2005 CADILLAC STS tire size

Tire and Loading Information Label
A vehicle specic Tire and Loading Information label is
attached to the vehicle’s center pillar (B-pillar). With
the driver’s door open, you will nd the label attached
below the door lock post (striker). The tire and
loading information label shows the number of occupant
seating positions (A), and the maximum vehicle
capacity weight (B) in kilograms and pounds.The Tire and Loading Information label also shows the
tire size of the original equipment tires (C) and the
recommended cold tire ination pressures (D). For more
information on tires and ination seeTires on page 5-53
andInation - Tire Pressure on page 5-60.
There is also important loading information on the
Certication label. It tells you the Gross Vehicle Weight
Rating (GVWR) and the Gross Axle Weight Rating
(GAWR) for the front and rear axle; see “Certication
Label” later in this section.
Steps for Determining Correct Load Limit
1. Locate the statement “The combined weight of
occupants and cargo should never exceed
XXX pounds” on your vehicle placard.
2. Determine the combined weight of the driver and
passengers that will be riding in your vehicle.
3. Subtract the combined weight of the driver and
passengers from XXX kilograms or XXX pounds.
4. The resulting gure equals the available amount of
cargo and luggage load capacity. For example, if
the “XXX” amount equals 1400 lbs and there will be
ve 150 lb passengers in your vehicle, the amount
of available cargo and luggage load capacity is
650 lbs (1400−750 (5 x 150) = 650 lbs). Label Example
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Winter Tires
If you expect to drive on snow or ice covered roads
often, you may want to get winter tires for your vehicle.
All season tires provide good overall performance on
most surfaces but they may not offer the traction
you would like or the same level of performance as
winter tires on snow or ice covered roads.
See your dealer for details regarding winter tire
availability and proper tire selection. Also, seeBuying
New Tires on page 5-68
If you choose to use winter tires:
Use tires of the same brand and tread type on all
four wheel positions.
Use only radial ply tires of the same size, load
range, and speed rating as the original equipment
tires.
Winter tires with the same speed rating as your original
equipment tires may not be available for H, V, W
and ZR speed rated tires. If you choose winter tires with
a lower speed rating, never exceed the tire’s maximum
speed capability.
Tire Sidewall Labelling
Useful information about a tire is molded into its
sidewall. The examples below show a typical passenger
vehicle tire and a compact spare tire sidewall.
(A) Tire Size:The tire size is a combination of letters
and numbers used to dene a particular tire’s width,
height, aspect ratio, construction type and service
description. See the “Tire Size” illustration later in this
section for more detail.Passenger (P-Metric) Tire Example
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(B) 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.
(C) 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.
(D) Tire Identication Number (TIN):The letters and
numbers following 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.(E) Tire Ply Material:The type of cord and number of
plies in the sidewall and under the tread.
(F) Uniform Tire Quality Grading (UTQG):Tire
manufacturers are required to grade tires based on three
performance factors: treadwear, traction and
temperature resistance. For more information see
Uniform Tire Quality Grading on page 5-70.
(G) Maximum Cold Ination Load Limit:Maximum
load that can be carried and the maximum pressure
needed to support that load.
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(A) Temporary Use Only:The compact spare tire or
temporary use tire has a tread life of approximately
3,000 miles (5 000 km) and should not be driven
at speeds over 65 mph (105 km/h). The compact spare
tire is for emergency use when a regular road tire
has lost air and gone at. If your vehicle has a compact
spare tire, seeCompact Spare Tire on page 5-84
andIf a Tire Goes Flat on page 5-74.(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 see
Ination - Tire Pressure on page 5-60.
(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. Compact Spare Tire Example
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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.(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.
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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. SeeUniform
Tire Quality Grading on page 5-70.
Vehicle Capacity Weight:The number of designated
seating positions multiplied by 150 lbs (68 kg) plus
the rated cargo load. SeeLoading Your Vehicle
on page 4-30.
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
ination pressure. See “Tire and Loading Information
Label” underLoading Your Vehicle on page 4-30.Ination - Tire Pressure
Tires need the correct amount of air pressure to operate
effectively.
Notice:Do not let anyone tell you that
under-ination or over-ination is all right. It is not.
If your tires do not have enough air (under-ination),
you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air (over-ination), you
can get the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road hazards
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If a low tire pressure condition is detected, the TPM
system will display the CHECK TIRE PRESSURE
warning message on the Driver Information Center (DIC)
and, at the same time, illuminate the low tire pressure
warning symbol, on the instrument panel cluster.
When the tire pressure
monitoring system warning
light is lit, one or more
of your tires is signicantly
under-inated.
You should stop and check your tires as soon as
possible, and inate them to the proper pressure as
indicated on the vehicle’s tire information placard.
Driving on a signicantly under-inated tire causes the
tire to overheat and can lead to tire failure.
Under-ination also reduces fuel efficiency and tire tread
life, and may affect the vehicle’s handling and stopping
ability. Each tire, including the spare, should be
checked monthly when cold and set to the
recommended ination pressure as specied in the
vehicle placard and owner’s manual.The Tire and Loading Information Label (your vehicle’s
tire information placard) shows the size of your vehicle’s
original tires and the recommended cold ination
pressure for your vehicle’s tire. SeeInation - Tire
Pressure on page 5-60. For the location of the tire and
loading information label, seeLoading Your Vehicle on
page 4-30.
Your vehicle’s TPM system can alert you about a low
tire pressure condition but it does not replace normal tire
maintenance. SeeTire Inspection and Rotation on
page 5-65andTires on page 5-53.
Notice:Do not use a tire sealant if your vehicle is
equipped with Tire Pressure Monitors. The liquid
sealant can damage the tire pressure monitor
sensors.
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11. Set all four tires to the recommended air pressure
level as indicated on the tire and loading information
label.
12. Put the valve caps back on the valve stems.
The spare tire does not have a TPM sensor. If you
replace one of the road tires with the spare, the
SERVICE TIRE MONITOR message will be displayed
on the DIC screen. This message should go off
once you re-install the road tire containing the TPM
sensor. The SERVICE TIRE MONITOR message is also
displayed when the TPM system is malfunctioning.
One or more missing or inoperable TPM sensors will
cause the SERVICE TIRE MONITOR message to
be displayed. See your GM dealer for service.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation.This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
Tire Inspection and Rotation
Tire rotation is not recommended if your vehicle has the
following performance tire combinations:
P235/50R17 size tires on the front wheels and
P255/45R17 size tires on the rear wheels.
P235/50R18 size tires on the front wheels and
P255/45R18 size tires on the rear wheels.
Different tire sizes front to rear should not be rotated.
Each tire and wheel should be used only in the position
it is in.
Tire rotation is recommended if your vehicle is equipped
with P235/50R17 size tires on all four wheel positions
or 255/45ZR18 size tires on all four wheel positions.
These tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km)
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