US car buyers' satisfaction has rebounded as domestic and mass-market brands improve, according to the American Customer Satisfaction Index (ACSI).

Customer satisfaction with automobiles was up 3.8% to 82 on ACSI's 100-point scale. Luxury cars have dominated driver satisfaction rankings for years but the top tier is now evenly split between mass market and luxury vehicles.

"The rise of mass-market vehicles may well be at the expense of luxury brands in the sense that buyers now see little differentiation between luxury cars and regular ones," said Claes Fornell, ACSI chairman and founder. "If there is little difference, why pay more? Exclusivity may not be enough."

Among 24 vehicle brands tracked by ACSI, 16 improved while five declined - three of which were premium brands. The most notable decline was for Volkswagen, which is embroiled in an emissions-cheating scandal that has angered customers, government officials, and consumer and environmental advocates. In a year dominated by improving customer satisfaction, Volkswagen dropped 3% to 78, tied for lowest among mass-market vehicles.

"The combination of fines and fallen stock price are a big hit to Volkswagen's finances, but it may prove even harder to recover from the reputational hit the company will take for deceiving customers and the general public," said David VanAmburg, ACSI director. "Many customers or would-be customers could be turned-off of VW for life and it's hard to put a value on that."

All domestic automakers improved customer satisfaction overall this year and the highest-scoring car was an American brand. Ford's Lincoln took the lead with a 5% jump to an ACSI score of 87. Honda claimed second place with an 8% gain to 86 while Toyota and BMW each advanced 4%, placing these luxury and mass-market brands in a tie for third place at 85.

Lexus, which previously held first place, is now matched by GMC (+8%), Subaru (+2%) and Nissan's Infiniti - the leading gainer with a 9% jump to 84. Audi (+6%) and Chevrolet (+5%) followed close with 83. The rest of the industry came in below the industry average. The Ford brand edged up 3% to 81, catching up with Mercedes-Benz (-2%) and Hyundai (unchanged).

Nissan moved 4% higher to 80, matching Mazda (unchanged), while the Chrysler nameplate climbed 7% to meet Cadillac, Buick, Kia and Mitsubishi at 79. Honda's Acura lost ground, falling 8% to 76 at the bottom of the category.

"Year-to-date sales are looking pretty flat, and demand for cars may slacken some," said VanAmburg. "But the good news for Detroit is that higher levels of customer satisfaction will make it more competitive."

Among domestic automakers, Ford kept its lead, stepping up to 84, followed by GM (81) and Fiat Chrysler (78). In comparison with foreign-made cars, which have long had the highest customer satisfaction, domestics are catching up, rising to 81 overall. European automakers also did better, matching Japanese and Korean manufacturers at 82.

The ACSI report was based on 3,776 customer surveys collected in the second quarter of 2016.

ACSI is described as "a national economic indicator of customer evaluations of the quality of products and services available to household consumers in the US and uses data from interviews with roughly 70,000 customers annually as inputs to an econometric model for analysing customer satisfaction with more than 300 companies in 43 industries and 10 economic sectors, including various services of federal and local government agencies.