Waukesha, Wisconsin-based company, Odyne Systems LLC, makes hybrids of medium / large trucks.
From the 'about us' page:
Odyne, a clean technology company, develops and manufactures plug-in hybrid electric drive systems for medium and heavy duty trucks. Odyne's hybrid technology enables vehicles to have substantially lower fuel consumption, lower emissions, improved performance, quiet jobsite operation and reduced operating and maintenance costs. Our mission is to design and commercialize Plug-In Hybrid Electric Vehicle (PHEV) propulsion systems for medium and heavy duty trucks by harnessing the strengths of environmentally friendly and cost effective technologies.
Regards,
Keith