
Black plate (54,1)Cadillac STS Owner Manual - 2011
(B) Tire Ply Material:The type of cord and
number of plies in the sidewall and under the
tread.
(C) Tire Identification Number (TIN)
:The letters
and numbers following the DOT (Department of
Transportation) code is 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.
(D) Maximum Cold Inflation Load Limit
:
Maximum load that can be carried and the
maximum pressure needed to support that load.
(E) Tire Inflation
:The temporary use tire or
compact spare tire should be inflated to 60 psi
(420 kPa). For more information on tire pressure
and inflation see Inflation - Tire Pressure
on
page 6‑58
.
(F) 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. (G) 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 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 first character in the tire size means a
passenger vehicle tire engineered to standards
set by the U.S. Tire and Rim Association.
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Cold Tire Pressure:The amount of air pressure
in a tire, measured in pounds per square inch (psi)
or kilopascals (kPa) before a tire has built up heat
from driving. See Inflation - Tire Pressure
on
page 6‑58
.
Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant, but
without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identification Number (TIN), an
alphanumeric designator which can also identify
the tire manufacturer, production plant, brand, and
date of production.
GVWR
:Gross Vehicle Weight Rating. See
Loading the Vehicle
on page 5‑23.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. See Loading the Vehicle
on page 5‑23.
GAWR RR
:Gross Axle Weight Rating for the rear
axle. See Loading the Vehicle
on page 5‑23. Intended Outboard Sidewall
:The side of an
asymmetrical tire, that must always face outward
when mounted on a vehicle.
Kilopascal (kPa)
:The metric unit for air pressure.
Light Truck (LT‐Metric) Tire
:A tire used on light
duty trucks and some multipurpose passenger
vehicles.
Load Index
:An assigned number ranging
from 1 to 279 that corresponds to the load
carrying capacity of a tire.
Maximum Inflation Pressure
:The maximum air
pressure to which a cold tire can be inflated. The
maximum air pressure is molded onto the
sidewall.
Maximum Load Rating
:The load rating for a tire
at the maximum permissible inflation pressure for
that tire.
Maximum Loaded Vehicle Weight
:The sum of
curb weight, accessory weight, vehicle capacity
weight, and production options weight.
Normal Occupant Weight
:The number of
occupants a vehicle is designed to seat multiplied
by 150 lbs (68 kg). See Loading the Vehicle
on
page 5‑23
.
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Occupant Distribution:Designated seating
positions.
Outward Facing Sidewall
:The side of an
asymmetrical tire that has a particular side that
faces outward when mounted on a vehicle. The
side of the tire that contains a whitewall, bears
white lettering, or bears manufacturer, brand,
and/or model name molding that is higher or
deeper than the same moldings on the other
sidewall of the tire.
Passenger (P-Metric) Tire
:A tire used on
passenger cars and some light duty trucks and
multipurpose vehicles.
Recommended Inflation Pressure
:Vehicle
manufacturer's recommended tire inflation
pressure as shown on the tire placard. See
Inflation - Tire Pressure
on page 6‑58and Loading
the Vehicle
on page 5‑23.
Radial Ply Tire
:A pneumatic tire in which the ply
cords that extend to the beads are laid at
90 degrees to the centerline of the tread.
Rim
:A metal support for a tire and upon which
the tire beads are seated.
Sidewall
:The portion of a tire between the tread
and the bead. 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 1/16 inch (1.6 mm) of tread
remains. See When It Is Time for New Tires
on
page 6‑67
.
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
on page 6‑71.
Vehicle Capacity Weight
:The number of
designated seating positions multiplied by
150 lbs (68 kg) plus the rated cargo load.
See Loading the Vehicle
on page 5‑23.
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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” underLoading the
Vehicle
on page 5‑23.
Inflation - Tire Pressure
Tires need the correct amount of air pressure to
operate effectively.
Notice:Do not let anyone tell you that
under‐inflation or over‐inflation is all right.
It is not. If your tires do not have enough air
(under‐inflation), you can get the following:
.Tire overloading and over-heating which
could lead to a blowout.
.Premature or irregular wear.
.Poor handling.
.Reduced fuel economy. If your tires have too much air (over‐inflation),
you can get the following:
.Unusual wear.
.Poor handling.
.Rough ride.
.Needless damage from road hazards.
A vehicle specific Tire and Loading Information
label is attached to your vehicle. This label lists
your vehicle's original equipment tires and shows
the correct inflation pressures for your tires when
they are cold. The recommended cold tire inflation
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
the Vehicle
on page 5‑23. How you load your
vehicle affects vehicle handling and ride comfort.
Never load your vehicle with more weight than it
was designed to carry.
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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 6‑105.
How to Check
Use a good quality pocket-type gauge to check
tire pressure. You cannot tell if your tires are
properly inflated simply by looking at them. Radial
tires may look properly inflated even when they
are underinflated. Check the tire's inflation
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 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 you reach the recommended
amount.
If you overfill 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 gauge.
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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High-Speed Operation
{WARNING:
Driving at high speeds, 160 km/h (100 mph) or
higher, puts an additional strain on tires.
Sustained high-speed driving causes excessive
heat build up and can cause sudden tire failure.
You could have 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
are such that a vehicle can be driven at high
speeds, make sure the tires are rated for high
speed operation, in excellent condition, and set to
the correct cold tire inflation pressure for the
vehicle load.
If you will be driving at high speeds, speeds of 100 mph
(160 km/h) or higher, where it is legal, set the cold
inflation pressure to the maximum inflation pressure
shown on the tire sidewall, or 38 psi (265 kPa),
whichever is lower. See the example following. When
you end this high-speed driving, return the tires to the
cold inflation pressure shown on the Tire and Loading
Information label. See Loading the Vehicle
on
page 5‑23. Example:
You will find the maximum load and inflation pressure
molded on the tire's sidewall, in small letters, near the
rim flange. It will read something like this: Maximum
load 690 kg (1521 lbs) 300 kPa (44 psi) Max. Press.
For this example, you would set the inflation pressure
for high‐speed driving at 38 psi (265 kPa).
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
vehicle's 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.
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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
for approximately 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
on page 6‑62for
additional information.
Federal Communications Commission
(FCC) and Industry Canada
See Radio Frequency Statementon page 8‑20for
information regarding Part 15 of the Federal
Communications Commission (FCC) rules and
Industry Canada Standards RSS-210/220/310.
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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, if the vehicle has
one. The TPMS sensors monitor the air pressure in the
vehicle's tires and transmits 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
located on the instrument
panel cluster.
If the warning light comes on, stop as soon as possible
and inflate the tires to the recommended pressure
shown on the tire loading information label. See
Loading the Vehicle on page 5‑23.
At the same time a message to check the pressure in a
specific tire appears on the Driver Information Center
(DIC) display. 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 by the driver. For additional information and
details about the DIC operation and displays see
DIC
Operation and Displays
on page 4‑70and DIC
Warnings and Messages on page 4‑76.
The low tire pressure warning light may come on in cool
weather when the vehicle is first started, and then turn
off as you start to drive. This could be an early indicator
that the air pressure in the tire(s) are getting low and
need to be inflated to the proper pressure.
A Tire and Loading Information label , attached to your
vehicle, shows the size of your vehicle's original
equipment tires and the correct inflation pressure for
your vehicle's tires when they are cold. See Loading the
Vehicle
on page 5‑23for an example of the Tire and
Loading Information label and its location on your
vehicle. Also see Inflation - Tire Pressure
on
page 6‑58.
Your vehicle's TPMS can warn you about a low tire
pressure condition but it does not replace normal tire
maintenance. See Tire Inspection and Rotation
on
page 6‑65and Tires on page 6‑50.
Notice: Using non‐approved tire sealants could
damage the Tire Pressure Monitor System (TPMS)
sensors. TPMS sensor damage caused by using an
incorrect tire sealant is not covered by the vehicle
warranty. Always use the GM approved tire sealant
available through your dealer.
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