DETROIT — Gamil Aljohaim knows the workers at the Detroit-Hamtramck Assembly plant by the vehicles they drive.

In the days after General Motors announced what has been interpreted as a looming shutdown at the plant and four others in North America, Aljohaim said he saw fewer of those trucks at his I-94 Gas and Go, and some of those who did come were choosing to put less gas in the tank.

“After they heard this news, they started holding on to their money,” Aljohaim said. “I feel bad for them.”

Aljohaim, whose service station sits across a highway overpass from the sprawling plant, is concerned about his own shop, which he said gets as much as 40 percent of its business from the more than 1,540 workers at the factory.

While it’s not clear in the short term whether the people who drive to and from work at the plant would be able to continue limiting their fuel purchases, the almost immediate reaction Aljohaim noticed demonstrates that even the threat of potential auto job losses can ripple across the economy.

GM said it plans to cut 14,000 jobs as part of a restructuring, affecting plants in Michigan, Ohio, Maryland and Ontario, along with 8,000 white-collar workers.

The Detroit automaker, however, said it is still hiring for areas focused on electrification and autonomous vehicle development.

While some experts say the specific impact in the Detroit area of these particular potential job losses could be limited in scope, the drop in business at a local service station shows how auto jobs in particular affect many other industries.

That’s especially true in a state like Michigan, where auto industry employment is such a major part of the labor force (11.2 percent, according to the Center for Automotive Research in Ann Arbor).

More than 7 million private sector jobs are supported by automakers, suppliers and dealers in the United States, and the industry is responsible for $500 billion in annual compensation to the workers it supports, according to CAR, which attributed more than 570,000 jobs just in Michigan, including spin-off, to automakers in 2014.

“It’s estimated by various authorities that for every job there is in the automotive industry there are ripple effects that impact seven to nine jobs . so if you have an industry that is employing 1,500, you can multiply that by 7 to 9” to see what could come from a loss of the Detroit-Hamtramck plant, said Marick Masters, a professor of business at Wayne State University.

Masters said the potential direct loss of 1,500 jobs represents a fraction of overall economic activity in the state, but it is significant for a variety of reasons.

“When you’re talking about perhaps 10,000 people being adversely affected, that’s a significant number, and there are human stories behind each of those numbers,” Masters said.

“(An) automotive assembly job has one of the highest multipliers of any job in the industry,” affecting everything from steel to logistics to cafeteria work, said Kristin Dziczek, vice president of Industry, Labor and Economics at CAR. “Anything that GM buys is tied to that employment as well . and these jobs pay better than a lot of other jobs in the economy.”

The money that workers earn also supports lots of other businesses not directly tied to the auto industry, those that provide everything from groceries to child care to boats.

Autoworkers are not the only people who buy boats, but they certainly contribute to Michigan’s high ranking for boat registrations.

The state was third nationally behind Florida and Minnesota in 2017, up 0.6 percent from the prior year to 798,544, according to the National Marine Manufacturers Association.

The association notes that “Michigan’s recreational boating industry has an annual economic impact of more than $7.4 billion.” If fewer boats are purchased, that number would also take a hit.

Down the street from Aljohaim’s service station on Thursday, Joseph Gojanaj stopped to chat during a break from frying omelets and hash browns at the Legends Grill he owns.

“Our lunches will probably be a lot slower,” Gojanaj said of the impact from a potential shutdown at the Detroit-Hamtramck plant.

Gojanaj predicted that the restaurant would be able to survive, but he said a shutdown would still have a big effect on his business.

Glenn Stevens, executive director of MICHAuto and vice president of automotive and mobility initiatives for the Detroit Regional Chamber, said nobody wants to hear about job losses, and noted there are other opportunities in the industry because there’s a “tremendous need across the (automakers) and supply chain for talent.”

He said GM, along with the rest of the industry, has been reactive in the past.

“I really see this as a move to make sure this company is here for a long time, (which) is very important for this area,” Stevens said.