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Black plate (55,1)Cadillac SRX Owner Manual - 2011
Vehicle Care 10-55
WARNING (Continued)
.Replace any tires that have
been damaged by impacts
with potholes, curbs, etc.
.Improperly repaired tires can
cause a crash. Only your
dealer or an authorized tire
service center should repair,
replace, dismount, and mount
the tires.
.Do not spin the tires in
excess of 55 km/h (35 mph)
on slippery surfaces such
as snow, mud, ice, etc.
Excessive spinning may
cause the tires to explode.
See Tire Pressure for High-Speed
Operation on page 10‑62 for
inflation pressure adjustment
for high-speed driving.
Tire Sidewall Labeling
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.
Passenger (P‐Metric) Tire Example
(A) Tire Size:The tire size is
a combination of letters and
numbers used to define 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.
(B) 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.
(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.
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Black plate (56,1)Cadillac SRX Owner Manual - 2011
10-56 Vehicle Care
(D) 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.
(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 10‑73. (G) Maximum Cold Inflation
Load Limit
:Maximum load
that can be carried and the
maximum pressure needed
to support that load.
Compact Spare Tire Example
(A) Tire Ply Material:The type
of cord and number of plies in
the sidewall and under the tread.
(B) Temporary Use Only
:
The compact spare tire or
temporary use tire has a tread
life of approximately 5 000 km (3,000 miles) and should not be
driven at speeds over 105 km/h
(65 mph). The compact spare
tire is for emergency use when
a regular road tire has lost air
and gone flat. If your vehicle
has a compact spare tire,
see
Compact Spare Tire on
page 10‑93 andIf a Tire Goes
Flat on page 10‑77.
(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.
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Black plate (57,1)Cadillac SRX Owner Manual - 2011
Vehicle Care 10-57
(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 420 kPa (60 psi). For more
information on tire pressure and
inflation see Tire Pressure on
page 10‑61.
(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 Designations
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.
(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.
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Black plate (58,1)Cadillac SRX Owner Manual - 2011
10-58 Vehicle Care
(E) Rim Diameter:Diameter of
the wheel in inches.
(F) 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 psi (pounds per
square inch) or kPa (kilopascal).
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.
Cold Tire Pressure
:The
amount of air pressure in a tire,
measured in kPa (kilopascal)
or psi (pounds per square inch) before a tire has built up heat
from driving. See
Tire Pressure
on page 10‑61.
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 Vehicle Load Limits
on page 9‑12.
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Black plate (59,1)Cadillac SRX Owner Manual - 2011
Vehicle Care 10-59
GAWR FRT:Gross Axle
Weight Rating for the front axle.
See Vehicle Load Limits on
page 9‑12.
GAWR RR
:Gross Axle
Weight Rating for the rear axle.
See Vehicle Load Limits on
page 9‑12.
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 68 kg (150 lbs).
See Vehicle Load Limits on
page 9‑12.
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 Tire Pressure on
page 10‑61 andVehicle
Load Limits on page 9‑12.
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Black plate (60,1)Cadillac SRX Owner Manual - 2011
10-60 Vehicle Care
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 1.6 mm
(1/16 inch) of tread remains.
See When It Is Time for New
Tires on page 10‑69.
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 10‑73. Vehicle Capacity Weight
:
The number of designated
seating positions multiplied by
68 kg (150 lbs) plus the rated
cargo load. See
Vehicle Load
Limits on page 9‑12.
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” underVehicle
Load Limits on page 9‑12.
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Black plate (61,1)Cadillac SRX Owner Manual - 2011
Vehicle Care 10-61
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 shows your vehicle's
original equipment tires and 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
Vehicle
Load Limits on page 9‑12.
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 the vehicle has one.
The compact spare should
be at 420 kPa (60 psi).
For additional information
regarding the compact spare
tire, see Compact Spare
Tire on page 10‑93.
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Black plate (62,1)Cadillac SRX Owner Manual - 2011
10-62 Vehicle Care
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 under‐inflated. 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 1.6 km (1 mile).
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.Tire Pressure for
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.