FLINT, Mich. (WLNS) — General Motors has announced it plans to invest around $1 billion into two Flint facilities.

The Detroit automaker reported a 38% year-over-year increase in heavy-duty pickup sales last year, with nearly 288,000 trucks sold.

The company will invest $788 million in its Flint Assembly.

GM says the Flint Assembly investments will prepare the plan for assembly of the new ICE heavy duty trucks. Plant updates will include a body shop expansion, a general assembly conveyor expansion, as well as new tooling and equipment.

The Flint Assembly is GM’s longest-running assembly plant in North America.

In addition, GM will invest $233 million in its Flint Metal Center.

The Flint Metal Center investment will support production of the ICE heavy duty trucks, and also press refurbishments and new equipment.

Executive vice president Gerald Johnson said the reality of the auto industry now is that companies have to continue to invest in both internal combustion engines and electric vehicles, at least into the next decade. “I can’t tell you what happens beyond that. I don’t think anybody can,” Johnson said. “We can do both.”

But amid the euphoria of getting the $1 billion investment, workers are still a little concerned about what happens after the end of the decade as GM switches to electric passenger vehicles.

“It does raise concerns because we do build big trucks,” said Ryan Buchalski, president of the United Auto Workers local at the plant.

He’s happy that the plant’s future is secure for at least seven to 10 years, and said it will adapt to changes as it always has done. “We were building military vehicles at this plant at one time,” he said.

UAW Vice President Mike Booth, who will lead negotiations with GM in contract talks that are scheduled to begin July 17, said the key to negotiations will be to make sure all workers have jobs in the transition to EVs.

“We’ve very clearly said the conversion from internal combustion engines to electric vehicles, it has to be a just transition,” Booth said. “We’re the ones that built the company, and we want to see ourselves moving it forward into the future.”

This latest investment brings GM’s U.S. manufacturing and parts distribution facility investment commitments to more than $30.5 billion since 2013.