“We are very cognizant that we operate in a cyclical industry, and we are in the eighth year of expansion,” the company’s chief financial officer, Chuck Stevens, said in a conference call last week after the company reported first-quarter earnings. “We are very focused on acting like we are in a downturn.”

The automakers’ comeback since the 2009 crisis had been driven in large part by low gasoline prices that have fed Americans’ tastes for sport utility vehicles and trucks — particularly profitable categories, and the models more likely to be assembled in the United States rather than Mexico. Sales also benefited from pent-up demand as recession turned to recovery.

Now consumers seem to be holding off on spending more broadly — not just on cars, but on other big-ticket items, a primary factor in the economy’s tepid first-quarter performance.

Ford Motor and Fiat Chrysler both saw their sales fall 7 percent or more in April, while Honda’s fell 6.3 percent and General Motors’ 5.8 percent. Toyota declined 3.5 percent, and Nissan dipped 2 percent. (Those figures exclude the Japanese makers’ luxury brands.)

For General Motors, the domestic downturn compounds difficulties it is dealing with abroad. It has announced plans to sell off its Opel and Vauxhall operations in Europe, and on Tuesday it said it would take a $100 million charge to write off the value of its factory in Venezuela, which was seized by authorities in the volatile country two weeks ago.

Like G.M., Fiat Chrysler has idled several thousand workers this year while it retools factories in Toledo, Ohio, and Belvidere, Ill.

Further production cuts may be coming. Many analysts have forecast that auto sales will suffer a small decline this year — to about 17.2 million vehicles from the record of 17.5 million sold in 2016. But some expect the industry to see larger declines after that. AlixPartners, a consulting firm with a large automotive practice, is predicting that auto sales will decline to 16.6 million vehicles in 2018, and 15.2 million in 2019.