Negotiations impact about 43-hundred unionized workers in St. Catharines, Oshawa and Woodstock.
Canada's largest private sector union will open talks today with General Motors.
This comes after Unifor members voted to accept the union's new three-year labour agreement with Ford.
But the 54%t favourable vote was in stark contrast to support for the previous contract, which was 81%.
Experts are speculating that reaching deals with G-M and Stellantis could prove more challenging, especially since those companies are bigger and more profitable.
Unifor's negotiations with G-M cover about 43-hundred unionized workers at three sites in St. Catharines, Oshawa and Woodstock.

Man dies in single vehicle crash on Merrittville Highway
Assault Not Motivated by Hate: NRP
MRI Machines in Niagara Not Fully Used
Pedestrian Killed in Niagara Falls
Thorold Man Arrested for Drug Trafficking
Police Looking for Missing Man
Budget Tops Chiocchio's Long List of Priorities
Child Cancer Clinic Coming to Niagara