General Motors has asked for volunteers among its salaried, non-union employees to cross a picket line and work at its parts distribution centers in the event there is a strike at them, the Detroit Free Press has learned.

That strike came at noon ET on Friday. UAW President Shawn Fain had warned GM, Stellantis and Ford Motor Co. earlier in the week that if substantial progress in contract negotiations was not made, he would expand the strike from the first three plants the union struck one week ago.

Some 5,600 employees at GM and Stellantis parts distribution centers – 38 of them across the country – walked off the job and joined the picket line Friday. Ford Motor Co. was spared the expansion of the strike because Fain said it was making progress in negotiations and had offered up some wins for the union on issues like reinstatement of the cost-of-living adjustment to wages.

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In an internal email obtained by the Detroit Free Press, part of the USA TODAY Network, GM asked team leaders if they had any volunteers to help at the facilities to pack and ship parts in the event of a work stoppage.

The email said GM sought a temporary commitment but noted it would be dependent on the length of the strike. The date of the email is unclear.

When asked about the email, GM spokesman Pat Morrissey did not deny its existence, and another spokesperson provided this statement: "We have contingency plans for various scenarios and are prepared to do what is best for our business and customers. We are evaluating if and when to enact those plans."

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One expert interviewed said asking salaried workers to cross a picket line and do jobs they are not trained to do could be a bad idea.

"That creates all kinds of problems," said Art Wheaton, director of Labor Studies at Cornell University. "The Teamsters have already said, 'We won’t cross the picket lines,' so if any of those parts are being taken out by UPS, they won’t take them. Then you have people who don’t know what they’re doing because it’s not their job to do this kind of work. I don’t see how (GM) could meet their needs by having replacement workers."

But Wheaton said GM will likely do it because, "you plan for contingencies."

One week ago, 13,000 total workers went on strike at three assembly plants: Ford Motor's Michigan Assembly in Wayne, GM's Wentzville Assembly in Missouri and Stellantis Toledo Assembly in Ohio. The union is negotiating for a new contract with all three automakers separately, but simultaneously.

Contact Jamie L. LaReau: [email protected]. Follow her on X @jlareauan.