“We will shut down part distribution until those two companies come to their senses and come to the table with a serious offer,” Fain said. “Stellantis and GM in particular are gonna need some serious pushing.”

The UAW is going after GM and Stellantis’ custom service operators as a way to prod them for more concessions without going after plants producing the highest-profit margin vehicles. A dearth of parts means vehicle owners will wait longer to get their cars fixed and dealers lose out on service revenue.

Stellantis and GM didn’t immediately respond to a request for comment.

Ford shares rose as much as 4.6% on Friday. GM and Stellantis climbed less than 1% as of 10:54 a.m. in New York. Ford and GM have underperformed the S&P 500 Index’s 13% gain this year while American depositary receipts for Stellantis have risen 38%.

Week-Old Strike

The union ordered a work stoppage starting a week ago at a GM factory in Missouri that assembles Chevrolet Colorado pickups, a Stellantis facility in Ohio that builds Jeep Wrangler SUVs and a Ford plant in Michigan that makes Bronco SUVs.

Fain said the strike targeting the Ford factory in Michigan will not be expanded at the current time, adding talks with the automaker have seen “some real progress.” He applauded the automaker for officially reinstating a cost of living allowance suspended in 2009.

Ford welcomed the olive branch from the union’s leadership, but noted more needs to be resolved before a deal is in hand.

“Although we are making progress in some areas, we still have significant gaps to close on the key economic issues,” the company said in a statement after Fain’s address. “The issues are interconnected and must work within an overall agreement that supports our mutual success.”

For GM and Stellantis, the news was less encouraging. The 38 parts facilities represents all of those two companies’ parts distribution hubs in the US.

“The parts plant strike could force dealers to run out of parts immediately since supply chain issues have already put many components on back order,” said Sam Fiorani, vice president of forecasting for AutoForecast Solutions.

The additional GM and Stellantis facilities will be subject to a walkout as of 12 p.m. local time Friday, Fain said.