2023 GMC Sierra 1500

1. The L87 Engine Loss of Propulsion failed and is available for inspection at the service department at Power Swain Chevrolet dealership, Fayetteville, NC. 2. I, other vehicles, cyclists, and pedestrians were at risk. That vehicle could have come down on the highway, causing a vehicle pileup, which could have caused mass casualties. 3. The problem is known; the service advisor informed me the vehicle's engine needed to be replaced. 4. There were absolutely zero warning lamps or My GMC app alerts to announce vehicle issues. I have attached the last two maintenance records I have on hand. I suspect the dealership will try to deny responsibility for repairs. An extended warranty most nearly means we expect it to break down and your safety is not our concern.

After driving my vehicle for a short period of time I stopped to go shopping. When I returned to my vehicle I started it as usual and the check engine light illuminated. I began driving and within 0.25 miles I received an info enter message that stated my vehicle would have reduced acceleration and to please drive safely. My engine fans became noticeably louder and ran the entire trip home (about 15 minutes). After pulling into my driveway I sat in the vehicle and listen to the fans continue to operate. Additionally, my OnStar system, WiFi, and navigation systems quit working. A P1098 Code was returned when using a diagnostic code device. Disconnecting the battery would cause the check engine light to extinguish and for the truck to operate without reduced acceleration; however, OnStar, navigation and WiFi would not work. After shutting off the engine and then restarting the check engine light would once again illuminate and the reduced acceleration message reappeared.

On 18 March 2026 I was driving at night at highway speed with my family (wife, [XXX] son, [XXX] daughter, and [XXX] son) when, without any warning, my 2023 GMC Sierra AT4 with 20,700 miles abruptly and violently shuddered and reduced speed from approximately 65 mph to 30 mph uncontrollably. Shortly after the initial speed reduction the vehicle presented simultaneous alerts that it was in "reduced acceleration mode", the "emission system control" had failed, and the that the check engine light was on. Although the vehicle claimed to be in reduced acceleration mode I was unable to prevent it from continuously slowing to 0 mph. I attempted to use the accelerator to move from the left lane of traffic to the right shoulder without causing an accident. However, the vehicle violently shuddered and would not accelerate or maintain speed. I managed to maneuver around traffic and stop the vehicle on the right shoulder. Due to the unlit highway and my family's emotional state after the incident, I determined the safest course of action was to attempt to get the vehicle to a nearby parking lot. After turning the vehicle off and back on, I managed to slowly drive with my flashers on (despite the vehicle continuing to violently shudder) approximately 1 mile to a Wal-Mart parking lot. Once there I noticed I received an email from OnStar Diagnostics that my vehicle experienced a significant engine malfunction with an associated P129F code. I coordinated for the vehicle to be towed to Bill Cramer Chevrolet GMC Inc in [XXX] the following day. My vehicle had no lights, messages, or symptoms of this issue prior to it occurring. The dealership replaced the fuel pump power control module under warranty, cleared the faults, test drove the vehicle, and returned to me on 31 March 2026. The dealer mentioned they service roughly two vehicles of similar make and/or models daily for the same issue. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

While driving home from Phoenix on Hwy 95, 30 Miles out of Tonopah on the way to Reno engine propulsion and the complete engine failure occurred while driving at 75 mph. No warning at all. No cell service, had to use Onstar to be our savior. Thank God they sent a tow truck, although my wife and I with 2 dogs had to wait 4 hours for the tow truck, while semi’s rolled by us going 80 mph. Dealer performed diagnostics on my truck and has to replace the engine due to engine failure. I had the recall completed in September with the new approved oil and cap. I know this is an ongoing problem with GM’s 6.2 engine. Complete engine failure while driving at 75 mph. No engine warning sign. Screen went blank. I will no longer trust this truck or have any confidence in the truck once I get it back. I sure hope GM pays for this. This has caused me endless anxiety.

On Saturday at approximately 5:30 p.m., while driving on a two-lane city street with vehicles around me, my GMC Sierra began malfunctioning. The gauges flickered, warning lights appeared, and a transmission warning activated. As I attempted to safely pull over, the vehicle began stuttering and then completely stalled in the middle of traffic. Cars swerved and honked to avoid hitting me. Fortunately, no collision occurred, but the situation was extremely dangerous and frightening. AAA towed the vehicle to the GMC dealership. When I informed them of the incident, I received a text asking whether an over-the-air update had been performed prior to the stall. I confirmed the vehicle had received an update within the past three months. I was then told there is a bulletin stating that after an over-the-air update, the vehicle may suddenly lose communication with multiple modules and stall. The foreman indicated this was likely the cause and that they were consulting Technical Assistance. I asked when it is considered safe to drive a GMC vehicle following an update, as I was never warned that the vehicle could suddenly lose power and stall without notice. I was told they were investigating further. Yesterday, I was informed that engineering directed them to replace the ECM (Engine Control Module) and the Fuel Pump Control Module, with the ECM expected to arrive next Wednesday. I have not been given a confirmed timeline for completion. This appears to be a serious and known issue within GMC, yet there has been no recall and no warning provided to consumers. I was unknowingly driving a vehicle susceptible to sudden and complete power loss. This failure placed my life, my family, and the safety of others at significant risk.

Driving along a main road at 40-45 MPH and coasting toward a traffic light, the engine stalled out. Traffic light turned green and the vehicle would not accelerate. There were no warnings, check engine lights, or sounds. I could not pull to the shoulder due to traffic and had to pull into a left hand turn lane. The truck would not restart. Electrical systems seemed fine. Engine would turn over but not start on multiple attempts. One attempt finally got it to start but it immediately stalled. I was stuck in a dangerous situation at a busy intersection and no way to move the vehicle. It has been towed to the dealership.

I was driving on an overpass and suddenly loss propulsion in my vehicle. My vehicle stopped all of a sudden and while driving, leaving me stranded in the middle of the roadway blocking traffic. Numerous motorists stopped to give a hand but the vehicle would not switch gears from PARK, to neutral to even give me a hand moving the vehicle out of the roadway to the side/shoulder. Due to this issue, authorities were dispatched to my location to conduct traffic control and subsequently called in aide of a tow truck to safely move my vehicle to a better location. I used OnStar in my vehicle and also spoke with a representative who notated the incident and I was advised that a tow truck would take approximately 90 mins to 2 hours to reach me. In this instance, that was too long of a wait for events going wrong with the vehicle itself and was subsequently transferred from the roadway to a GMC dealership, namely Group 1 South on the Gulf Freeway. They are handling my repairs and have diagnosed that the engine needs to be completely replaced and are in the process of repairs. If any information is needed regarding status or repairs, please contact the dealership directly as I do not have any physical or written information on the status of my vehicle. Attached is the towing receipt.

Engine shut off on the interstate with no warning. Would not re-start. Forced to cross lanes on traffic with no engine power or power steering. Dealer stated it was the "Fuel Pump Control Module." Stated it was a common issue with parts most likely in stock, but it would be at least 6 weeks before they could even look at the vehicle.