Two American Car Brands Just Saw the Biggest Drop in Customer SatisfactionAutoblogKarl FurlongMon, September 21, 2026 at 1:45 PM UTCAdd us on GoogleAutoblog and Yahoo may earn commission from links in this article.Many car buyers looking for a premium or luxury model rightfully expect those vehicles to be more satisfying to own than mainstream alternatives. After all, they're more expensive in many cases. But a more desirable badge doesn't always mean you're getting a more satisfying vehicle, and the latest American Customer Satisfaction Index (ACSI) demonstrates this. Toyota emerged as the most satisfying brand, a result that won't surprise many, but what caught our eye were the sharp declines for Cadillac and Buick in the 2026 study.Cadillac and Buick See Biggest Declines2026 Cadillac Escalade Sport PlatinumCars & BidsView the 2 images of this gallery on the original articleAdvertisementAdvertisementIn this year's vehicle satisfaction study, all automakers combined registered a decline of 1% versus 2025. Mass-market brands dropped by 1% and luxury nameplates were down by 3%. Among individual automakers, Buick and Cadillac saw the most significant losses relative to 2025.2025 Score2026 Score% ChangeBuick8168-16%Cadillac8169-15%All mass-market nameplates7978-1%All luxury nameplates8078-3%Buick, which fits into the mass-market segment but is generally perceived as a more upscale brand, was one of the worst performers in 2026. Only Chrysler had a lower score, at 67. Cadillac was the lowest-ranked luxury brand.This fall from grace for two major General Motors brands is unexpected. Two other brands from the GM stable—GMC and Chevrolet—also saw declines that were worse than the industry average.What The Study Tracks2026 Buick EnclaveBuickThe ACSI looks at multiple metrics related to the car ownership journey. This includes seating comfort, performance, dependability, technology, gas mileage, and trade-in value. It even considers owners' experiences with related mobile apps and websites. The study does not indicate ratings by automaker or model, though, so it's not possible to know exactly where Buick and Cadillac fell short or what contributed to their disappointing 2026 scores.AdvertisementAdvertisementTo see if the GM brands' drop in satisfaction was mirrored elsewhere, we looked at the results of the JD Power Initial Quality study too, which came out earlier this year. In it, Cadillac dropped from 18th to 25th between 2025 and 2026, while Buick improved from ninth to sixth over the same period. Cadillac was almost the lowest-ranked overall brand in the 2026 version of this study, closely mirroring the ACSI results. It wasn't all bad news for GM, as Chevrolet joined Buick in the top 10 this year.Cadillac, which has an extensive electrified lineup, does seem to be struggling with more quality issues in recent years.Related: BMW Vs. Cadillac Reliability: Neither Can Catch Lexus, But One WinsWhat It Means2025-2026 Cadillac Lyriq in Argent SilverCadillacWhile rivals like Ford have made significant improvements in new-vehicle quality in recent months, GM has some way to go. Between the ACSI and JD Power results, quality and owner satisfaction have slipped for certain GM brands, particularly Cadillac. For legacy automakers, maintaining quality standards as cars shift to software-defined designs has been challenging. These vehicles may still be solidly built, but infotainment and other software-related glitches have often soured the experience.Related: Cadillac Vs. Lincoln Reliability: Only One American Brand Can WinThis story was originally published by Autoblog on Sep 21, 2026, where it first appeared in the News section. Add Autoblog as a Preferred Source by clicking here.