COLUMBUS, Ind. (November 2, 2009) -

The Cummins ISB has demonstrated significant fuel economy advantages over competitive engines and is an ideal choice in both the school bus and medium-duty truck markets where maximizing fuel economy is a top priority. The Cummins ISB, which meets the current 2007 EPA emissions standards, won every test segment with results ranging from a 7- to 19-percent lead over MaxxForce engines.

Testing was conducted with an independent third party as well as in-house, using SAE Type III methodology. In total, three different comparisons were completed – each representing real-world scenarios for the school bus and medium-duty truck markets. The tests included vehicles with comparable specifications and load factors. In each assessment, the current Cummins ISB was matched against the MaxxForce 7 and the MaxxForce DT with like horsepower and torque ratings.

“We are delighted at the results of our testing of the ISB against the competition. Fuel economy is incredibly important to our customers, and our testing has validated the clear advantage that customers have with Cummins power,” said Tom Hodek – General Manager, Bus Business for Cummins.

In the school bus market, fuel economy tests were conducted to compare the Cummins ISB with both the MaxxForce 7 and the MaxxForce DT.

? Cummins ISB/MaxxForce DT comparison run on a closed track to constitute a rural school bus route produced a 7.6 percent fuel economy advantage for the ISB-powered school bus.

? Cummins ISB/MaxxForce 7 testing to reproduce an urban school bus route was also administered on a closed track and revealed a 17.2 percent fuel economy advantage for the ISB-powered school bus.

? Cummins ISB/MaxxForce 7 comparison on an interstate route to mirror travel to an activity in an adjacent school district resulted in an 18.8 percent fuel economy advantage for the ISB-powered school bus.

Similarly, fuel economy testing was conducted using medium-duty trucks. This testing and analysis was also completed using SAE Type III methodology with similar vehicle and engine specifications.

? Cummins ISB/MaxxForce DT testing on a closed-track route representative of typical urban pickup and delivery routes measured a 9.6 percent fuel economy advantage for the ISB-powered truck.

? Cummins ISB/MaxxForce DT on an interstate route demonstrated a
 15.4 percent fuel economy advantage for the ISB-powered truck.

The fuel economy leadership proven by the ISB means lower operating costs. For example, in a typical urban school bus route, the 17.2 percent advantage of the Cummins ISB can equal nearly $1,300 in fuel savings per year for each bus. This is assuming 15,000 miles (24,140 km) driven annually and a fuel cost of $3.00 per gallon. Likewise, in a medium-duty truck application with annual mileage of 50,000 miles (80,467 km) and the same $3.00 per gallon of fuel assumption, the 15.4 percent fuel economy advantage of the ISB on an interstate route can save customers over $2,700 in fuel per year for each vehicle.

Through the use of various vehicle, engine and test route evaluations, Cummins has demonstrated that the ISB provides the best fuel economy regardless of vehicle specification or duty cycle for the school bus and medium-duty truck market.

To deliver improved fuel economy while meeting the EPA 2010 near-zero emissions standards, Cummins will use Selective Catalytic Reduction (SCR) technology. Additional Cummins testing shows an estimated 5 to 9 percent fuel economy advantage with SCR technology compared to an in-cylinder-only solution. “For applications including school bus and work truck, the engine is the major influence on fuel economy,” Hodek said. “With our recent testing, we have established our baseline of fuel economy leadership. We fully expect to see increased fuel economy with our 2010 products which will deliver an even greater benefit for our fuel-conscious customers.”

More information on the fuel-efficient ISB is available on

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 approximately 190 countries and territories through a network of more than 500 company-owned and independent distributor locations and approximately 5,200 dealer locations. Cummins reported net income of $755 million on sales of $14.3 billion in 2008. Press releases can be found on the Web at or