All three U.S.-based automakers are doing a better job of satisfying their customers than they were a year ago, according to a recent survey.

General Motors Co., Ford Motor Co. and Chrysler Group LLC all posted significant gains in this year's American Customer Satisfaction Index released Tuesday by the University of Michigan.

"Although the future will obviously be challenging for Detroit, the rise in customer satisfaction provides a much needed improvement in competitive standing," Claes Fornell, the University of Michigan business professor who heads the annual survey, said in a statement.

Fornell said keeping customers happy is key for the automakers, especially at a time when less people are buying cars, because they will be more likely to come back the next time they need a new vehicle.

GM's Cadillac and Toyota's Lexus brands tied for first place in the survey with scores of 89 out of 100. That marked a 4 point increase for Cadillac from its 2008 results and a 2 point improvement for Lexus, which also ranked first in last year's survey.

GM's Buick brand, Honda and Ford's Lincoln Mercury vehicles all received an 88. The Lincoln Mercury score marked a 5 point increase over its results for the previous year, while Buick's score rose by 3 points.

BMW received an 87, while Mercedes, Toyota and Volkswagen each got an 86. Volkswagen's increase of 5 points, or 6.2 percent, marked the biggest jump from the year before.

Hyundai received an 85, while the Chrysler's namesake brand rose 4 points to 84. GM's Saturn brand also got an 84.

The Chevrolet and Ford brands rose by 4 points and 3 points respectively to 83, while GMC fell by 1 point to 82.

Dodge, Kia, Mazda and Pontiac all received an 81. Jeep and Nissan, fell to the bottom of the pack with a 79 and 78, respectively. Nissan was one of the few brands to post a decrease from the year before, falling 4 points, or 4.9 percent.

The overall automotive industry's score was 84, up from 82 the year before.

There were over 11,000 telephone surveys conducted and about 5,500 for the auto industry in the second quarter of this year, asking respondents to rate their satisfaction of the vehicles on a scale of zero to 100. At the industry level, the margin of error is plus or minus 1 point. At the company level it is plus or minus 3 points.