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Donaldson's Silent Partner Muffler Provides Solution To Engine Brake Noise

20 March 2000

Donaldson Company's Silent Partner(TM) Muffler Provides Solution To Engine Brake Noise - and Wins Technical Achievement Award

    MINNEAPOLIS, March 17 Each year, more heavy-duty vehicles
take to the road equipped with engine brakes -- which give these larger,
heavier, more powerful trucks the greater stopping power they need on
increasingly crowded roads.  According to the U.S. Census Vehicle Inventory
and Use Survey, the total number of vehicles with engine brakes increased 54%
from 1992 to 1997.  Today, almost 90% of all new on-the-highway trucks are
engine brake-equipped.
    But, with growing engine brake use has come a growing number of complaints
about engine brake noise.  The loud, staccato "bark" produced during engine
braking has led to the brakes being banned in communities across America --
and has further hurt the trucking industry's embattled public image.
    However, in 1999, Donaldson introduced the first effective solution to
engine brake noise:  the Silent Partner(TM) muffler.  Silent Partner is the
only muffler designed to minimize the specific noise produced by engine
brakes.
    Unlike previous attempts to solve engine brake noise, the Silent Partner
muffler has no effect on vehicle or engine brake performance, and the unit is
a direct, bolt-on replacement for conventional mufflers.  This makes the
Silent Partner muffler a practical and cost-effective response -- two factors
that are essential to widespread industry acceptance.
    Recently, the Silent Partner muffler was recognized by the Truck Writers
of North America (TWNA) -- who gave Silent Partner their Technical Achievement
Award.  The TWNA Technical Achievement Award is presented for products or
services that have significant potential to improve the trucking industry at
large.  In past years, the award has been given to companies like Caterpillar,
Meritor, Goodyear, Grote Industries, International, Cummins and Eaton.
    Although the patent-pending Silent Partner muffler has many advanced
features, the Award was presented in large part because the Silent Partner
muffler has the ability to provide a broad-based solution to a growing
industry problem.
    In accepting the Technical Achievement Award at the Industry Awards
Luncheon on March 8, 2000, Rod Kunkel, Donaldson's director of global
transportation, described why Donaldson developed the Silent Partner muffler.
"Vehicle noise is just part of the industry's image problem, but it's a very
noticeable part.  Every time a loud truck roars through a town, it hurts
everybody in this business."  He also pointed out that banning engine brakes
was an inherently imperfect solution.  "Bans will prevent truckers from using
one of their most effective safety devices.  And that's bad news for everyone
on the road."
    By introducing the Silent Partner muffler, Donaldson created what Kunkel
called a "win-win" solution for the industry and the public.  "Communities
will get the peace and quiet they've always wanted," he said, "and truckers
will still be able to use their engine brakes whenever it's necessary.
Everybody benefits."