GMC Complaints

This complaint involves a sudden failure of my vehicle’s Anti-Lock Braking System (ABS) and Forward Collision Warning system, both of which are critical safety systems. While driving my [XXX] son to school, multiple warning lights suddenly appeared on the dashboard without any prior indication of a problem. The vehicle displayed a warning message instructing me not to exceed 36 miles per hour, and several system alerts activated simultaneously, my ABS brake system failed and a transmission failure warning. These issues appeared suddenly while the vehicle was in normal operation. Prior to this incident, the vehicle had been functioning perfectly. The evening before, I had driven the vehicle to pick up my son from wrestling practice with no issues. The following morning, during a routine trip to school, these critical safety warnings appeared without warning. Because the warnings involved the braking system, I immediately took the vehicle to Beach Buick GMC for inspection. The dealership diagnosed the issue as a software failure affecting the braking system and informed me that the vehicle required a software update and system download in order to restore proper operation of the brakes and related safety systems. I was required to pay over $300 for this repair because my vehicle is approximately 3,000 miles outside of the warranty period. However, I believe a failure involving the braking system and safety warnings should not occur suddenly in a properly functioning vehicle and should not be treated as a normal maintenance expense. I contacted **General Motors customer service to ask why a failure involving a critical safety system would not be covered or investigated further. The only explanation provided was that the vehicle was outside of the warranty period. I requested a written explanation of their decision for my records, but I was told that providing written explanations is against company policy. I have more to say but I am out of characters... INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMA

Following the remedy of the engine recall in 2025, the truck started having intermittent electrical issues (i.e. warning lights on dash turn on/off: service 4WD, Loss traction Control, etc) come one while the truck is being driven. If the truck is turned off while the dash warning lights are on, it will NOT Start for about 24 hours. If the warning lights are ignored, eventually they will go off on their own. Additionally, the truck is having "no-start" problems (randomly the truck does not start, then after a few days it starts). A New development, when backing up there is a scraping/squealing sound (possibly universal joint). Truck has been back to the dealership that replaced the engine block for the recall and they have failed to identify any issues as these problems are intermittent. Engine Recall Replacement Invoice (Attached)

[XXX] and [XXX] of 2025 the 6.2 V8 engine died while driving down the highway in Houston. The truck was bought brand new in January of 2025 with 100 miles on the odometer. The first engine failure happened [XXX] with 10,350 miles. Replaced, the second failure happened [XXX] with just under 25,278k miles. Once again the engine was replaced and took almost 6 weeks. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

driving 70mph on highway when engine suddenly failed. engine turned off and kicked into neutral. had to pull over on busy highway in a powerless car and have car towed. it is now getting a full engine replacement at 42k miles.

Transmission shudder that is causing Drivability issues. Multiple mechanics have told me to drive it and maintain it until the transmission gives out.

While driving down a highway doing between 45 and 55 mph the transmission suddenly and completely faulted causing the truck to come to a complete stop. Just enough power to get to the shoulder luckily. The transmission had basically completely blown out, fluid everywhere. The insurance company did not find any comprehensive damage. The entire transmission needs to be replaced. There were no indicators showing any problems, no alerts, no warning whatsoever. Mechanics said there was a lot of metal coming out of the transmission. The truck is currently in a mechanic shop awaiting the new transmission, so at this time it is available for inspection. The safety issue here is that it happened on a busy highway, and the vehicle was no longer drivable so it needed to be towed causing more time spent on the side of the road.

The 2019 GMC Sierra AT4 with the 6.2L V8 engine began making a rattling or tapping noise at 45 mph. No warning lights appeared on the dashboard. When starting the engine and idling, a similar noise can be heard from the engine. I bought the vehicle used from a dealership one month ago, with 80,000 miles, and the second issue is the complete failure of the blind spot warning system on both mirrors. It was a one-owner vehicle with a clean Carfax. I am scheduled to take the vehicle to the dealership's service department for a full inspection.

Sudden loss of propulsion at highway speed in lane of travel. Multiple vehicles almost ran into my vehicle as this was happening and alap afterwards, because I couldn’t get it out of the lane of travel all the way. It was towed to the dealer and determined to have a seized engine. There were zero lights or sounds preceding the loss of power. Safety recall N252494003 was performed at dealer in September 2025 and vehicle was deemed clear and safe.

Took it to dealer for engine sound said nothing was wrong 4 days later rod bearing went out while driving. Truck no longer able to drive

While driving several times smelt gas and car cut out engine came on and car stopped mid driving multiple times. Says they replaced fuel pump reset car etc