When it comes to keeping customers happy, dealerships for General Motors Company [NYSE:GM] brands Buick and Cadillac take top honors, according to the latest findings of a study conducted by J.D. Power. In the annual U.S. Customer Service Index study, Cadillac ranked highest among luxury brands for dealer service, while Buick was highest among mass market brands. Last year the titles went to Lexus and GMC, respectively.

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On a 1,000 point scale of customer satisfaction, Cadillac scored 872 points to beat 11 other brands eligible for the luxury category, while Buick scored 835 points to beat 18 other brands in the mass market category. Customers were least satisfied with the services of Land Rover dealerships in the luxury category and those of Ram in the mass market category. The results were particularly bad for Fiat Chrysler brands, with Dodge and Jeep also at the bottom of the mass market category.

More than 90,000 vehicle owners took part in the study, which was fielded between October and December 2013. And only franchised dealer facilities for maintenance or repair work were eligible.

Overall, the study shows that satisfaction is improving, when compared to the results of previous years. And in more specific fields, the study has shown that dealerships that use digital tablets during service interactions can have a positive impact on customer satisfaction.

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It should be noted that 68 percent of luxury vehicle owners and 46 percent of mass market brand owners indicated that their vehicle was covered under either a complimentary or prepaid maintenance package during the first year of ownership, which is significantly higher than just a few years ago. These tend to create a long-term relationship between the customer and dealership, which, when coupled with satisfying service experiences during that period, can have a very positive impact on loyalty rates, according to researchers.

2014 J.D. Power Customer Service Index - Luxury Brands

1) Cadillac - 872
2) Audi - 868
3) Lexus - 867
4) Infiniti, Lincoln - 865
Luxury Brand Average - 855
5) Jaguar - 853
6) Porsche - 848
7) BMW, Mercedes-Benz - 847
8) Acura - 843
9) Volvo - 840
10) Land Rover – 805

2014 J.D. Power Customer Service Index - Mass Market Brands

1) Buick - 835
2) Volkswagen - 830
3) GMC, MINI - 828
4) Chevrolet - 812
5) Toyota - 801
6) Chrysler - 799
7) Hyundai - 798
8) Nissan - 797
Mass Market Brand Average - 797
9) Kia - 796
10) Mitsubishi - 794
11) Honda - 792
12) Ford, Mazda - 791
13) Scion - 780
14) Subaru - 776
15) Dodge - 765
16) Jeep - 756
17) Ram - 752

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