Hercules expanded greatly in the interwar period, developing gas and diesel engines, serving the needs for truck, tractor and a plethora of equipment operators.

During World War II the company produced about 750,000 gasoline and diesel engines for Allied military vehicles, ships, and various equipment.

[3] But Hercules could not respond effectively to changes in the post-WWII engine market, so WWII remained its high water mark in terms of output, earnings and profits.

White Truck was a huge and growing firm at the time (about $1 billion in sales) and it laid out ambitious plans for Hercules expansion, beginning product development and construction of a new plant in Canton.

White sold Hercules to Wedtech in 1986, which held the engine maker only briefly, before selling to a group of investors the next year.