2020 Chevrolet Silverado 1500 transmission problems

Filed Nov 5, 2026 · Electrical, Transmission · FL

Q1: While driving my vehicle it started shifting very violently kind-of out of nowhere, without notice and did not resolve. This and many other factors, such as the diagnostic data retrieved from a nearby auto-parts store, lead me to believe this is likely due to an unresolved re-call on the vehicle that I just started receiving in the mail, the TCM Valve/Sensor. The vehicle is available for inspection upon request, at George Nahas Chevrolet, located in Wildwood, FL. Q2: My safety and that of others was severely impacted as it was indeterminate when the vehicle would violently over-rev and up or down-shift, while also leaving the possibility for the vehicle to just stall completely or to potentially have a total "rear wheel brake lock-up" scenario, as mentioned in the federal safety agency Re-Call. (N242454440 | RIONL-24V797-0912) This issue left me stranded and the vehicle was towed to a nearby GM Dealership, noted above. Q3: This issue was noted in third-party/independent diagnostic data (available upon request), prior to delivery of the vehicle to the dealership. Additionally, the issue was noted at the GM Dealership after four (4) months of repair attempts. The issue was re-encountered during a test drive when the dealership tried to return the vehicle to me un-repaired, demanding payment w/o invoice. The GM Certified Diesel Technician and I test drove the vehicle and found the issue to be the same or even worse. During this test drive, the GM Diesel Tech noted that the TCM could likely be one of the primary issues causing or contributing to the harsh shifting. Q4: The component was supposedly inspected and replaced by the dealership. However, the federal safety agency Re-Call is still showing as INCOMPLETE and the dealership will not provide me with an invoice or any data regarding this matter. The manufacturer was notified months ago and asked to provide data in relation to this matter, but still no resolution. Please let me know if you can inspect and/or assist in any way. Q5: No

Filed Nov 5, 2026 · Transmission · OH

The truck has a serious transmission issue where it either will not shift into gear or gets stuck in a gear. I’ve had several instances on the freeway in traffic where this happens and I’m unable to keep up with the flow of traffic and feared another vehicle would not be able to avoid a collision. I need to exit the freeway and turn the car off for it to reset. But it will often just do this failure again. It creates a very dangerous situation. GM is aware of this, and offered a special warranty repair, but for some reason they refuse to honor the warranty for my truck

Filed Nov 4, 2026 · Transmission · PA

ruck hesitated when shifting at lower speeds and created a hazard while driving. Transmission isssues are known to Chevrolet and nothing is being done about it. My son’s Chevy Colorado did the same thing in 08/26 (got fixed at a Chevy dealer and was reported to the federal safety agency). This needs to stop and needs to be further looked into with Chevy! I have receipts and proof if needed (keeps giving me an error when I try to upload it)

Filed Oct 30, 2026 · Brakes, Transmission · AZ

Truck has less than 30K miles with normal usage and rear axle was leaking onto the brake disk and brake pads. This could potentially have caused braking problems. The dealer noticed this problem during a routine oil change. Dirt had crusted on the leakage area and none of the fluid had leaked upon the ground and was therefore not noticed while in the garage. There was no obvious external warning that this issue existed. Have currently scheduled a repair with the dealer, which includes new brake pads and disk resurfacing.

Filed Oct 20, 2026 · Transmission · TN

Transmission started slipping for no reason around 100 thousand miles. All maintenance had been done no code was ever shown on dash no check engine light took it to 3 different places and had it tested all said the same thing they couldn't find anything wrong. Now its sitting at the shop and they are saying its the Transmission and it needs a new one.

Filed Oct 20, 2026 · Electrical, Transmission · AZ

1. Transmission Issue: Since purchasing the vehicle, I have experienced ongoing transmission problems. The transmission exhibits noticeable shifting issues, including delayed response, harsh/rough gear engagement, and erratic shifting behavior while driving. 2. Intermittent Electrical & Sound Failure: In addition to the transmission issue, the vehicle has developed a severe intermittent electrical malfunction. Without warning, all audio and electronic sounds in the cabin completely turn off ("go mute"). This includes the loss of interior warning chimes, system alerts, and the audible turn signal clicker. The system restores itself randomly ("goes back when it wants to"), making the issue unpredictable. Safety Concern: The sudden loss of audible turn signals and safety warning chimes presents a driver distraction and safety hazard while operating the vehicle on public roads.

Filed Oct 19, 2026 · Transmission · 60,000 miles · TX

The contact owns a 2020 Chevrolet Silverado 1500. The contact stated that while attempting to reverse at an undisclosed speed, the vehicle accelerated independently. The check engine warning light and transmission warning light illuminated. The vehicle was towed to a dealer, where it was diagnosed that the engine and transmission required replacement. e. The failure mileage was unknown.

Filed Oct 14, 2026 · Transmission · MI

What failed: The automatic transmission on my 2020 Chevrolet Silverado 1500 Custom 4WD, 2.7L turbo (VIN [XXX]). It has an intermittent shudder, a stuttering vibration felt through the truck, under light throttle and under load. The truck is in my possession and available for inspection on request. Safety risk: The shudder happens during acceleration and under load, when smooth power delivery matters most, such as merging or climbing grades. I tow a 20-foot camper in the summer, which puts the transmission under heavy load, and a driveline problem while towing raises the risk. No crash or injury has occurred. Confirmed by a dealer: Yes. On XXX, at 44,934 miles, Serra Chevrolet in [XXX] confirmed the transmission concern under GM service bulletin 20-NA-142, which the dealer confirmed applies to my VIN (repair order XXX). The technician performed a transmission fluid exchange as the recommended repair. I will update this report if the shudder returns. The technician confirmed the contaminated fluid from the factory. Manufacturer or others: The dealer submitted a goodwill request to GM, which GM declined, so I paid for the diagnosis and repair myself. No police or insurance inspection, since there was no incident. Warning lamps and symptoms: No transmission warning lamps or messages appeared. The only symptom was the shudder itself, which first appeared around XXX. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Oct 6, 2026 · Transmission · CA

My transmission was shuttering from about 10,000 miles to 67,000. I reported it multiple times to the dealership and they did nothing about it until the 67,000 mark when they finally replaced it. the new transmission started to downshift very hard as soon as I got it back from the dealer and it just got worse I took it back and they had diagnosed that it was bad. They are in the process of replacing the transmission, a second time which would be my third transmission They’ve had my truck for 36 days. Clearly, General Motors and the dealership cannot figure out how to get my transmission to work properly. It’s a danger to my family and those on the road if it fails while on the highway.

Filed Oct 6, 2026 · Engine, Transmission · 140,000 miles · TX

The contact owns a 2020 Chevrolet Silverado 1500. The contact stated that the engine was previously rebuilt. While driving at an undisclosed speed, the vehicle jerked and lost motive power, with several unknown warning lights illuminated. The vehicle was pushed to the side of the road and towed to an independent mechanic, who determined that the engine had low compression, and that the engine and transmission needed to be replaced. The manufacturer was notified of the failure by phone. The failure mileage was approximately 140,000.