GM Will Face Class Action Suit Over 8-Speed Gearbox Issues

A federal judge certified a class-action lawsuit against GM Monday in regard to claims the automaker knowingly sold defective transmissions in around 800,000 cars.

U.S. District Judge David Lawson green-lit class actions on behalf of 39 plaintiffs from 26 states in the Eastern District of Michigan. The lawsuit is over allegedly defective automatic transmissions used in eight GM products—including the Corvette, Camaro, and others—between 2015 and 2019.

In the 60-page decision published by the court Monday, Lawson ruled that a number of group lawsuits against GM would be the most efficient way to tackle the volume of plaintiffs allegedly experiencing issues. The court confirmed that owners in each of the 26 states had experienced common problems with their 8L45 or 8L90 eight-speed automatic transmissions. The 8L45 and 8L90 transmission came installed in a wide variety of GM products, including the brand’s full-size SUVs and pickup trucks, as well as many of the automaker’s performance-oriented models. The following vehicles are listed as affected in the lawsuit:

• 2015-2019 Chevrolet Silverado

• 2017-2019 Chevrolet Colorado

• 2015-2019 Chevrolet Corvette

• 2016-2019 Chevrolet Camaro

• 2015-2019 Cadillac Escalade and Escalade ESV

• 2016-2019 Cadillac ATS, ATS-V, CTS, CT6 and CTS-V

• 2015-2019 GMC Sierra, Yukon, Yukon XL and Yukon Denali XL

• 2017-2019 GMC Canyon

According to complaints detailed in the lawsuit, drivers allegedly experienced harsh shift patterns including lunging, lurching, or general hesitation during acceleration and deceleration. Some even likened the sensation to being rear-ended by another vehicle. Furthermore, a second transmission issue became apparent at highway speeds, where vehicles would allegedly shudder and shake. The plaintiffs point to improper ATF formulation and valve body design issues as the root of the problem.