David Lawson, U.S. District Judge for the Eastern District of Michigan, has granted class certification for lawsuits against automaker GM and their faulty 8-speed transmissions.

The class action certification comes after at least 39 plaintiffs across 26 states accused the automaker of knowingly selling vehicles that had this faulty transmission.

Ted Leopold, a representing attorney and partner at Cohen Milstein law firm, contends, “General Motors knowingly sold over 800,000 eight-speed transmission vehicles, which they knew to be defective for years, and yet made the business decision not to tell its customers before purchase." Leopold adds, "Dealers were directed to tell the customers that harsh shifts were ‘normal' or ‘characteristic.’ Such decision-making is both highly irresponsible and emblematic of what GM believes it can get away with."

Owners of impacted vehicles explain in the suit that as they drive, they experience "a hesitation, followed by a significant shake, shudder, jerk, clunk, or 'hard shift' when the vehicle's automatic transmission changes gears." According to the lawsuit, this erratic transmission behavior makes the impacted vehicles unsafe to drive. It's not yet clear whether there have been any injuries or accidents as a result of the faulty transmission.

The faulty transmission impacts a number of GM vehicles that have one or two models of automatic transmissions installed on them. These models, the GM GL90 or 8L45, were fixed on select vehicles made between 2015 and 2019. Impacted vehicles include Chevrolet’s Silverado, Corvette, and Camaro. Cadillac models impacted include the Escalade and Escalade ESV, ATS, ATS-V, CTS, CT6, and CTS-V. GMC models include the Sierra, Yukon, Yukon XL, Yukon Denali XL, and Canyon.

The lawsuit also highlights that since 2015, the automaker has issued at least 13 technical service bulletins alerting consumers about the shifting issues.

Under this certified class action lawsuit, an estimated 800,000 owners of impacted vehicles could be affected.

According to a release issued by Cohen Milstein, GM has pushed back saying that what it allegedly “‘concealed’ to customers cannot be resolved on a class-wide basis because ‘public knowledge about the defect varied throughout the relevant class period.’ The lawsuit also highlights that judge Lawson's oversight of the case revealed that GM’s defense was “‘disingenuous considering the defendant’s recent efforts to conceal from public disclosure vast portions of the record offered by the plaintiffs to show the existence of the defect and the defendant’s historical knowledge of the same.’”

In the lengthy 60-page decision, Judge Lawson points to a class action certification as being the best way to tackle the mounting lawsuits against GM. Prior to certification, all the lawsuits argued similar claims that GM implemented improper ATF formulation and a poor valve body design that resulted in the transmission issues.

Plaintiffs in the class action lawsuit are seeking restitution or reimbursement for their defective vehicles in conjunction with any other maintenance fees they had to pay because of transmission issues. GM has not yet issued a statement pertaining to the transmission problems or the class-action certification.