The United Auto Workers strike expanded Wednesday to a drivetrain plant in Tuscaloosa, Ala., ZF Chassis Systems, a supplier of axles to a nearby Mercedes factory, The Hill reports.

It is the fourth auto manufacturing plant to join the UAW strike, which began Friday at a General Motors plant in St. Louis, a Ford plant in Wayne, Mich., and a Stellantis facility in Toledo, Ohio.

Union members are seeking higher wages, four-day work weeks, union representation for battery plant workers, and the restoration of pension benefits, including for new hires.

UAW Shawn Fain has threatened that the strikes will extend to more plants if automakers don’t improve their contract offers by noon Friday.

“Our members have been clear about their demands, and we know the companies can afford to make things right,” Fain said Wednesday. “Record profits mean record contracts. We’ve been available 24/7 to bargain a deal that recognizes our members’ sacrifices and contributions to these record profits.”

Fain added: “If we don’t make serious progress by noon, on Friday, September 22, more locals will be called on to stand up and join the strike.”

By having only a few local facilities strike, the UAW’s strategy, Fain said, is to “keep the companies guessing.”

President Joe Biden has spoken in support of the union strike, saying of the Big 3 automakers, “I believe they should go further. … Record corporate profits, which they have, should be shared by record contracts for the UAW.”

Former President Trump said Tuesday he will visit the striking workers in Detroit instead of attending the second GOP presidential primary debate taking place Sept. 27 at the Ronald Reagan Presidential Library, in Simi Valley, Calif