 kPa
(41 psi), whichever is lower. Return
the tires to the recommended cold tire
inflation pressure when high-speed
driving has ended. See Vehicle Load
Limits 0170 and
Tire Pressure 0289.
The maximum load and inflation
pressure is molded on the tire
sidewall, in small letters, near the rim

VEHICLE CARE 291
flange. It will read something like this:
Maximum load 690 kg (1,521 lbs)
300 kPa (44 psi) Max. Press.
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 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 forapproximately 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
0 292.
See Radio Frequency Statement 0358.

292 VEHICLE CARE
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 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.
SeeVehicle Load Limits 0170. 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) 0124.
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 0170, for an
example of the Tire and Loading
Information label and its location.
Also see Tire Pressure 0289. The TPMS can warn about a low tire
pressure condition but it does not
replace normal tire maintenance. See
Tire Inspection
0295, Tire Rotation
0 296 and
Tires 0282.
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 0304
for information regarding the inflator
kit materials and instructions.

296 VEHICLE CARE
.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 every
12 000 km (7,500 mi). See
Maintenance Schedule0332.
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 0297 and
Wheel Replacement 0301.
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 0289 and
Vehicle Load Limits 0170.
Reset the Tire Pressure Monitor
System. See Tire Pressure Monitor
Operation 0292. Check that all wheel nuts are
properly tightened. See
“Wheel
Nut Torque ”under Capacities and
Specifications 0346, and
“Removing the Flat Tire and
Installing the Spare Tire ”under
Tire Changing 0310.
{Warning
Rust or dirt on a wheel, or on
the parts to which it is fastened,
can make wheel nuts become
loose after 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 a 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

298 VEHICLE CARE
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. SeeTire Sidewall
Labeling 0284.
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. See Tire
Rotation 0296. However, if it is
necessary to replace only one axle
set of worn tires, place the new
tires on the rear axle. 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.
{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,
tread patterns, or types on the
same axle may cause loss of
control of the vehicle, resulting
(Continued)
Warning (Continued)
in a crash or other vehicle
damage. Use the same size, load
range, and type of tires as the
original tires.
{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.
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.

VEHICLE CARE 299
Vehicles that have a tire pressure
monitoring system could give an
inaccurate low-pressure warning if
non-TPC Spec rated tires are
installed. SeeTire Pressure Monitor
System 0291.
The Tire and Loading Information
label indicates the original
equipment tires on the vehicle.
See Vehicle Load Limits 0170.
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.
{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 0297 and
Accessories and Modifications 0249.
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: