While customer service is typically strong at all auto dealers, service after the sale can tell a different story. And the more you pay for a vehicle, the better you expect post-sale service to be.

According to the latest results from J.D. Power’s U.S. Customer Service Index (CSI) study, the luxury brand offering the best service is Lexus from Toyota Motor Corp. (TM). Among mass market brands, Buick from General Motors Co. (GM) leads the pack.

Satisfaction with a dealer’s service operation is a leading factor in developing customer loyalty to a brand (or an automaker), and loyalty is what determines whether a dealer has a repeat customer in a few years.

The J.D. Power CSI is based on five metrics: service initiation, vehicle pickup, service facility, service quality and service advisor. The 2017 study is based on responses from more than 70,000 owners and lessees of 2012 through 2016 model-year vehicles and was fielded between October and December of 2016.

Some general observations before we get to the rankings:

  • Service advisors generated the highest level of satisfaction (an index score of 835 out of a possible 1,000), followed by service initiation (832), vehicle pickup (810), service quality (809) and service facility (794).
  • Customers rated dealers higher than non-dealers on 15 of 16 attributes with amenities, waiting area comfort and cleanliness being the most often mentioned. Non-dealers outscored dealers only on time required to complete the service, and then by just a fraction of a point.
  • Getting it right the first time pays big dividends. Some 94% of customers said the dealer fixed it properly the first time. For the 6% who reported worse results, the satisfaction rating dropped by an average of 184 index points.

Among luxury vehicles, the average CSI score was 859. Ford Motor Co.’s (NYSE:F) was the highest-ranked U.S. brand, and both it and Cadillac were among the top five in the luxury category. Here are the 12 luxury brands J.D. Power reported:

  1. Lexus: 874
  2. Audi: 869
  3. Lincoln: 868
  4. Porsche: 867
  5. Cadillac: 865
  6. Jaguar: 864
  7. Mercedes-Benz: 864
  8. Infiniti: 861
  9. BMW: 852
  10. Acura: 836
  11. Volvo: 836
  12. Land Rover: 828

Among 19 mass market brands included in the survey, the average score was 807. Fiat Chrysler Automobiles N.V. (FCAU) claimed the bottom four places in the rankings. Its highest-scoring Chrysler brand even failed to reach the mass market average. Here’s J.D. Power’s list:

  1. Buick: 860
  2. Mini: 850
  3. GMC: 837
  4. Chevrolet: 829
  5. Nissan: 822
  6. Kia: 818
  7. Subaru: 818
  8. Toyota: 815
  9. Volkswagen: 814
  10. Hyundai: 812
  11. Honda: 797
  12. Ford: 796
  13. Mitsubishi: 793
  14. Chrysler: 785
  15. Mazda: 784
  16. Dodge: 771
  17. Ram: 755
  18. Jeep: 753
  19. Fiat: 739