2021 Chevrolet Tahoe: transmission slipping

Filed Aug 13, 2026 · Transmission · IN

The automatic transmission on my 2021 Chevrolet Tahoe (gasoline engine, 10-speed 10L80 transmission) has been exhibiting intermittent slipping/skipping during gear changes, particularly during acceleration and deceleration. The transmission component is available for inspection upon request. The malfunction poses a safety risk as the unexpected hesitation and rough shifting creates unpredictable vehicle behavior at highway speeds and during merging, increasing the risk of a collision with other vehicles. The problem has not yet been formally confirmed by a dealer or independent service center, however a knowledgeable automotive advisor has assessed the likely cause as moisture contamination of the transmission fluid, which degrades lubrication and causes erratic shifting behavior, known issue in several GM vehicles, but the only recall related to this issue is for just Diesel vehicles. I contacted General Motors customer service regarding this issue and was directed to file this complaint with the federal safety agency, as GM stated they were unable to attach or create a related existing recall to my vehicle. The vehicle has not been inspected by police, insurance representatives, or the manufacturer at this time. I am in the process of scheduling service at a transmission specialist. No warning lamps or dashboard messages appeared prior to or during the shifting malfunction. Symptoms first became noticeable at 85,000 miles, and have continued since.

Filed Aug 30, 2025 · Electrical, Engine · FL

The affected components are the electrical system, engine, and power train. In March 2025, my 2021 Chevrolet Tahoe displayed multiple warning lamps across the dash, including traction control and check engine lights. The vehicle shifted erratically and sometimes entered limp mode. I brought the vehicle to AutoNation Chevrolet South Clearwater for inspection. The dealer replaced the battery, dismissed my concerns, and stated that a test drive was performed, but the mileage in and out on the invoice was identical, showing it never actually occurred. Diagnostic trouble codes (P0700, P0717, P2714, P2716, P0706, and multiple U-codes) were present but were not fully investigated. A GM Technical Service Bulletin (21-NA-149, December 2022) covers these exact symptoms (caused by engine wiring harness chafing), but it was never referenced or applied. Because the problem was not addressed, the condition worsened. By July 2025, the vehicle suffered a complete transmission failure. At that point, the dealer confirmed the issue, documenting transmission slipping, shuddering, noise, and additional codes (P0700, P077C, P17F6, P17FB, P1872). GM increased its goodwill contribution from 15% to 40% of the $9,925 repair cost, while AutoNation offered only $500 despite their role in the missed diagnosis. Safety Risk: My family and I were at risk each time the vehicle stalled, lost power, or shifted erratically while driving, including at highway speeds. These failures created a significant risk of collision. The drivability problem was not properly confirmed in March 2025 despite multiple codes being present. By July 2025, the dealer acknowledged and confirmed the transmission failure. The vehicle remains available for inspection, and I have retained all invoices, diagnostic reports, and communications with GM and the dealership.

Filed Jul 25, 2025 · Engine · TX

I’m reporting a transmission failure that occurred unexpectedly on my 2021 Chevy Tahoe/the diesel version has been recalled so I don’t know why all the other 2021 Tahoe have not been recalled for this issue . The vehicle began shifting roughly and slipping between gears, followed by a warning message and eventual inability to shift properly. I had it inspected by a family friend who owns a body shop , and I was told the transmission needs to be replaced at a cost of nearly $7,000. I am no longer under powertrain warranty, but this failure feels premature and unsafe for such a new vehicle. I’ve seen many other 2021 Tahoe owners report similar issues online including transmission failure, harsh shifting, valve body problems, and complete breakdowns . This seems like a pattern, and I believe it may warrant investigation. I’m asking the federal safety agency to investigate whether this is part of a broader transmission defect that poses a safety or reliability concern. Sudden shifting issues and inability to accelerate or reverse are dangerous for drivers and passengers. Thank you for your time and attention to this matter.

Filed May 1, 2025 · Transmission · VA

i have a 2021 Tahoe with 68,000 miles on it. On March 14 my transmission started slipping while driving. the RPM would rev up, the car would jerk forward and then the RPM would fall back down. did this to me 6 times while driving. i got my car home, called the dealership. went to drive it to the dealership and the car would no longer go in reverse. had to have the car towed to the dealership.

Filed Apr 3, 2025 · Engine, Transmission · FL

I was driving along the highway at 11pm when I the vehicle started shaking and I heard strange sounds coming from outside the vehicle. I pulled over to inspect and realized it was coming from the engine bay. The engine was making knocking, rattling, and belt slipping noises and the entire vehicle was shaking and the engine also stuttering. I was able to drive the vehicle to a nearby plaza where I had it towed the following morning. There were no warning signs, the vehicle ran properly up until this occurred. The dealership inspected it and told me the engine needs to be replaced and it was likely that a rod bearing that went bad. This happened nearly 2 months ago and I am still waiting for a new engine.