Just when things seemed to be on the up and up for the Corvette, an older issue is coming back to strike. Allegedly, GM models from 2015 to 2019 ( like C7) have transmission problems that make the trucks dangerous to drive and never received an effective solution.

We’ve been following and reporting on the C7 Corvette for having transmission problems for months, but the issue is larger than expected. It includes multiple General Motors vehicles equipped with possibly faulty eight-speed automatic transmissions.

Specifically, the units involve the General Motors 8L90 and 8L45 eight-speed automatic transmissions built between 2015 and March 1, 2019. Both units have a lot in common, but the 8L45 is a lighter unit used in fewer options.

The more robust 8L90 is more popular, and both are designed for front, rear, and AWD applications.
The lawsuit alleges erratic transmission behavior makes vehicles unsafe to drive.

A judge granted class-action status to the lawsuit, representing 39 plaintiffs across 26 states.
Drivers of the Chevy Silverado and other GM vehicles report transmission hesitation, shaking, shuddering, clunking, and hard shifts upon changing gears.
Vehicle models in the lawsuit include:

• 2015 – 2019 Chevy Silverado 1500
• 2017 – 2019 Chevy Colorado
• 2015 – 2019 Chevy Corvette
• 2016 – 2019 Chevy Camero
• 2015 – 2019 Cadillac Escalade and Cadillac 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

• Reportedly, General Motors didn’t do enough to solve the transmission problems found in Chevy Silverado models and other vehicles.
Claims report that General Motors has released 13 different technical service bulletins related to the issue shifting issue alone since 2015.
• So, technicians had 13 different things to try. Some of the bulletins recommended changing the transmission fluid, replacing the torque converter, providing a software update, removing the transmission pan, replacing the transmission cooler bypass valve (TBV), and more.
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• But older technical service bulletins from 2017 and earlier report that the cause of the transmission problems is unknown and that General Motors was working on finding the cause and providing a solution.
• Cohen Milstein partner, Ted Leopold, is the court-appointed lead counsel on the case and shared that General Motors knowingly sold over 800,000 vehicles equipped with faulty eight-speed automatic transmission units despite being aware of the defects.
• The business decision to not tell customers before their purchase was made. Allegedly, dealers were instructed to tell customers that the hard shifts were normal and characteristic. Ted shared that this decision-making is highly irresponsible and emblematic of that General Motors believes it can get away with.
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• Did the A8 transmission problems ever get corrected?
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• The GM vehicles didn’t exactly receive a fix for the transmission problems. But it gets a new eight-speed automatic transmission when it was redesigned for 2019. In 2023, GM started replacing the transmission control module and reprogramming the software.
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• There hasn’t been any clear indication if this fixed the problem. Also, if you had a 2015 model with issues, then waiting until 2023 for a potential fix is a long time.
• There was a recall related to a driveshaft issue in 2020 that could send vibrations through the transmission as well.


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