— A GM 8-speed transmission lawsuit alleges several Cadillac, Chevrolet and GMC models are equipped with defective Hydra-Matic 8L90 or Hydra-Matic 8L45 transmissions.
The General Motors 8-speed transmissions allegedly "slip, buck, kick, jerk, harshly engage, suffer abnormal internal wear, sudden acceleration, delay in downshifts,delayed acceleration, difficulty stopping the vehicle, and eventually require replacement of the transmission or its components."
The 8-speed transmission lawsuit includes these models.
- 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
- 2016-2019 Cadillac CTS, CTS-V
- 2016-2019 Cadillac CT6
- 2015-2019 GMC Sierra
- 2015-2019 GMC Yukon, and Yukon XL, and Yukon Denali XL
- 2017-2019 GMC Canyon
The plaintiffs claim the transmissions cause safety hazards and expensive repairs once the 8-speed transmissions fail.
According to the lawsuit, the shuddering, shaking, jerking and hesitation comes from internal problems within the transmission and/or torque converter.
This allegedly causes friction and problems with the hydraulic systems and gears, which in turn results in metal shavings being circulated throughout the transmission.
Customers are allegedly stuck with ongoing transmission and torque converter repair expenses, including the need to flush the metal shavings from the transmissions.
GM 8-Speed Transmission Shudder Bulletins and Complaints
The lawsuit alleges more than 60 technical service bulletins (TSBs) and updates allegedly show the automaker knew about transmission shuddering and other problems since at least September 2014, including the following bulletins.
14628 / 14-07-30-001 / 14876 / 15-NA-007 / PIP5337 / PIE0353 / 16-NA-014 / 16-NA-019 / 16-NA-175 / PIP5405 / 16-NA-213 / PIP5437 / 16-NA-411 / 16-NA-404 / PIE0405 / 16-NA-361 / 18-NA-177 / 18-NA-235 / 18-NA-356
The transmission lawsuit also references multiple complaints, including these two from 2015 Chevrolet Corvette owners.
"8 speed automatic transmission down shifts at a stop with such force it feels as you have been hit from behind by another car while coming to a stop. Transmission also will not always engage properly and will over rev and slam into gear possibly causing an accident. Transmission at times will disengage while going forward then slam into gear with great force."
The Illinois owner alleges a GM insider said the automaker was aware some transmissions are defective and is working on a kit to fix the fluid starvation problem internally but has done nothing to inform owners of the potential dangers of erratic shifting.
"8-speed automatic transmission always shifts erratically when starting out cold (lazy shift, slow shift, etc.) and occasionally does not downshift when car comes to a stop, only to slam hard into 1st when gas pedal is pressed to resume travel. Dealer says GM claims this is "normal," but no car I've ever owned behaves like this. Appears to be fluid starvation internally."
The class action lawsuit says General Motors should stop selling all the vehicles and replace all the 8-speed transmissions with new non-defective transmissions.
The plaintiffs also want the judge to order GM to reform its warranties and they demand the automaker recall the vehicles.
Additionally, the plaintiffs argue owners should be awarded "actual, compensatory, exemplary, and statutory damages, including interest, including damages for economic loss including loss of the benefit of the bargain, overpayment damages, diminished value and out-of-pocket losses."
The GM 8-speed transmission lawsuit was filed in the U.S. District Court for the Eastern District of Michigan, Southern Division: Harper, et al., v. General Motors, LLC.
The plaintiffs are represented by Cohen Milstein Sellers & Toll PLLC, Gordon & Partners, P.A., Berger Montague PC, Capstone Law APC, The Miller Law Firm, P.C., Kessler Topaz Meltzer & Check, LLP, LLP, Keller Rohrback L.L.P., and Pitt, McGehee, Palmer & Rivers, P.C.