G.M. Workers in Canada Go on Strike

Nearly 4,300 Canadian autoworkers have gone on strike against General Motors, leaving the automaker facing work stoppages in two North American countries.

Workers walked off the job at midnight on Tuesday at three locations in Ontario: a vehicle assembly plant and stamping site in Oshawa that makes the company’s popular Chevrolet Silverado pickup truck; a plant in St. Catharines that supplies engines and transmissions to other G.M. factories around the world; and a parts distribution center in Woodstock.

The strike comes as G.M. and the Canadian union, Unifor, remain deadlocked in negotiation over a new three-year labor contract. Unifor reached agreement with Ford Motor last month and has been pushing G.M. to accept the same terms, a practice known as pattern bargaining that the automakers and their unions have long used.

“This strike is about General Motors stubbornly refusing to meet the pattern agreement,” Unifor’s national president, Lana Payne, said in a statement. “The company knows our members will never let G.M. break our pattern — not today, not ever.”

G.M. Canada said in a statement that it had made a “record offer” to Unifor and “some final items” remain unresolved.

“We are committed to quickly reaching a new collective agreement, so that we can all get back to work while positioning both our people and G.M. Canada for continued success in the future,” the company said.

Ford’s agreement with Unifor provides a 20 percent wage increase for production workers over three years, and a 25 percent increase for skilled trades workers, as well as productivity bonuses, higher entry-level wages, improved pensions, cost-of-living allowances and other improvements.

Workers at G.M.’s CAMI Assembly Plant in Ingersoll, Ontario, are covered by a separate contract and remain on the job. Unifor represents 315,000 workers in a variety of industries.

In the United States, the United Automobile Workers union is on strike at a G.M. pickup truck plant in Missouri, a sport-utility plant in Michigan and parts warehouses around the country. The union is also striking at a Ford plant and a factory and parts warehouses owned by Stellantis, the maker of Chrysler, Jeep and Ram vehicles.

Altogether, about 25,000 of the 150,000 U.A.W. members employed by the three automakers are on strike. Like Unifor, the U.A.W. is seeking a substantial increase in wages, pensions for a greater number of workers, and a shorter time to move up to the top wage level.

Talks began in July, and the strike began on Sept. 15, when the current labor contracts with the companies expired.