NEW YORK — U.S. car buyers are growing less satisfied with their purchases from domestic automakers while their Asian and European competitors continue to improve, according to a recent survey.

Consumer satisfaction with U.S. auto brands slipped as Lexus and BMW tied for first place, followed by Toyota and Honda, according to the University of Michigan's American Customer Satisfaction Index released today.

General Motors Corp.'s Buick and Cadillac brands, and Ford Motor Co.'s Lincoln and Mercury lines, fell from their No. 2 perch at a time when U.S. companies are struggling to outshine their competitors and reverse their shrinking sales and market share.

That's an unsettling sign for domestic automakers, said Claes Fornell, the University of Michigan business professor who heads the annual survey. Traditionally, U.S. brands improve their customer satisfaction scores each year, just not as much as their overseas counterparts. Now, the domestic companies' ratings are declining while their competitors' scores continue to climb.

Just 11 points separate the best-scoring brand from the worst, but domestic automakers are having the hardest time adapting to high gas prices and a shift in demand toward more fuel efficient vehicles, and that is manifesting itself in weaker customer satisfaction, Fornell said.

"I think there is little question that the domestic automakers are somewhat strapped for resources, and they have to go out and borrow money and stuff like that," he said. "Whenever they have to do that, it is difficult to come up with the same level of quality and the same level of customer satisfaction."