Cummins has submitted its 5.9-liter ISB engine for certification to the Environmental Protection Agency's October 2002 emissions standard.

The company expects to get the certification early this summer, and will begin engine production at that point.
Cummins began sending prototype engines to vehicle manufacturers more than a year ago, enabling them to test their installation processes and prove the engine's capability well ahead of the deadline.
The new ISB was introduced in Europe more than a year ago. To meet the EPA emissions standard, a cooled exhaust gas recirulation (EGR) subsystem was added. The 5.9 liter ISB is designed to meet the needs of medium-duty truck, step van and bus customers. It offers horsepower ratings from 185 to 275 and torque from 420 to 660 pounds-feet. Cummins says the new engine offers as much as 2% improvement in fuel economy with 15,000-mile oil change intervals still standard. Furthermore, the new ISB is up to 80% quieter than its predecessor.
On April 2, Cummins announced that its ISX engine became the first certified engine to the new EPA standard. At that time the company stated that it would certify the ISB engine mid-summer, and the ISM engine prior to the October deadline.