Striking Caterpillar workers (left to right) Mark Stanislaus, of Joliet, Bob Casarez, of Shorewood, Bruce Boaz, of Marseilles, and Sean Gallaway, of Braidwood, walk the picket line outside the Caterpillar plant in Joliet, Illinois, Wednesday, June 27, 2012. | Joseph P. Meier~Sun-Times Media

Striking Caterpillar worker Randy Yeates, of Joliet, accompanied by his son Russell, 12, talks about the on going strike after picking up his strike stipend check and some groceries at the headquarters for the International Association of Machinists and Aerospace Workers in Channahon, Illinois, Wednesday, June 27, 2012. | Joseph P. Meier~Sun-Times Media

Striking Caterpillar workers pick up their strike stipend check at the headquarters for the International Association of Machinists and Aerospace Workers in Channahon, Illinois, Wednesday, June 27, 2012. | Joseph P. Meier~Sun-Times Media

Striking Caterpillar worker Tom Platt, of Joliet, walks back to his car after picking up his strike stipend check and some groceries at the headquarters for the International Association of Machinists and Aerospace Workers in Channahon, Illinois, Wednesday, June 27, 2012. | Joseph P. Meier~Sun-Times Media

Striking Caterpillar workers walk the picket line outside the Caterpillar plant in Joliet, Illinois, Wednesday, June 27, 2012. | Joseph P. Meier~Sun-Times Media

Striking Caterpillar workers Mark Stanislaus, of Joliet, (left) and Bob Casarez, of Shorewood, stand at the picket line outside the Caterpillar plant in Joliet, Illinois, Wednesday, June 27, 2012. | Joseph P. Meier~Sun-Times Media

Caterpillar workers in Joliet were on strike from May 1 through Aug. 17 last year. | File Photo

Striking Caterpillar workers Mark Stanislaus, of Joliet, (left) and Bob Casarez, of Shorewood, stand at the picket line outside the Caterpillar plant in Joliet, Illinois, Wednesday, June 27, 2012. | Joseph P. Meier~Sun-Times Media

Striking Caterpillar workers Mark Stanislaus, of Joliet, (left) and Bob Casarez, of Shorewood, stand at the picket line outside the Caterpillar plant in Joliet, Illinois, Wednesday, June 27, 2012. | Joseph P. Meier~Sun-Times Media

Striking Caterpillar workers Bob Casarez, of Shorewood, (left) and Sean Gallaway, of Braidwood stand at the picket line outside the Caterpillar plant in Joliet, Illinois, Wednesday, June 27, 2012. | Joseph P. Meier~Sun-Times Media

Striking Caterpillar workers walk the picket line outside the Caterpillar plant in Joliet, Illinois, Wednesday, June 27, 2012. | Joseph P. Meier~Sun-Times Media