Oshkosh Corp. on Tuesday won a $6.75 billion contract to build almost 17,000 new light trucks to replace aging Humvees for the U.S. Army and Marine Corps, cementing the future of its defense business.

The Wisconsin-based company was chosen over competitors Lockheed Martin Corp. and AM General LLC to build as many as 55,000 Joint Light Tactical Vehicles, or JLTVs, over the next 25 years to replace part of the Humvee fleet and some larger military trucks.

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