NHTSA Complaint #11698051 — 2018 GMC SIERRA 1500 POWER TRAIN

Complaint Details

ODI Number	11698051
Vehicle	2018 GMC SIERRA 1500
Component	POWER TRAIN
Date of Incident	September 1, 2023
Date Filed	November 7, 2025
Mileage	N/A miles
Crash	No
Fire	No
Injuries	0
Deaths	0
Vehicle Towed	No
State	KY

Consumer Description

Repeated transmission issues with the 8 speed transmission due to the malfunctioning valve body. This has caused major safety issues and nearly killed my family with the vehicle locked up and wouldn’t shift on the interstate. The dealership did a warranty repair on the torque converter which made the symptoms slightly better until the vehicle was no longer covered by warranty, at which time all symptoms came back. GM knows their 8 speed transmission has an issue and hasn’t provided a solution. Now, due to the faulty valve body, I have to have my entire transmission replaced for $8000.

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