OSHKOSH, Wis. (WTAQ) - Union workers at Oshkosh Corporation have turned down the company's latest contract extension.

Oshkosh's offer included a 3.5 percent raise, $750 signing bonus and no increases in health or dental premiums.

United Auto Workers Local 578 President Perry Graves says the members' vote Sunday had more to do with concerns about how employees are treated, rather than the economics of the deal. Graves more specifically says those concerns include family and medical leave, how grievances are handled and other workplace issues.

The Local 578 has 2,750 members, according to the Oshkosh Northwestern.