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Black plate (6,1)Cadillac DTS Owner Manual - 2011
Otherwise, you could damage the engine. If heavy
knocking is heard when using gasoline rated
at 87 octane or higher, the engine needs service.
Gasoline Specifications
At a minimum, gasoline should meet ASTM
specification D 4814 in the United States or
CAN/CGSB‐3.5 or 3.511 in Canada. Some
gasolines contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT). We recommend against the use of gasolines
containing MMT. SeeAdditives
on page 6‑6for
additional information.
California Fuel
If the vehicle is certified to meet California Emissions
Standards, it is designed to operate on fuels that meet
California specifications. See the underhood emission
control label. If this fuel is not available in states
adopting California emissions standards, the vehicle
will operate satisfactorily on fuels meeting federal
specifications, but emission control system performance
might be affected. The malfunction indicator lamp could
turn on and the vehicle might fail a smog‐check test. See
Malfunction Indicator Lamp
on page 4‑54. If this
occurs, return to your authorized dealer for diagnosis.
If it is determined that the condition is caused by the
type of fuel used, repairs might not be covered by the
vehicle warranty.
Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that help prevent
engine and fuel system deposits from forming, allowing
the emission control system to work properly. In most
cases, nothing should have to be added to the fuel.
However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. To help keep fuel
injectors and intake valves clean, or if the vehicle
experiences problems due to dirty injectors or valves,
look for gasoline that is advertised as TOP TIER
Detergent Gasoline.
For customers who do not use TOP TIER Detergent
Gasoline regularly, one bottle of GM Fuel System
Treatment PLUS, added to the fuel tank at every engine
oil change, can help clean deposits from fuel injectors
and intake valves. GM Fuel System Treatment PLUS is
the only gasoline additive recommended by General
Motors.
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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 (94,1)Cadillac DTS Owner Manual - 2011
Spare Tire
This vehicle may have a spare tire, which, when new,
was fully inflated. A spare tire may lose air over time, so
check its inflation pressure regularly. SeeInflation - Tire
Pressure
on page 6‑57and Loading the Vehicleon
page 5‑18for information regarding proper tire inflation
and loading your vehicle. For instructions on how to
remove, install or store a spare tire, see Removing the
Flat Tire and Installing the Spare Tire on page 6‑86.
After installing the spare tire on your vehicle, you should
stop as soon as possible and make sure the spare is
correctly inflated. Have the damaged or flat road tire
repaired or replaced as soon as you can and installed
back onto your vehicle. This way, a spare tire will be
available in case you need it again.
Your vehicle may have a different size spare tire than
the road tire originally installed on your vehicle. This
spare tire was developed for use on your vehicle, so it
is all right to drive on it.
If your vehicle has a spare tire that does not match your
vehicle's original road tires and wheels in size and type,
do not include the spare in the tire rotation.
Appearance Care
Interior Cleaning
The vehicle's interior will continue to look its best if it is
cleaned often. Although not always visible, dust and dirt
can accumulate on the upholstery. Dirt can damage
carpet, fabric, leather, and plastic surfaces. Regular
vacuuming is recommended to remove particles from
the upholstery. It is important to keep the upholstery
from becoming and remaining heavily soiled. Soils
should be removed as quickly as possible. The
vehicle's interior may experience extremes of heat
that could cause stains to set rapidly.
Lighter colored interiors may require more frequent
cleaning. Use care because newspapers and garments
that transfer color to home furnishings may also transfer
color to the vehicle's interior.
When cleaning the vehicle's interior, only use cleaners
specifically designed for the surfaces being cleaned.
Permanent damage may result from using cleaners
on surfaces for which they were not intended. Use
glass cleaner only on glass. Remove any accidental
over-spray from other surfaces immediately. To prevent
over-spray, apply cleaner directly to the cleaning cloth.
6-94