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Detroit Diesel Wins Patent Case

27 May 1999

Detroit Diesel Wins Patent Case

    DETROIT, May 26 -- Detroit Diesel Corporation
(DDC) announced today that the U.S. Court of Appeals for the Federal District
has upheld an earlier ruling in DDC's favor by the U.S. District Court for the
Northern District of Indiana.  Both rulings were in regard to a patent
infringement lawsuit brought against DDC by Caterpillar Inc. .  The
lawsuit, filed in 1995, claimed DDC's Cruise Power feature, an electronic
control option available on DDC's Series 60 engine, infringed a patent held by
Caterpillar.  DDC had denied any infringement and the courts have now decided
the case in DDC's favor.
    John Farmer, Detroit Diesel's Vice President and General Counsel said,
"From the outset, we knew the claim was without merit and, after four years of
extensive litigation, it is gratifying to achieve the appropriate result."
Detroit Diesel's lead counsel in the litigation was Brooks & Kushman P.C. of
Southfield, Michigan.
    The Series 60 engine is the most popular heavy duty, on-highway engine in
North America and DDC will build engine number 500,000 this year.  The next
generation of Detroit Diesel Electronic Controls (DDEC) now under development,
the fifth since DDC pioneered electronic controls on heavy-duty diesel engines
for the trucking industry, will contain a number of innovative features along
with all the other features already available from DDC.
    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
(including power generation), and automotive markets.
    Detroit Diesel services these markets directly and through a worldwide
network of more than 2,800 authorized distributor 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., Penske Motorsports, Inc., and Penske Capital
Partners, L.L.C.  The Penske Group manages businesses with annual revenues
exceeding $10 billion and employs more than 30,000 people around the world.
    Detroit Diesel's World Wide Web address is http://www.detroitdiesel.com.