Noise Control System
Tampering with Noise Control
System Prohibited
The following information relates to compliance with
federal noise emission standards for vehicles with
a Gross Vehicle Weight Rating (GVWR) of more than
10,000 lbs (4 536 kg). The Maintenance Schedule
provides information on maintaining the noise
control system to minimize degradation of the noise
emission control system during the life of your vehicle.
The noise control system warranty is given in your
warranty booklet.
These standards apply only to vehicles sold in the
United States.
Federal law prohibits the following acts or the causing
thereof:
1. The removal or rendering inoperative by any
person, other than for purposes of maintenance,
repair or replacement, of any device or element
of design incorporated into any new vehicle for
the purpose of noise control, prior to its sale
or delivery to the ultimate purchaser or while
it is in use; or
2. The use of the vehicle after such device or element
of design has been removed or rendered inoperative
by any person.Among those acts presumed to constitute tampering are
the acts listed below.
Insulation:
•
Removal of the noise shields or any underhood
insulation.
Engine:
•
Removal or rendering engine speed governor, if the
vehicle has one, inoperative so as to allow engine
speed to exceed manufacturer specifications.
Fan and Drive:
•
Removal of fan clutch, if the vehicle has one, or
rendering clutch inoperative.
•Removal of the fan shroud, if the vehicle has one.
Air Intake:
•
Removal of the air cleaner silencer.
•Modification of the air cleaner.
Exhaust:
•
Removal of the muffler and/or resonator.
•Removal of the exhaust pipes and exhaust pipe
clamps.
Fuel Operated Heater (FOH) — Diesel
Engine:
•
Removal of the muffler.
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(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.
(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
:The service description
indicates the load range and speed rating of a tire.
The load index can range from 1 to 279. The speed
rating is the maximum speed a tire is certified to
carry a load. Speed ratings range from A to Z.
This does not apply to Goodyear LT225/75R16
G949 RSA and Goodyear LT225/75R16 G933 RSD
commercial truck tires; see the dual tire and
single tire maximum load and load range letter
designations on the tire sidewall.
Tire Terminology and De nitions
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.
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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. SeeInflation - Tire Pressure on
page 5-62.
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.
SeeLoading the Vehicle on page 4-18.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. SeeLoading the Vehicle on page 4-18.
GAWR RR
:Gross Axle Weight Rating for the
rear axle. SeeLoading the Vehicle on page 4-18.
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.
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