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Donaldson Co. 'Silent Partner' Muffler Wins Nifty Fifty Product Award

18 March 2000

    MINNEAPOLIS - Every year, the technical editors from Heavy Duty Trucking 
Magazine present "Nifty Fifty" Awards to the fifty most significant new 
truck-related products.  In 1999, out of the hundreds of products evaluated, 
the editors chose the Donaldson Silent Partner(TM) muffler for one of these Nifty 
Fifty awards.

    It's easy to see why the editors selected the Silent Partner muffler.  The
Silent Partner is the first muffler developed specifically to address a
growing problem for the trucking industry: complaints about engine brake
noise.

    Engine-braked vehicles have increased in number by over 50% from 1992 to
1997, according to federal vehicle data.  Over 90% of new on-the-highway
vehicles are equipped with engine brakes.  So the loud, harsh, "barking" noise
produced during engine braking has become far more common.  In response,
communities all across the country have banned the use of engine brakes.  And,
every time a loud engine brake annoys the public, it does further harm to the
trucking industry's image.

    Prior to the Silent Partner muffler, there had been other attempts to
solve engine brake noise -- but these solutions were either expensive,
ineffective, or had adverse effects on engine brake operation or vehicle
performance.

    Silent Partner avoids these pitfalls.  While its patent-pending design
reduces engine brake noise to below federally mandated levels, the Silent
Partner muffler has no effect on horsepower, drivability, or engine brake
performance.  In addition, the Silent Partner is a direct bolt-on replacement
for conventional mufflers, so no expensive vehicle modifications are required.

    This makes the Silent Partner muffler the first cost-effective answer to
engine brake noise.  As Rod Kunkel, Donaldson's director of global
transportation, says, "Silent Partner is a win-win solution for everyone.
Communities get the peace and quiet they've always wanted, and truckers will
still be able to use their engine brakes whenever necessary.  Everybody
benefits."

    The Donaldson Silent Partner muffler makes a very real contribution toward
solving a highly visible problem that impacts the whole trucking industry.
And it's a solution that's also drawing attention from the industry press: the
Truck Writers of North America recently presented the Silent Partner muffler
with their Technical Achievement Award.