Even as sales remain in a slump, American car buyers’ sentiment toward their new vehicles climbed to an all-time high in second-quarter 2009, compared with year-ago, a recent study reveals, with Ford Motor Co. and Volkswagen of America Inc. as the primary beneficiaries.

The University of Michigan’s American Customer Satisfaction Index, an annual second-quarter measurement of durable goods and e-business, shows consumers’ approval of their new vehicles rose a combined 2% to 84 points on a 100-point scale, marking a record high.

Combining the performance of Ford (up 3.8%) and Lincoln Mercury (up 6%) brands, Ford tracked 5% ahead of year-ago, the ACSI finds.

Volkswagen reaped the largest satisfaction gain by any company, automotive or otherwise, up 6.2% and besting the industry average for the first time in five years.

Chrysler Group LLC posted a combined 4% gain, while General Motors Co. climbed 2% on the index.

The ACSI results note if the discontinued Saturn and Pontiac brands, with scores of 84 and 81, respectively, were excluded from GM’s score, GM would have tied with Ford.

“Although the future will obviously be challenging for Detroit (auto makers), the rise in customer satisfaction provides a much-needed improvement in competitive standing,” says Claes Fornell, a U. of M. professor who heads the ACSI study.

“Making sure that customers are satisfied will be a most important task for the auto makers, because it leads to higher levels of repeat purchase and fewer customer defections. If they were to remain at the bottom of customer satisfaction in their industry, these companies would not be able to survive.”

GM’s Buick and Cadillac, Ford’s Lincoln Mercury and Chrysler’s Jeep and Chrysler brands all were among the most-improved in the ACSI, despite a 50% drop or more in sales over the past year.

Indeed, for the first time in a decade, domestic auto makers ranked on a par with Asian brands, the ACSI shows.

While consumer recognition of quality improvements is behind some of the higher ratings, the second-quarter survey also reflects fewer car buyers.

Fornell says “a smaller, more-satisfied customer base” for domestic brands is not a bad thing. It will be “less difficult to grow” and easier to “defend against competitive inroads” than a larger, diversified consumer group.

Among brands, Cadillac and Toyota Motor Sales U.S.A. Inc.’s Lexus ranked highest in the standings, with 89 points each. Buick, Lincoln Mercury and Honda each garnered 88.

BMW of North America LLC’s BMW brand earned a customer satisfaction rating of 87, followed by Daimler AG’s Mercedes-Benz USA, Toyota and Volkswagen brands, all achieving 86 points.

The Chrysler brand scored an industry average of 84 points, up 5% from year-ago, while Dodge (up 3.9%) and Jeep (up 3.8%) earned 81 and 79, respectively.

The ACSI results for Asian brands show a mostly flat performance in the quarter, with Honda seeing a 2% gain to 88 points, Hyundai receiving 85 points, up 2.4%, and Kia and Mazda earning 81 points, both up 1%.

The Nissan brand was the worst automotive performer in the second-quarter 2009 survey, compared with like-2008, down 5% to 78 points, which ACSI blames on “recent quality problems.”

This year’s overall ACSI score, which also measures customer sentiment about personal computers, major appliances, Internet portals and search engines, as well as news and information websites, was 76.1, climbing 0.1% from year-ago.

The automobile sector’s 2.4% rise was second only to the gain seen by portals and search engines, up 3.8%, ACSI says.