2008 CADILLAC STS tire type

(B) Tire Ply Material:The type of cord and
number of plies in the sidewall and under
the tread.
(C) Tire Identication Number (TIN)
:The letters
and numbers following the DOT (Department of
Transportation) code is the Tire Identication
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.
(D) Maximum Cold Ination Load Limit
:Maximum load that can be carried and the
maximum pressure needed to support that load.
(E) Tire Ination
:The temporary use tire or
compact spare tire should be inated to 60 psi
(420 kPa). For more information on tire pressure
and ination seeInflation - Tire Pressure on
page 5-66.
(F) Tire Size
:A combination of letters and
numbers dene a tire’s width, height, aspect ratio,
construction type, and service description. The
letter T as the rst character in the tire size means
the tire is for temporary use only.(G) TPC Spec (Tire Performance Criteria
Specication)
:Original equipment tires designed
to GM’s specic tire performance criteria have
a TPC specication code molded onto the sidewall.
GM’s TPC specications meet or exceed all
federal safety guidelines.
Tire Size
The following illustration shows an example of a
typical passenger vehicle tire size.
(A) Passenger (P-Metric) Tire
:The United States
version of a metric tire sizing system. The letter
P as the rst character in the tire size means
a passenger vehicle tire engineered to standards
set by the U.S. Tire and Rim Association.
(B) Tire Width
:The three-digit number indicates
the tire section width in millimeters from sidewall
to sidewall.
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(C) 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 C of the illustration, it would
mean that the tire’s sidewall is 60 percent as
high as it is wide.
(D) 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; and the letter B means
belted-bias ply construction.
(E) Rim Diameter
:Diameter of the wheel in
inches.
(F) Service Description
:These characters
represent the load range and speed rating of the
tire. The load index represents the load carry
capacity a tire is certied to carry. The load index
can range from 1 to 279. The speed rating is
the maximum speed a tire is certied to carry a
load. Speed ratings range from A to Z.
Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of
the tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
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.
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A vehicle specic Tire and Loading Information
label is attached to your vehicle. This label
lists your vehicle’s original equipment tires and
shows the correct ination pressures for your tires
when they are cold. The recommended cold
tire ination pressure, shown on the label, is the
minimum amount of air pressure needed to
support your vehicle’s maximum load carrying
capacity.
For additional information regarding how much
weight your vehicle can carry, and an example
of the tire and loading information label, see
Loading Your Vehicle on page 4-26. How you load
your vehicle affects vehicle handling and ride
comfort. Never load your vehicle with more weight
than it was designed to carry.
When to Check
Check your tires once a month or more. Do not
forget to check the compact spare tire, if your
vehicle has one. The compact spare should be
at 60 psi (420 kPa). For additional information
regarding the compact spare tire, seeCompact
Spare Tire on page 5-106.
How to Check
Use a good quality pocket-type gage to check
tire pressure. You cannot tell if your tires are
properly inated simply by looking at them. Radial
tires may look properly inated even when they
are underinated. Check the tire’s ination
pressure when the tires are cold. Cold means your
vehicle has been sitting for at least three hours
or driven no more than 1 mile (1.6 km).
Remove the valve cap from the tire valve stem.
Press the tire gage rmly onto the valve to
get a pressure measurement. If the cold tire
ination pressure matches the recommended
pressure on the Tire and Loading Information
label, no further adjustment is necessary. If the
ination pressure is low, add air until you reach the
recommended amount.
If you overll the tire, release air by pushing on
the metal stem in the center of the tire valve.
Re-check the tire pressure with the tire gage.
Be sure to put the valve caps back on the valve
stems. They help prevent leaks by keeping out dirt
and moisture.
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{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
(other than those originally installed on your
vehicle), brands, or types (radial and
bias-belted tires), the vehicle may not handle
properly, and you could have a crash. Using
tires of different sizes (other than those
originally installed on your vehicle), brands, or
types may also cause damage to your vehicle.
Be sure to use the correct size, brand, and
type of tires on all wheels. It is all right to drive
with your vehicle’s compact spare temporarily,
it was developed for use on your vehicle. See
Compact Spare Tire on page 5-106.
{CAUTION:
If you use bias-ply tires on your vehicle,
the wheel rim anges could develop
cracks after many miles of driving. A tire
and/or wheel could fail suddenly, causing
a crash. Use only radial-ply tires with the
wheels on your vehicle.
If you must replace your vehicle’s tires with those that
do not have a TPC Spec number, make sure they
are the same size, load range, speed rating, and
construction type (radial and bias-belted tires) as your
vehicle’s original tires.
Vehicles that have a tire pressure monitoring system
could give an inaccurate low-pressure warning if
non-TPC Spec rated tires are installed on it. Non-TPC
Spec rated tires may give a low-pressure warning that is
higher or lower than the proper warning level you
would get with TPC Spec rated tires. SeeTire Pressure
Monitor System on page 5-68.
5-77

Uniform Tire Quality Grading
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
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-type
snow tires, space-saver, or temporary use
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.
Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specied
government test course. For example, a tire
graded 150 would wear one and a half (1.5) times
as well on the government course as a tire
graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart signicantly from
the norm due to variations in driving habits, service
practices, and differences in road characteristics
and climate.
Traction – AA, A, B, C
The traction grades, from highest to lowest, are
AA, A, B, and C. Those grades represent the tire’s
ability to stop on wet pavement as measured
under controlled conditions on specied
government test surfaces of asphalt and concrete.
A tire marked C may have poor traction
performance.
Warning
:The traction grade assigned to
this tire is based on straight-ahead braking
traction tests, and does not include
acceleration, cornering, hydroplaning,
or peak traction characteristics.
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Tire Chains
{CAUTION:
If your vehicle has P255/45R17, P235/50ZR18,
P255/45ZR18, P275/40R19, or 255/45ZR18 size
tires, do not use tire chains, as there is not
enough clearance.
Tire chains used on a vehicle without the
proper amount of clearance can cause damage
to the brakes, suspension, or other vehicle
parts. The area damaged by the tire chains
could cause you to lose control of your vehicle
and you or others may be injured in a crash.
CAUTION: (Continued)
CAUTION: (Continued)
Use another type of traction device only if its
manufacturer recommends it for use on your
vehicle and tire size combination and road
conditions. Follow that manufacturer’s
instructions. To help avoid damage to your
vehicle, drive slowly, readjust, or remove the
device if it is contacting your vehicle, and do
not spin your vehicle’s wheels.
If you do nd traction devices that will t,
install them on the rear tires only.
Notice:If your vehicle has P235/50R17 size tires,
use tire chains only where legal and only when you
must. Use only SAE Class S-type chains that are
the proper size for your tires. Install them on the rear
tires and tighten them as tightly as possible with
the ends securely fastened. Drive slowly and follow
the chain manufacturer’s instructions. If you can
hear the chains contacting your vehicle, stop
and retighten them. If the contact continues, slow
down until it stops. Driving too fast or spinning the
wheels with chains on will damage your vehicle.
5-82

Emergency Road Service is performed on site for the
following situations:
Fuel Delivery:Delivery of enough fuel for the vehicle
to get to the nearest service station (approximately
$5 in Canada). In Canada, for safety reasons,
propane and other alternative fuels will not be
provided through this service.
Lock-out Service:Lock-out service will be covered
at no charge if you are unable to gain entry into your
vehicle. A remote unlock may be available if you
have an active OnStar
®subscription. To ensure
security, the driver must present personal
identication before lock-out service is provided.
In Canada, the vehicle registration is also required.
Emergency Tow From a Public Roadway or
Highway:Tow to the nearest dealership for warranty
service or in the event of a vehicle-disabling crash.
Winch-out assistance is provided when the vehicle is
mired in sand, mud, or snow.
Flat Tire Change:Installation of a spare tire in good
condition, when equipped and properly inated, is
covered at no charge. The customer is responsible
for the repair or replacement of the tire if not covered
by a warrantable failure.
Jump Start:A battery jump start is covered at no
charge if the vehicle does not start.
Trip Routing Service:Upon request, Cadillac
Roadside Service will send you detailed, computer
personalized maps, highlighting your choice of either
the most direct route or the most scenic route to your
destination, anywhere in North America, along with
helpful travel information pertaining to your trip.
Please allow three weeks before your planned
departure date. In Canada, trip routing requests will
be limited to six per calendar year.
Trip Interruption Benets and Assistance:If your
trip is interrupted due to a warranty failure, incidental
expenses may be reimbursed during the 60 months/
100,000 miles (160 000 km) warranty period. Items
covered are hotel, meals, and rental car.
Alternative Service (Canada only):There may be
times when Roadside Service cannot provide timely
assistance. Your advisor may authorize you to
secure local emergency road service, and you will be
reimbursed up to $100 upon submission of the
original receipt to Cadillac Roadside Service
®.
Cadillac and General Motors of Canada Limited reserve
the right to limit services or reimbursement to an
owner or driver when, in their sole discretion, the claims
become excessive in frequency or type of occurrence.
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