J. D. Power's latest awards are in, and when it comes to customer service, Buick is number 1. At least among mass-market brands.

The annual Customer Service Index study looks at the customer experience when they're at the dealer. And it measures who is doing the best job of keeping customers happy in the service bay, surveying owners who have taken their vehicles in for service or repair. On the chart of mass-market brands, Buick was number one. It's their third year in a row in the top spot and the brand has had the highest score four out of the last five years.

Buick's score of 857 out of 1,000 put it ahead of Mini, Mitsubishi, Chevrolet, GMC, and Toyota.

Luxury brands were ranked separately, with Porsche in the top spot with 893 points. Cadillac was a close third with 880. Lexus was in second with 881.

Some other insights from the study showed that about a third of customers prefer to use text message for their service appointments. Something that dealers do only nine percent of the time. Customers also, not surprisingly, value helpful advice from their service advisor, as well as being informed about the work done.