Among the possibilities are the Detroit/Hamtramck assembly plant, which makes the Buick LaCrosse, the Chevrolet Impala and Volt, and the Cadillac CT6, all slow-selling cars.
The maneuvers by GM amount to a major restructuring, and it's still too soon to say what kind of long-term impact it will have on the company's stock price.
Trudeau says he is deeply disappointed General Motors is closing its Oshawa assembly plant and will do everything possible to help workers who will lose their jobs.
GM is axing several of its traditional sedan lines to concentrate on electric and autonomous vehicles like the Chevrolet Bolt. "These are things we are doing to strengthen our core business".
GM's stock price surged on the heels of the announcement, closing at 37.65, up almost 5 percent on the day.
Still, GM will shutter three North American auto assembly plants next year: the Oshawa plant in Ontario, Canada; Hamtramck in Detroit, Michigan and Lordstown in Warren, Ohio.
"They said the Chevy Cruze is not selling well", Trump said. They will be part of contract talks with the United Auto Workers union next year. The plan also will end work at plants that make transmissions and other components in Maryland and MI.
"We need to make sure that we are well positioned to compete, not just over the next few years, but well beyond", she said.
Meanwhile, GM's plant in Oshawa, Ontario, will stop making the Impala, Cadillac XTS and 2018 full-size pickups in the fourth quarter of next year.
America's biggest vehicle maker said the move was in response to changing customer tastes, with SUVs and pick-up trucks favoured over sedans that once ruled the country's roads. The expenditures to bring those vehicles to production will start to hit with new batteries and body architectures created to generate profits.
UAW, the autoworkers union, blasted GM's decision, saying the company was just looking for cheaper workers, and vowed to fight back. The Detroit-Hamtramck facility is GM's last in the city, and the Lordstown plant in OH was one of its biggest. The automaker has come under pressure from investors to return more cash in the form of share buybacks and dividends. That includes $4 billion in cost cuts and $1.5 billion in reduced capital expenditures.
GM isn't the first to abandon much of its vehicle market.
GM's actions provoked anger from political figures on both sides of the U.S.
The United Auto Workers, which represents USA workers, vowed to fight the cuts.
General Motors stock jumped to its highest point since July following CEO Mary Barra's announcement of the plan. They are working together to come up with a solution that works for GM and the employees.
The job cuts will include a 25 per cent reduction in executive-level employees to "streamline decision making", the company said.
Even as GM is moving to lay off salaried staff, the company is hiring.
The news out of Detroit Monday offered a stark reminder that the fortunes of Wall Street and Main Street often move in opposite directions. The company said this is part of a plan that restructures to cut costs and focus more on autonomous and electric vehicles.
"We tried to get his attention on this issue two years ago", Mr. Ryan said. "They know they're making a great product. but they also realize that the vehicle is not selling, and, you know, the key is to get another product for this plant".
The president said GM cited poor sales of certain models, rather than a weakening economy.
The plan may signal the demise in the US of several passenger cars that have been struggling, including the Chevrolet Cruze, the Chevrolet Impala and the Cadillac XTS.
A rule of thumb for the automotive industry is that if a plant is running below 80 percent of production capacity, it is losing money.
GM is reportedly slashing 14,700 factory and white collar jobs in North America, and may close five factories. Through the first nine months of 2018, that had fallen to a little over 31 percent. The automaker in June ended the second shift at its factory in Lordstown, Ohio, cutting 1,500 workers.
"I have a family to feed, three kids that I have to support", said George Balsdon, who has worked at the plant for about seven years and said he was "shocked, stressed, didn't really sleep much last night".
At the factories, around 3,300 blue-collar workers could lose jobs in Canada and another 2,600 in the U.S., but some USA workers could transfer to truck or SUV factories that are increasing production.