On [XXX] while traveling on a highway, the vehicle lost drive power-?"the gear selector would not remain in Drive and reverted to Neutral for approximately 10 minutes. This created a serious safety hazard due to sudden loss of propulsion in moving traffic. The event was captured by OnStar, which emailed an automated incident alert. I later received a GM safety recall notice concerning potential engine loss of propulsion for vehicles with the 6.2L L87 engine (NHTSA 25V-274 / GM N252494000/001/002). I presented the vehicle to Ewing Buick GMC (Plano, TX) on July 23, 2025 for recall service and retrieved it on July 28, 2025. Approximately one week later, during an interstate trip to Kansas City, the engine catastrophically failed about one hour from my destination, leaving the vehicle disabled on the roadway shoulder. Roadside assistance towed the truck to Briggs Auto (KS). Briggs Auto diagnosed engine failure and ordered a replacement engine. I was informed the engine is on back-order with no estimated arrival, and the shop is under-staffed, prolonging repairs. The vehicle remains out of service. The sequence-?"pre-recall loss of propulsion, post-recall service, and then engine failure within a week-?"shows a serious safety defect that can lead to sudden loss of power at highway speeds, risking a crash. Frequency: Loss of propulsion occurred at least twice (March highway incident; subsequent engine failure in early August). Warning Lights/Messages: [Gear refuse tom shift to Drive mode.] Injuries/Crashes: None, but risk was substantial due to sudden power loss. Dealer Involvement: Ewing Buick GMC (recall visit); Briggs Auto (diagnosis/engine order). Attachments/Supporting Docs: OnStar email, recall notice, repair orders, tow documentation, photos/video. Please investigate whether 2024 GMC Sierra trucks with the 6.2L L87 engine continue to pose a loss-of-propulsion risk after recall service and whether parts shortages/back-orders are delaying effective remedy INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION

- Farmers Branch, TX, USA

Intermittently there isn't any sound from informational center speakers, this includes not sound of the turn signal indicators working. No sound from any vehicle component, vehicle has the current software release from GM. the only way I've found to get sound again is to leave the vehicle set not running for some period of time, short off then back on doesn't seem to clear the issue. I've check with the dealer and from what I understand this is a known issue with 2024 & 2025 GM informational centers.

- Mead, WA, USA

Subject: Urgent Safety Complaint Dear GMC Customer Service, I hope this message nds you well. I am formally reporting a serious safety issue with my GMC vehicle. The car has experienced multiple dangerous incidents due to likely electrical or software faults, losing power suddenly on two occasions while driving. This is especially concerning given the low mileage of 20,000 km and that the vehicle is still under warranty. Vehicle Information: -?? Model: GMC Sierra SLE, 2024 -?? VIN: [XXX] -?? Current Mileage: 20,000 km Description of the Problem & History: 1. First Incident (At 3,000 km): o The vehicle completely shut down due to an electrical or system software issue while driving. o The vehicle was towed to the dealer and held for over two weeks for repairs. 2. Second Incident (Recently): o The vehicle again lost functionality; the gear was stuck in 1st gear, and I was unable to manually shift. o This occurred while driving, creating another unsafe situation. o The vehicle was again taken to the dealer for repair, and to date, I have not been informed of the root cause. Actions Taken: The vehicle was brought to Sarhan, UAE (Sharjah), Al Ghandi Auto after the rst incident. Despite inspections and repair attempts, the issue has recurred, indicating it was not resolved. And I am prepared to provide photographic or video evidence if necessary. Additional Context: -?? The vehicle is less than one year old and has been regularly serviced on time at authorized centers. The recurring issues strongly indicate an underlying reliability or manufacturing defect. Due to the severity and recurrence of these failures, I refuse any further repair attempts. I formally request either a full refund or a replacement vehicle, as this is unacceptable for a new car. Please acknowledge receipt of this complaint promptly and advise on the next steps for a swift resolution. Sincerely, [XXX] Phone: [XXX] Email: [XXX] Location: Sharjah, UAE INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Detroit, MI, USA

Subject: Urgent Safety Complaint Dear GMC Customer Service, I hope this message finds you well. I am formally reporting a serious safety issue with my GMC vehicle. The car has experienced multiple dangerous incidents due to likely electrical or software faults, losing power suddenly on two occasions while driving. This is especially concerning given the low mileage of 20,000 km and that the vehicle is still under warranty. Vehicle Information: -??Model: GMC Sierra SLE, 2024 -??VIN: [XXX] -??Current Mileage: 20,000 km Description of the Problem & History: 1.First Incident (At 3,000 km): oThe vehicle completely shut down due to an electrical or system software issue while driving. oThe vehicle was towed to the dealer and held for over two weeks for repairs. 2.Second Incident (Recently): oThe vehicle again lost functionality; the gear was stuck in 1st gear, and I was unable to manually shift. oThis occurred while driving, creating another unsafe situation. oThe vehicle was again taken to the dealer for repair, and to date, I have not been informed of the root cause. Actions Taken: The vehicle was brought to Sarhan, UAE (Sharjah), Al Ghandi Auto after the first incident. Despite inspections and repair attempts, the issue has recurred, indicating it was not resolved. And I am prepared to provide photographic or video evidence if necessary. Additional Context: -??The vehicle is less than one year old and has been regularly serviced on time at authorized centers. The recurring issues strongly indicate an underlying reliability or manufacturing defect. Due to the severity and recurrence of these failures, I refuse any further repair attempts. I formally request either a full refund or a replacement vehicle, as this is unacceptable for a new car. Please acknowledge receipt of this complaint promptly and advise on the next steps for a swift resolution. Sincerely, [XXX] Phone: [XXX] Email: [XXX] Location: [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Detroit, MI, USA

The instrument cluster shorted and was blank with no access to any gauges or speedometer. No functionality

- Winter Park, FL, USA

Purchase the truck [XXX]. In January of 2025 it started to feel like the engine was slipping. Near the end of February, it was getting worse and the locks started locking/unlocking on their own. The vehicle stalled two separate times while driving on a main road. The first couple days of March, the car stalled, again on the road while the locks went crazy. Then, on [XXX], after I had pulled out of my driveway in my neighborhood, my car completely shut down. We had to have the truck towed to Coyle GMC, in Clarksville, Indiana. And, as of May 1st, it is still there. We have been told they need some cap for the transmission and they don't know when they will get it. They offered to give us a new transmission, but they don't know when they'll get it. I am making car payments on a car that I have not had since May 7th. Unfortunately, because I drive my car for work, it had it's 32000 miles on it, so I can't turn it in for the lemon law. I'm very lucky that my son and I were not injured when the car stalled in the middle of the road. This is an ongoing issue with GMC, and I think it should be illegal that they were selling these trucks. I have a brand new truck that I haven't driven in 2 months. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Louisville, KY, USA

While exiting the highway and transitioning into a turn lane, my 2024 GMC Sierra AT4 (with 12,887 miles) suddenly and completely shut down without any prior warning. All vehicle systems-?"including electrical-?"failed simultaneously. This included the dashboard, steering assistance, and emergency lights, which significantly compromised my safety. I was unable to alert surrounding drivers or move the vehicle out of the traffic lane. There were multiple cars behind me, and I was placed in an extremely unsafe situation due to the sudden loss of control and inability to signal or restart the vehicle. I immediately contacted emergency services, and a police officer arrived approximately 10 minutes later to assist. Roadside assistance later pulled diagnostic code P0016 from the truck-??s computer. I have since learned that this code corresponds to a known engine timing defect and is the subject of a recent GMC recall issued just days prior to the incident. The failure occurred without any warning lights, messages, or symptoms beforehand. The vehicle is now with a GMC dealer and is available for inspection upon request. To my knowledge, the issue has not yet been independently confirmed, but I believe it is directly connected to the recalled component.

- Sunnvyale, CA, USA

Driving on the highway, moving to pass another vehicle, engine shut off forcing me to coast to the shoulder. No warnings and didn't notice loss of power until I saw that the vehicle had been shifted into neutral. Had 2 kids in the truck and could not get GMC service department on the phone, had to walk up an onramp in order to get my kids home with me in an Uber. This is a 2024 6.2L GMC with only 13,000 miles. Service department took over a week to check initial issues, said it was a fuse block which they replaced. Did not resolve the issue, then it was the starter, which did not resolve the issue, after 2 weeks they told me the engine was locked up due to internal failure and it will be several months before the truck is operable. GM has stated they the issue needs to occur 4 times before a buyback would be considered.

- Anchorage, AK, USA

Truck just made a year old and killed on me in the middle of road. They are saying I need a new engine and maybe transmission. Could not shift truck into neutral, which left me stranded on busy road. For unsafe and had me nervous. Trying to get GMC to buy me out of this vehicle. Had same problem with 6.2 liter prior to this truck. Engine and transmission was replaced. They promised if I bought new truck, I wouldn-??t have the issues and here I am again. This is terrible.

- Denham Springs, LA, USA

The contact-??s son owns a 2024 GMC Sierra 1500. The contact stated that after coming to a complete stop, the -??Service Traction Control-?? message was displayed on the instrument panel. The contact turned off the vehicle and waited for a while before attempting to restart the vehicle; however, the vehicle failed to restart. The contact stated that the -??Service Steering Column-?? message was then displayed on the instrument panel. A dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The failure mileage was 28,140.

- Los Lunas, NM, USA

Intermittent problems with various systems freezing up or not working: Windshield wipers freezing for several seconds mid-wipe. Nearly caused accident. Heads up display not retaining settings Seat controls (bladders that inflate deflate) intermittently working/infotainment screen freeze (where seat control is displayed). Lane departure warning inconsistently working (beeping) Radio quits playing for several seconds and screen goes dark Blinker stops blinking and then re-starts 6.2L engine slow/rough idle continuously hunting for stable speed (This is the only problem that is NOT intermittent). At times almost dies. A/C unit stuck on "hot" delivering 92 degree air when outside 72 degrees. Temp set at Low. (No A/C just trying to get fresh outside air in). Vehicle was under recall and control modules "reflashed" before purchased (new). Dealer reflashed which did not solve problems. Dealer cannot duplicate (but they only spend a little time looking at the issue). Has been in shop off/on for about 2 weeks attempting to resolve. Issues on occasion still occuring since Mid October 2024 purchase.

- Austin, TX, USA

On 2 occasions now my tailgate has opened on its own. The first incident happened sometime after I got home from work for the night, when I went to leave in the AM my tailgate was resting on the garage door and had been scratched. The second time it happened I didn-??t notice it while driving but when I went to close the garage door I looked back and saw the gate was open and partially sticking out of the garage. Nothing happened this time to put anyone at risk however there is damage to the truck and if it happened while hauling something could have come out and hurt someone or damage property. I have not brought it to a service center yet. No warning

- Derry, NH, USA

Truck thinks I-??m about to run into something and slams on its brakes. Last time it sent my sister to the hospital to get 6 staples in her head. Digital cluster goes on and off as well as the infotainment center. Transmission bangs and shifts horribly. 900 miles on the truck with a check engine light and transmission warning.

- Boynton Beach, FL, USA

See attached document for complaint.

- Hartford, CT, USA

I bought this 2024 GMC Sierra new in February of 2024. I have been having several problems. Mainly the back up camera works intermittently. I have had my truck into the dealer 5 times for the same problem. I have contacted GMC to initiate a buy back. I have had the entire infotainment system replaced and am still having problems. My truck goes into the dealer, luther brookdale GMC, again 0ctober 17th, 2024 for the 6th time. I have been dealing with this problem for over eight months I have videos if it would do any good.

- Vadnais Heights, MN, USA

10/9/24: All interior vehicle sounds (turn signals, hazard lights, parking warnings, collision warnings, etc.) along with the audio sound system, are audible in my vehicle via the vehicles-??s audio system speakers. For reasons unknown and without warning, all interior vehicle sounds and the audio sound system cease to make audible sound; however, the infotainment display screen and the instrument cluster screen continue displaying normally and appear to function properly (system still accepts touch screen inputs and visibly displays volume knob input adjustments). So, in summary, a disconnect occurs between the infotainment system / vehicle audible warnings and the vehicle-??s speakers, through which the sounds emitted. We purchased our 2024 GMC Sierra 1500 AT4 as a brand-new purchase on 9/30/24 and it is completely stock, with no post-purchase or aftermarket alterations having been made to the vehicle. This issue has occurred on two separate occasions since the purchase date, with the occurrences happening on 10/8/24, and once on 10/9/24. When this sound-disconnect issue occurs, it will last indefinitely until we remedy the issue. The only remedy for this issue that has worked thus far requires that we completely shut the vehicle down, wait a few minutes, and then restart the vehicle. In researching this issue, I have found multiple comments over various forums by various users who have reported dealing with this same issue.

- Rancho Mission Viejo, CA, USA

Stereo volume went to max, startled me while driving through residential neighborhood. Then muted itself and wouldn-??t work. Stereo reset itself and then played at normal volume but none of the controls worked until I restarted my truck. Bought it brand new last week

- Wailuku, HI, USA

Backup camera fails to perform in poor lighting. Camera images are distorted appearing as a mix of colors The lack of clarity, renders the rear view camera as worthless.

- Plymouth, MI, USA

The DIC randomly displays -??check trailer wiring-?? then says -??brakes connected-?? over and over. When this happens the brakes on the trailer quit working, all lights continue to work all the time. It hasn-??t been back to the dealer yet but I will take it when I can. Other vehicles have no issues with this trailers brakes when towing. I have replaced the trailer pig tail 7 pin plug, cleaned all connections etc. The only thing that works so far is to disconnect one of 4 electric brakes then the DIC is silent and 3 brakes function. I even replaced some magnets in the trailer brakes but they were working prior to the DIC message that began on my second towing trip. There is a technical bulletin for some GMC trucks but my model isn-??t listed as one. I believe it to be the controller or software since nothing seems to work as far as the trailer is concerned. It isn-??t my trailers issue-??I know they are going to say it is.

- Valdez, AK, USA

Backup lights are very dark making it very hard to see at night while reversing to the point where they are unsafe. Cannot see at all in rainy conditions.

- Columbia , TN, USA