Automatic Emergency Braking problems of the 2026 GMC Sierra 1500

While driving at approximately 60 mph on an open road with no obstacles present and no braking input, the rear wheels spontaneously locked up without warning. No brake pedal input. No warning light prior to the event. No obstruction in the road. The vehicle has been subject to an active manufacturer recall for rear wheel lockup due to transmission control valve failure. The dealer's own diagnostic system generated a report showing six active fault codes in the following days including lost communication with the brake system control module and transmission control module. These codes were not addressed on the repair order. The dealer attributed the lockup to an automatic emergency braking activation without diagnostic confirmation and performed no repair. The manufacturer's own internal bulletin dated January 22, 2026 acknowledges the exact fault codes present on this vehicle as a known defect. The dealer cited this bulletin to dismiss the concern while stating no problems exist. A persistent brake noise has been confirmed by two separate authorized dealers across three visits with no repair performed at any visit. The vehicle has required five dealer visits in 77 days of ownership with 1,729 miles. The defect remains unresolved and poses serious risk of loss of vehicle control at highway speed.

I am the owner of a 2026 GMC Sierra 1500 denali ultimate equipped with the 6. 2l v8 l87 engine (VIN: [xxx] ), purchased new approximately three months ago. I am filing this complaint proactively. I have experienced no engine failure or symptoms to date. However, I am filing based on a documented pattern of l87 engine failures in 2025 and 2026 production vehicles, confirmed by multiple gm dealership technicians, which suggests that the manufacturing defect underlying NHTSA recall 25v-274 may not have been fully resolved by gm’s stated production improvements dated June 1, 2024. Nhtsa recall 25v-274 (April 2025) covered 597,630 vehicles from model years 2021–2024 for catastrophic l87 engine seizure caused by connecting rod bearing failure and crankshaft defects. Gm excluded 2025 and 2026 model year vehicles based on a claimed manufacturing fix. However, multiple 2026 production vehicles have since experienced the same bearing failure at extremely low mileage. Open NHTSA investigation ea25007 is already examining vehicles outside the original recall window, and recall query rq26001 is investigating the adequacy of gm’s remedy. I am requesting that NHTSA consider expanding the investigation scope to include 2025 and 2026 model year vehicles. As a 2026 owner of a $90,000+ truck with the identical engine configuration, I believe my vehicle warrants inclusion in any expanded investigation or recall action. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).