According to GM Authority, via Classaction.org, a group of owners for several of General Motor's most popular rear-wheel-drive vehicles have filed a class action lawsuit again the automaker over supposed defects in the vehicles' eight-speed automatic transmission. Drivers claim they are experiencing violent shakes, jerks, or a "hard shift" when selecting a gear.
Furthermore, a total of 13 technical bulletins have been filed regarding this specific gearbox and none of them have fixed the problems so far. Which vehicles are affected? Well, the ones that be equipped with this transmission.
They include the following:
• 2015-2019 Chevrolet Silverado
• 2017-2019 Chevrolet Colorado
• 2015-2019 Chevrolet Corvette
• 2016-2019 Chevrolet Camaro
• 2015-2017 Cadillac Escalade and Escalade ESV
• 2016-2019 Cadillac ATS and ATS-V
• 2016-2019 Cadillac CTS and CTS-V
• 2016-2019 Cadillac CT6
• 2015-2019 GMC Sierra
• 2015-2019 GMC Yukon and Yukon XL
• 2017-2019 GMC Canyon
If you're the owner for any of the above vehicles, then you may know exactly what we're talking about here. The report claims the problem occurs most often when a driver accelerates or decelerates and the transmission shifts a gear. Many drivers complain of a hesitation, then a shudder or even a jerk during the gear change.
What's more, some owners have even complained the issue has occurred within a single gear. But don't think for a moment this is just some minor shake or vibration. It's sometimes far from it. The report claims some drivers have said the shaking can get so violent it feels like another car has hit them. There was even the case of one owner who claimed that moving from the "reverse" to "drive" gear was so violent that the car nearly drove through their garage door. Even more troubling, the National Highway Transportation Safety Administration has received several complaints about this transmission as well, so it's not like this is suddenly a new problem.
The class-action lawsuit states the exact problem could involve the torque converter because it's being exposed to undue friction. There was one NHTSA complaint that noted a failed torque converter in a GMC Canyon after only 16,000 miles. Again, the torque converter may not be the precise cause, but it's certainly a good place to start an investigation. In the meantime, GM will need to respond to the class action suit and, hopefully, affected owners will finally start getting some answers.