2011 CADILLAC DTS Owners Manual

Black plate (51,1)Cadillac DTS Owner Manual - 2011
(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 6‑57
and Spare Tireon page 6‑93.
(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.
Light Truck Tire Example
(A) Tire Size:The tire size code 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.
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Black plate (52,1)Cadillac DTS Owner Manual - 2011
(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) Dual Tire Maximum Load
:Maximum load
that can be carried and the maximum pressure
needed to support that load when used in a
dual configuration.
(D) 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.
(E) Tire Identification Number (TIN)
:The letters
and numbers following DOT code are 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.
(F) Tire Ply Material
:The type of cord and
number of plies in the sidewall and under the
tread. (G) Single Tire Maximum Load
:Maximum load
that can be carried and the maximum pressure
needed to support that load when used as a
single. For information on recommended tire
pressure see Inflation - Tire Pressure
on
page 6‑57
.
Tire Size
The following illustration shows an example of a
tire size.
(A) 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.
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Black plate (53,1)Cadillac DTS Owner Manual - 2011
(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 index and speed rating of the
tire. The load index represents the load carry
capacity a tire is certified to carry. The speed
rating is the maximum speed a tire is certified to
carry a load.
Light Truck (LT‐Metric) Tire
(A) Light Truck (LT‐Metric) Tire:The United
States version of a metric tire sizing system. The
letters LT as the first two characters in the tire size
means a light truck 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 75, as
shown in item C of the light truck (LT‐Metric) tire
illustration, it would mean that the tire's sidewall is
75 percent as high as it is wide.
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Black plate (54,1)Cadillac DTS Owner Manual - 2011
(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) Load Range
:Load Range.
(G) Service Description
:The service description
indicates the load index and speed rating of a
tire. If two numbers are given as in the example,
120/116, then this represents the load index for
single versus dual wheel usage (single/dual).
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 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.
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 6‑57
.
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.
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Black plate (55,1)Cadillac DTS Owner Manual - 2011
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 5‑18.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. See Loading the Vehicle
on page 5‑18.
GAWR RR
:Gross Axle Weight Rating for the rear
axle. See Loading the Vehicle
on page 5‑18.
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 5‑18
.
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.
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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 6‑57and Loading
the Vehicle
on page 5‑18.
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 6‑70.
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 5‑18.
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 5‑18.
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Black plate (57,1)Cadillac DTS Owner Manual - 2011
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 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
Loading the Vehicle
on page 5‑18. How you load
your vehicle affects the 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 spare tire. If your vehicle
has a compact spare tire, it should be at 60 psi
(420 kPa). For additional information see Spare
Tire
on page 6‑93.
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Black plate (58,1)Cadillac DTS Owner Manual - 2011
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 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.
Professional Vehicle
The proper inflation of the tires on your
professional vehicle depends on the type of tires
on it.
.If your vehicle has P235/60R17 size tires, the
cold inflation pressure is 41 psi (284 kPa).
.If your vehicle has LT235/60R17E size tires,
the cold inflation pressure depends on the
vehicle mass and should be determined by
the vehicle coach‐builder. A Tire and Loading
Information label provided by the final stage
manufacturer should be attached to the
B‐pillar on the driver's side of the vehicle.
If the final stage manufacturer's label is
not present, the coach‐builder should be
consulted. Do not use the tire pressures
indicated on the General Motors label. These
tire pressures are for the incomplete vehicle
and are not the correct tire pressures for the
completed professional vehicle.
Operation at inflation pressures below this
recommendation may cause your tires to become
overloaded.
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