The Quiet Revolution Begins Today, Reports the Donaldson Company
19 March 1999
The Quiet Revolution Begins Today, Reports the Donaldson Company MINNEAPOLIS, March 16 -- The Donaldson Company
introduced the new Silent Partner Sunday evening, the first practical and
effective solution for engine braking noise. It's an innovation that will
benefit those who own, operate, drive, maintain -- and share the road with --
heavy vehicles, using engine compression brakes.
Over 70 percent of heavy-duty trucks on the road -- and 90 percent of all
new rigs -- use engine brakes. But while more trucks have engine brakes,
engine brake use is being increasingly restricted due to a single factor:
excessive noise.
Engine braking can increase vehicle noise by 100 percent. This noise is
not only louder, but also has a sharp, harsh, unpleasant staccato sound.
Therefore, many municipalities have passed ordinances outlawing engine brake
use, and signs prohibiting engine brakes are becoming common. The noise poses
a problem inside the cab, too. It increases driver discomfort and fatigue,
and on tandem teams, interrupts the off-duty driver's sleep.
Now, however, there is a solution that effectively reduces engine braking
noise: the new Donaldson Silent Partner silencer. Silent Partner's
performance is so superior to conventional mufflers, it is being called the
Quiet Revolution.
Silent Partner is the result of cooperation between two leaders in the
heavy-duty industry. From the beginning of the project, Donaldson worked
closely with Jacobs Vehicle Systems, the company that invented engine brakes
-- and who still supplies over 90 percent of all engine brakes.
Project goals were ambitious. This would be the first silencer to reduce
both acceleration and braking noise inside and outside the cab, while also
eliminating the harsh sound created by engine brakes. In addition, the new
product had to be a bolt-on replacement for existing mufflers. And it needed
to offer high reliability, longer life, and excellent value for the dollar.
All this was to be accomplished without increasing exhaust back pressure or
reducing fuel economy.
To meet these requirements, Donaldson engineers employed the most advanced
technology available. Psycho-acoustic data was gathered using Aachen head
instrumentation, which precisely simulates how humans perceive noise. Using
this information, CAE and supercomputer modeling were used to create and
refine the Silent Partner's design. Then, prototypes were evaluated with
dynamometers, at acoustic labs, and in over a million miles of road and track
testing.
The results were well worth the effort. Donaldson engineers created a
silencer that minimized medium and high frequency noise components -- to
dramatically reduce both drive-by and in-cab noise levels. A Silent
Partner-equipped truck produces half as much engine exhaust noise during
engine braking than a conventionally-muffled truck. Acceleration exhaust
noise was cut by 25 percent. The design also manages to smooth the octave
bands produced by engine braking. This converts the harsh, offensive braking
noise into a warm mellow exhaust tone. Yet, fuel economy and powertrain
performance all remain unaffected.
Silent Partner's innovative design is patent-pending. It is completely
interchangeable with standard mufflers, so no engine or in-cab modifications
are required. Once installed, Silent Partner's aluminized 409 stainless steel
construction helps give it a warranted life of eight years or 1,000,000 miles.
Silent Partner is the only product of its kind approved by Jacobs Vehicle
Systems.
By offering unprecedented performance, Silent Partner provides a wide
range of unique and exclusive benefits:
* Engine brakes can be used more often, improving control and safety;
brake, tire and exhaust life is extended, reducing maintenance and downtime.
* A better in-cab environment improves driver productivity and
satisfaction, which leads to less driver turnover and lower labor costs.
* Fewer noise related complaints (and citations) will help improve the
image of your specific fleet -- as well as the trucking industry in general.
* A quieter truck is seen as a higher quality truck -- which can
translate into higher trade-in or selling prices.
For all these reasons, Silent Partner marks a new era in vehicle noise
control. It truly is the start of a Quiet Revolution.
