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Detroit Diesel Offers New Lighter Weight Jake Brake

11 February 2000

Detroit Diesel Offers New Lighter Weight Jake Brake(R) Engine Brake for the Series 60(R) Engine

    DETROIT, Feb. 11 -- The next generation Jacobs Engine
Brake(TM) is now available on CY2000 Series 60 engines.  The new engine brake,
Model 790, is the result of an ongoing partnership between Detroit Diesel and
Jacobs Vehicle Systems.  The Model 790 brake offers significant improvements
in performance in a more compact design, weighing 30 pounds less than its
predecessor.  This weight reduction solidifies the Series 60 engine as the
lightest of the full size heavy duty engines, commonly referred to as big bore
engines, available for the North American on-highway market.
    The 30 pound weight reduction was achieved through a simplified design
and the use of higher strength, lighter weight components.  The new brake will
provide improved braking performance and is easier to assemble ensuring higher
quality.
    Braking performance improvements include 5% at rated speed and a full 11%
at mid range rpm where truckers typically operate.  Series 60 engines rated at
330 hp and 350 hp now offer over 400 braking horsepower.  The Model 790 also
uses a standard lash setting for all brake applications, simplifying field
adjustments.
    Detroit Diesel Corporation is engaged in the design, manufacture, sale and
service of heavy-duty diesel and alternative fuel engines, automotive diesel
engines, and engine-related products.  The Company offers a complete line of
diesel engines from 22 to 10,000 horsepower for the on-highway; off-road;
automotive; and power generation markets.  Detroit Diesel services these
markets directly and through a worldwide network of more than 2,800 authorized
distributors and dealer locations.  DDC is a QS-9000 certified company.
    Detroit Diesel's major shareholder is Penske Corporation, a closely-held,
diversified transportation services company whose operations include Penske
Truck Leasing Company, Diesel Technology Company, Penske Automotive Group,
Inc., Penske Auto Centers, Inc., and Penske Capital Partners, L.L.C.  Penske
Corporation and its subsidiaries manage businesses with annual revenues
exceeding $10 billion and employ more than 33,000 people around the world.
    Detroit Diesel's World Wide Web address is http://www.detroitdiesel.com