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Detroit Diesel Introduces Optimized Idle For Bus & Coach Market

4 May 1999

Detroit Diesel Introduces Optimized Idle For Bus & Coach Market

    DETROIT, May 4 -- Detroit Diesel Corporation
(DDC) announced the introduction of Optimized Idle(TM) for the Bus and Coach
market.  Optimized Idle, a feature of the Detroit Diesel DDEC III and IV
Electronic Control Module, limits engine idle time to only those times that
require it, based on engine temperature, battery voltage or interior
temperature.
    During periods when the vehicle is not moving the Optimized Idle system
automatically starts and stops the engine as necessary to maintain the engine
temperature and battery voltage within pre-set limits.  With the optional
thermostat, Optimized Idle will monitor the interior temperature of the bus or
coach.  When the temperature rises above or drops below a customer set comfort
level, Optimized Idle will start the engine to heat or cool the interior back
to its comfort zone, very much like the thermostat in a typical home.
    Unnecessary engine idling increases stronger operating costs by lowering
overall fuel economy, shortening maintenance intervals and reducing engine
life through increased wear.  Optimized Idle provides significant cost savings
and environmental benefits through idle reduction which saves fuel while
requiring no additional maintenance.
    "Detroit Diesel's DDEC Optimized Idle is based on patented, field proven
start/stop technology," said Patrick Scully, Vice President of Bus & Coach
Sales.  "We have seen positive results from the truck industry and we are
excited to be introducing it to the Bus & Coach market."
    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 of businesses has annual revenues exceeding
$6 billion and employs more than 28,000 people around the world.