Columbus, Ind. (March 29, 2005) - Cummins Inc. (NSYE:CMI) announced today that it had successfully completed a high-mileage durability evaluation of its on-highway ISX engine used in North America. The results, based upon engines with almost 600,000 miles (965,607 km) of commercial service, confirmed company projections that the engines certified and compliant to the 2004 U.S. EPA emissions standards would have the same or better durability than the engines they replaced.

"The proof is in the parts," stated Tom Kieffer, Cummins Executive Director - Marketing. "The analysis concluded that the major contributors to engine durability exhibited outstanding results. In fact, the results indicate that today's ISX engine will have the same or better durability than the N14 engine - long regarded as the industry standard for durability. Our engines are achieving the durability levels we always said they would. With proven durability now added to the ISX performance, reliability and fuel economy leadership as reported by our customers, this means they can depend on our products to provide the best value during their ownership period - and increased resale value.

"For 2007, we will use the same proven cooled-EGR emissions architecture with the addition of the Cummins Particulate Filter. Customers have confidence in our current product durability and tell us that they appreciate the stability our product plans will offer."

Engine durability is typically defined as the point requiring an in-frame engine overhaul resulting from excessive component wear or oil consumption. The evaluation engines were fully disassembled and all major components - from the crankshaft to camshafts, from the EGR subsystem to the power cylinder - were analyzed. Engineering analysis confirmed both the integrity of oil control and combustion control with components exhibiting normal and expected wear. Power cylinder components showed only 20 to 25 percent wear after 600,000 miles (965,607 km), with connecting rod and main bearings expected to have 50 percent additional life remaining.

Cummins Inc., a global power leader, is a corporation of complementary business units that design, manufacture, distribute and service engines and related technologies, including fuel systems, controls, air handling, filtration, emission solutions and electrical power generation systems. Headquartered in Columbus, Indiana (USA), Cummins serves customers in more than 160 countries through its network of 550 company-owned and independent distributor facilities and more than 5,000 dealer locations. With more than 28,000 employees worldwide, Cummins reported sales of $8.4 billion in 2004. Press releases can be found on the Web at www.cummins.com.