It is not clear what derailed GM and the UAW's progress toward an agreement patterned after earlier deals at Ford and Chrysler-owner Stellantis (STLAM.MI). Pension costs and issues involving the use of temporary workers were among the points of contention at GM, sources said. GM said it was disappointed by the UAW decision to strike Spring Hill. Last month, UAW workers at Mack Truck's U.S. operations overwhelmingly rejected a deal recommended by Fain. In 2015, UAW members at what is now Stellantis voted down a contract endorsed by union leadership.

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Persons: Shawn Fain, Rebecca Cook, Fain, management's, Stellantis, Joe White, David Shepardson, Lisa Shumaker Organizations: United Auto Workers, Ford Michigan Assembly Plant, REUTERS, Rights, Ford, General Motors, Chrysler, GM, UAW, Detroit, Saturday, Union, Mack, Reuters, Thomson Locations: Wayne , Michigan, U.S, Hill , Tennessee, Detroit, Taylor , Michigan, Mack Truck's, Stellantis, Washington