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International® DuraStar™ With MaxxForce™ Offers Big Improvements In Fuel Economy
New engines help medium-duty customers save at the fuel pump

ATLANTA (February 26, 2008) As diesel fuel prices continue to climb to all-time highs, Navistar has taken the lead in developing fuel-efficient solutions for the medium-duty truck market. International® DuraStar™ 2008 models with new MaxxForce™ engines provide customers with as much as 9 to 13 percent fuel savings over previous models.

“Fuel costs are an increasingly major concern to customers who rely on medium-duty trucks,” said Steve Guillaume, general manager, medium duty, Navistar Truck Group. “We have designed the International DuraStar to work together with our new MaxxForce engines to improve fuel economy and ultimately help customers better manage fuel costs.”

Navistar performed exhaustive testing at a Robert Bosch testing facility in South Bend, Ind., to validate these engines. Several tests were performed that varied body configurations, axle ratios and driving conditions. The results speak for themselves. The MaxxForce 7 demonstrated a fuel efficiency improvement of up to 13 percent versus the previous International VT 365 engine. The MaxxForce DT demonstrated a fuel economy improvement of up to 9 percent versus the previous International DT 466.

“With the combination of DuraStar and MaxxForce, we set out to create a product that was not just reliable, but also fuel efficient,” said Guillaume. “Today, the International DuraStar provides better efficiency at the fuel pump and on the job site.”

In addition to the advances in engine technology that allow the trucks to be more fuel efficient, Navistar recommends tips that can provide customers with better fuel efficiency:

• Synthetic Oils and Lubricants – Low-viscosity synthetic oils and drive train lubricants can be used in front wheel bearings, transmissions and rear axles. Even with the higher cost for synthetics, they can save a truck owner more than $500/year in fuel costs.
• Engine Oil Weight/Grade – Use the engine manufacturer’s recommended engine oil grades. Using a 10W-30 instead of a 5W-30 can decrease miles per gallon by 1-2 percent.
• Tire Pressure – A 15 percent under inflation will average about 1 percent poorer fuel economy. Being under inflated by 30 percent can result in a 3 percent mpg loss.

About Navistar
Navistar International Corporation (Other OTC: NAVZ) is a holding company whose wholly owned subsidiaries produce International® brand commercial and military trucks, MaxxForce™ brand diesel engines, IC brand school and commercial buses, and Workhorse brand chassis for motor homes and step vans. It also is a private-label designer and manufacturer of diesel engines for the pickup truck, van and SUV markets. The company also provides truck and diesel engine parts and service. Another wholly owned subsidiary offers financing services. Additional information is available at  

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