Customer satisfaction with car companies dropped slightly from last year, according to the American Customer Satisfaction Index (ASCI).
The index tracks how happy people are with the things they buy.
Satisfaction dropped even more for Detroit automakers.
Claus Fornell is the founder of the index. He says two years ago, satisfaction with Detroit car companies and Japanese competitors was a tie. Now, there's a gap again - and it's the widest in five years.
"It is a situation that should be seen as a warning signal, I think," he says.
Fornell says U.S. car factories are operating at or above capacity right now and that could explain why more quality problems are showing up, reducing satisfaction with car purchases.
Car salespeople may also have less time to attend to customers' needs, because they're moving the metal so fast.
Customer satisfaction is considered a leading indicator, meaning an uptick in satisfaction should presage an uptick in the economy.
Fornell says customer satisfaction with all goods is essentially flat.