I purchased this vehicle on November 23, 2023, with 138,122 miles on it. I’ve added only about 50,000 miles, and in that short time, I’ve had one major component after another fail — well beyond what any reasonable owner should experience.
Here’s the timeline:
2024: The engine failed and had to be replaced. While the part was covered, I still paid $7,000 in labor costs out of pocket.
2025 (current): The transmission is near failure — slipping, jerking, and shifting erratically. Multiple technicians have confirmed it’s on its last legs, and quotes range from $7,000 to $10,000 to repair or replace it.
Ongoing: The truck also has intermittent electrical issues that no shop has been able to diagnose or permanently fix. The problems appear periodically, affecting systems at random and creating additional downtime.
After researching, I discovered that GM’s 8L90 8-speed (CPA GEN1) transmissions have a well-documented history of shuddering, harsh shifts, and premature failures, even leading to a class-action lawsuit. The symptoms described match what I’m seeing exactly.
I’ve done everything I can to maintain this truck responsibly, but these repeated and overlapping failures have made it financially impossible to keep up. Between the engine, transmission, and electrical issues, I’ve already invested heavily just to keep this vehicle running.
I purchased this vehicle on November 23, 2023, with 138,122 miles on it. I’ve added only about 50,000 miles, and in that short time, I’ve had one major component after another fail — well beyond what any reasonable owner should experience.
Here’s the timeline:
2024: The engine failed and had to be replaced. While the part was covered, I still paid $7,000 in labor costs out of pocket.
2025 (current): The transmission is near failure — slipping, jerking, and shifting erratically. Multiple technicians have confirmed it’s on its last legs, and quotes range from $7,000 to $10,000 to repair or replace it.
Ongoing: The truck also has intermittent electrical issues that no shop has been able to diagnose or permanently fix. The problems appear periodically, affecting systems at random and creating additional downtime.
After researching, I discovered that GM’s 8L90 8-speed (CPA GEN1) transmissions have a well-documented history of shuddering, harsh shifts, and premature failures, even leading to a class-action lawsuit. The symptoms described match what I’m seeing exactly.
I’ve done everything I can to maintain this truck responsibly, but these repeated and overlapping failures have made it financially impossible to keep up. Between the engine, transmission, and electrical issues, I’ve already invested heavily just to keep this vehicle running.
- Bill H., Alexandria, US