NHTSA Complaint #11692234 — 2021 GMC SIERRA 1500

POWER TRAIN issue reported to NHTSA

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Complaint Details

ODI Number	11692234
Vehicle	2021 GMC SIERRA 1500
Component	POWER TRAIN
Date of Incident	October 7, 2025
Date Filed	October 8, 2025
Mileage	N/A miles
Crash	No
Fire	No
Injuries	0
Deaths	0
Vehicle Towed	No
State	MN

Consumer Description

Transmission on my vehicle has failed three times since I bought the vehicle in October of 2021. Vehicle currently has 39,000 miles. First transmission issue was resolved by the dealership by replacing the transmission valve body. This solved the problem for approximately 12,000 miles. In September of 2025 with 39,000 miles the transmission suffered a catastrophic breakdown which lead to complete transmission replacement. After being “fix” the vehicle suffered another catastrophic transmission failure within 400 miles of the complete transmission replacement. This incident caused the vehicle to shut completely down and I was stuck in the traffic lane of the US Highway. Fortunately my vehicle and I were not struck while waiting 30 minutes for a tow truck. Presently the vehicle is back at the dealership awaiting repair. From my review of available on-line information it appears there are 10’’s of thousands of GMC Sierra pickups with major transmission issues. This needed to be addressed before someone is killed due to the poor quality of these GMC trucks.

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