Mr. Trump has yet to specify changes he might make to Nafta or other industrial policies. But his cabinet appointments, particularly the selection for commerce secretary of the billionaire investor Wilbur L. Ross Jr., who has suggested that he is receptive to some of the antitrade views favored by Mr. Trump, indicate that the incoming president may take an aggressive approach to modifying trade deals and other tenets of the outgoing Obama administration.

One industry analyst, Ron Harbour of the consulting firm Oliver Wyman, said many voters in Rust Belt states like Michigan and Ohio backed Mr. Trump primarily because of his promises to restore manufacturing jobs in the United States.

“So there probably will be pressure to do something,” Mr. Harbour said. “And if he doesn’t do anything, they probably are not going to be too thrilled.”

Mr. Trump will inherit an auto industry that is far healthier than when President Obama took office and industry officials could push back strongly on disruptive changes.

But auto executives generally support Mr. Trump’s choice of a former labor secretary in the George W. Bush administration, Elaine Chao — who is also the wife of the Senate majority leader, Mitch McConnell — to head the Transportation Department. The department oversees fuel-economy and safety rules that affect the types of vehicles that automakers produce.

“We all have a common interest, and that is to maximize the rate of innovation in the technologies that save lives, avoid crashes and improve fuel economy,” the auto alliance said in response to Ms. Chao’s appointment.

No change would be more consequential to the auto industry than applying steep tariffs on imports from Mexico and elsewhere. Companies could be forced to radically change how and where they get commodity parts, the production of which has been migrating to low-wage nations for decades. Consumers could see a change in the types of cars available.