The feeling is familiar to anyone who has driven a 2017 Silverado for a sufficient amount of time. As you ease onto the throttle and drive through a parking lot at a slow speed, the vehicle abruptly trembles as if it has struck a section of imaginary rumble strips. It lurches after that. After then, it settles. For almost ten years, drivers have been experiencing this identical feeling, and for the majority of those years, GM dealers have a well-known reaction. It’s common. With a straight face, they would say that, return the keys, and let the customer go.
One of the biggest automotive class action lawsuits in recent memory is around the word “normal.” The plaintiffs in the GM transmission lawsuit claim that the automaker continued to sell cars with the system from 2015 to 2019 despite knowing that its 8L45 and 8L90 eight-speed transmissions had a faulty torque converter and that the shudder was being caused by metallic debris contaminating the transmission fluid. Yukons, Cadillacs, Camaros, Corvettes, Escalades, and Sierras. The list resembles a tour of GM’s most lucrative nameplates.
| GM Transmission Lawsuit — Key Information | Details |
|---|---|
| Defendant Company | General Motors |
| Headquarters | Detroit, Michigan |
| Transmissions Involved | 8L45 and 8L90 eight-speed automatics |
| Manufacturer of Transmissions | GM Powertrain |
| Affected Model Years | 2015 – 2019 |
| Affected Brands | Cadillac, Chevrolet, GMC |
| Notable Models | CT6, Escalade, Camaro, Corvette, Silverado, Sierra, Yukon |
| Reported Issues | Shudder, jerking, hard shifting, hesitation |
| Suspected Root Cause | Faulty torque converter |
| Court Status (June 2025) | Class action decertified by 6th U.S. Circuit |
| Future Litigation | Smaller localized lawsuits expected |
| Ongoing Investigation | 10-speed transmission complaints under review |
| Consumer Resource | BBB Auto Line |
The nationwide class action was then decertified by the 6th U.S. Circuit Court of Appeals in June 2025. It was a significant success for GM, the kind of legal triumph that is celebrated quietly in a Detroit boardroom as opposed to being publicized. The court accepted GM’s contention that the impacted owners’ disparate states, repair histories, and damages prevented them from being considered as a single group. The case was returned to the lower courts, where it will probably break up into smaller, local disputes. less dramatic. more difficult to overlook over time.
Decertification may have been the most astute move made by GM’s legal team throughout the whole affair. In an afternoon, a single nationwide class action can result in a billion-dollar verdict. Twenty smaller lawsuits, dispersed around federal districts, are settled one at a time, frequently in secret, with non-disclosure agreements that conceal the worst aspects of the public record. Observing how automakers handle these instances gives the impression that fragmentation is nearly as important as complete triumph.
However, the court’s decision did not end the owners’ shaking. Drivers who have had transmission flushes performed two, three, or four times continue to complain on forums like GM-Trucks.com and Corvette Forum. Six months after having their torque converters changed under warranty, some people are still experiencing the shudder. Others paid for their own repairs—a Cadillac CT6 transmission repair can cost up to $4,000—and are now unsure if they would ever receive any compensation.
Investigations are already underway into the 10-speed transmissions, which are thought to be the replacement for the problematic 8-speeds. Lawyers are swarming about. We are keeping track of complaints. It’s still unknown if those issues will lead to another full-fledged lawsuit, but the pattern seems similar enough that it’s difficult not to anticipate more legal action by 2027 or 2028.
For its part, GM keeps doing what big automakers always do in court. It continues to produce the next generation of vehicles while denying any wrongdoing and citing technical service bulletins. One of the best-selling cars in America is still the Silverado. Cadillac’s lineup is still anchored on the Escalade. Every morning, hundreds of thousands of cars’ cabins tremble from the tremor that still exists someplace. Patience, proof, and the owners’ determination to continue battling will determine whether the minor lawsuits succeed where the larger one failed. Some people will. Some people are worn out. Detroit is hoping for the latter.
