CHICAGO (March 4, 2009) – Continuing on its commitment to clean technologies that benefit the environment and its customers, Navistar (NYSE: NAV) today unveiled its newest hybrid truck, the International® WorkStar® Hybrid 4x4—the industry’s first four-wheel drive diesel-electric hybrid commercial truck.

The International WorkStar Hybrid 4x4, part of the International severe service line-up of trucks for heavier duty applications, adds to Navistar’s industry-leading line-up of diesel-electric hybrid vehicles. Navistar also produces the medium-duty International® DuraStar® Hybrid as well as IC Bus brand diesel-electric hybrid passenger buses for both school bus and commercial bus applications.

“With the new International WorkStar Hybrid 4x4 in our lineup, we continue to lead the way in providing energy-saving, environmentally friendly solutions for our customers,” said Steve Guillaume, Navistar general manager, vocational trucks. “By developing another hybrid truck that reduces fuel consumption and greenhouse gas emissions, we’re able to deliver significant savings to the customers’ bottom line and, at the same time, help them reduce their overall carbon footprint.”

The International WorkStar Hybrid 4x4 can provide dramatic fuel savings of nearly 60 percent in utility-type applications when the engine often can be shut off, but electric power still operates the vehicle. Beyond the fuel savings potential, the WorkStar Hybrid 4x4 produces zero emissions when auxiliary equipment (like an overhead utility bucket) operates solely on the truck’s hybrid battery power. The four-wheel drive capability of the truck is ideal for customers like utility companies, who need a truck to operate in off-highway conditions but are also looking to save energy and project a green image.

The Hybrid Truck Users Forum (HTUF), a national group of utility companies that own hybrid trucks, estimates that 1,000-1,500 gallons of fuel can be saved per utility truck annually. At the high diesel prices seen throughout most of 2008, that equates to a savings of $4,000-$6,000 in fuel per truck annually. It also results in annual greenhouse gas reductions of 11 to 16.5 tons of carbon dioxide per unit.

The International line-up of hybrid commercial trucks uses a mild parallel-type, diesel-electric hybrid architecture, developed by Eaton Corporation, which leads to less diesel fuel use and fewer emissions. The hybrid-electric system utilizes a regenerative braking system to recover energy normally lost during braking, stores the energy in batteries and adds power back into the driveline during starts and acceleration.

This capability makes the truck more efficient in standard driving, particularly in city and stop-and-go driving. When the truck reaches a work site, the hybrid system can power booms, aerial devices and other tools needed at the location for up to 90 minutes without the engine running, significantly reducing noise, emissions and fuel costs.

For decades, Navistar has demonstrated its commitment to clean technologies that benefit the environment and its customers. Navistar was the first Original Equipment Manufacturer (OEM) to release the smokeless diesel engine and was the first engine manufacturer to gain EPA certification for meeting 2007 particulate and hydrocarbon emissions standards – six years ahead of schedule. Navistar was also the first OEM to enter line production of diesel-hybrid commercial trucks and school buses in North America.

For its ongoing leadership, Navistar was honored with the 2007 Blue Sky Award from WestStart-CALSTART for its contributions to the commercial development of diesel-hybrid technology. This preeminent award is presented each year by WestStart-CALSTART, the nation's leading advanced transportation technology industry organization working to support and accelerate the growth of companies developing clean and energy-efficient transportation technologies.

Most recently, Navistar became the first OEM to receive dual certification through the U.S. Environmental Protection Agency (EPA) SmartWay Program for helping to reduce greenhouse gas (GHG) emissions. Navistar produces two industry-leading Class 8 trucks with SmartWay certification, International® LoneStar® and International® ProStar®, a distinction they received for their superior aerodynamics and fuel economy. While the ProStar is the most fuel-efficient Class 8 tractor on the market, in June 2009, the groundbreaking LoneStar became the first classic-styled Class 8 tractor to receive the SmartWay certification. In January 2009, Navistar also became a SmartWay Transport Partner, becoming the first OEM with SmartWay-certified tractors to also be certified as a transport partner. The SmartWay Transport Partnership is a voluntary program that recognizes partners for setting and achieving greenhouse gas (GHG) reduction goals in freight transport. The program also helps lower operating costs by reducing fuel surcharges and offers customers EPA-certified, fuel-efficient tractors.