“The company continues to fall short on our pension demands, income supports for retired workers, and meaningful steps to transition temporary workers into permanent, full-time jobs,” Unifor National President Lana Payne said in a statement.

In a Tuesday bargaining update the company expressed disappointment that it wasn’t able to reach a new agreement with Unifor. “We remain at the bargaining table and are committed to keep working with Unifor to reach an agreement that is fair and flexible for our 4,200 represented employees,” the company said in an unsigned statement.

The Canadian strike comes a day after roughly 4,000 United Auto Workers walked off the job at Mack Trucks factories in Maryland, Pennsylvania and Florida. The UAW also has been running targeted strikes against the Big Three automakers — GM, Ford and Chrysler parent Stellantis — since Sept. 15.

The Unifor strikes include Oshawa Assembly Complex and CCA Stamped Products, St. Catharines Powertrain Plant and Woodstock Parts Distribution Centre, all of which are located in southern Ontario. The plants produce Chevrolet Silverado trucks as well as some V-6 and V-8 engines.

The union said strikes would continue until GM matches the terms of a contract struck with Ford in late September. Unifor said the “pattern agreement” is a baseline for its negotiations with other employers. The Ford deal includes base hourly wage increases of almost 20 percent for production employees and 25 percent for tradespeople, alongside a host of changes to retirement and health-care coverage.

Unifor negotiator Jason Gale said the workers will hold GM to those terms.

“This dispute can only end one way: with GM agreeing to the same terms in our pattern agreement with Ford,” Gale said in a statement.

This is a developing story and will be updated.