2023 GMC Sierra 1500: sudden loss of power

Filed Nov 2, 2026 · Engine · CO

Information related to GMC 25V274 recall for 2023 GMC Sierra 1500 6.2L. Recall oil change inspection and change of oil to higher viscosity performed summer of 2025 (prior to my ownership). On May 17, 2026 the Truck lost engine power without warning and would not start again. Fortunately I was on a road and location where I could coast into a parking lot, but again the vehicle provided no advanced warning of any issue. Towed truck to dealership and determined that exact engine problem noted in recall had indeed occurred to engine. So GMC recall efforts to inspect and change oil had NO effect on the engine defect. Engine was replaced.

Filed Oct 29, 2026 · Fuel system · WA

On [XXX], at around [XXX] my 2023 GMC Sierra 1500 Elevation suddenly lost power while I was driving eastbound on [XXX]. The battery was still running, but the engine lost power and the accelerator did not respond and the truck would not move. I was stranded in the roadway. OnStar emailed me about a critical vehicle issue and reported DTC P129F. Because the truck was stopped in a live lane of traffic, I called 911. Responders blocked part of the road to protect me and to give the tow truck room to recover the vehicle. No one was injured, but this could easily have caused a serious collision. A few days later, I had the truck towed to Seaview GMC in Lynnwood, WA. The dealer diagnosed an internal failure of the fuel pump power control module, the K111 Fuel Pump Driver Control Module mentioned in the GM Bulletin earlier this year. This matches a known issue described in GM Service Bulletin 24-NA-139, which covers DTCs P129F and P023F and lists 2023 Sierra 1500 models. The bulletin describes symptoms including no-start and stalling. The dealership has attempted to charge me $200 for diagnosis and $261 for the fuel pump module. I had asked them if this was covered under warranty, they responded that they would check with their warranty specialist. This conversation happened at the Seaview GMC Dealer approximately 5pm on [XXX]. The informed me they would call the next day to confirm if this is covered or not covered by warranty. I am reporting this because a sudden loss of power while driving on a highway is a serious safety risk. I am concerned that other owners may experience the same failure at highway speed, and I would like the federal safety agency to review this issue. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Oct 20, 2026 · Engine · 50,000 miles · TX

The contact owns a 2023 GMC Sierra 1500. While driving at 30 MPH, the vehicle jerked and lost motive power. The vehicle was restarted and driven at reduced power to the dealer, where unknown electrical repairs were performed. The failure persisted, and the vehicle was towed to a second dealer, Grissom Chevrolet (181 S Interstate 20 Frontage Rd, Pecos, TX 79772), who replaced the engine. However, the failure recurred, and the vehicle was towed back to the first dealer, who diagnosed that the spark plugs and other unknown parts needed to be replaced. After the dealer performed the unknown repairs, the check engine warning light illuminated when the contact's son-in-law picked up the vehicle. The contact's brother, an independent mechanic, diagnosed that the catalytic converter and other unknown parts needed to be repaired. The contact filed a lemon law claim. The manufacturer was notified of the failure by phone. The failure mileage was approximately 50,000.

Filed Oct 16, 2026 · Engine · MI

A 6.2 engine operated as expected for 75,000 miles. I turned a corner at an intersection, and had a loud knocking in the engine occur. For the first 75,000 miles, there wasn't any unusual engine noises or oil consumption.Seconds later the engine light illuminated on the dash, reduced engine power, and every safety light within the dash was going on and off. I managed to drive slow and return to my residence and have the truck towed to the dealership to have the engine replaced. As many have learned, the recall from GM states to either pass a PICO test and change to 0W-40, or have the engine replaced if necessary. My concern is that the replacement engine is the exact same engine with the exact same components that assuredly will fail due improper design, production, and overlooked components that attribute to such failure. The crankshafts are being found to have values of "peaks and troughs" within the finish that are many times out of given specifications. The extraneous pressures created by the Dynamic Fuel management system over time are creating stresses and friction that the designated oil and oil pump are not compensating for. These mechanical stresses over different durations, seem to be part of the cause of the engines failure. The replacement engine came with a warranty that only extends to an odometer reading of 150,000 miles. I no longer have confidence in a manufacturer that is enforcing false resolve upon a customer as a solution. The new engines of replacement have been failing as well. This result exhibits a fact that shouldn't be ignored. The new engines have the same components and are due to fail, just the same as the original. I would like the manufacturer to resolve this failure by offering a "true" solution. A proven remedy and a documented warranty that assures the manufacturer stands behind the product. GM sells a new product that fails and then recalls the engines to replace with the same failed components and lack of warranty.

Filed Sep 28, 2026 · Engine · OH

6.2L engine lost power and failed at highway speed with no warning lamp or prior indication of failure. Engine recall/Pico test and oil viscosity change performed by dealer at 40,000 miles. Engine failed at 45,868 miles.

Filed Sep 23, 2026 · Electrical, Steering · 83,000 miles · IL

The contact owns a 2023 GMC Sierra 1500. The contact stated that while driving 35 MPH, the vehicle lost power steering functionality. The "Service Power Steering" message was displayed and ESP warning light was illuminated. The dealer was contacted and diagnosed the vehicle with a short circuit in the module used to control the rack-and-pinion system, which had blown the fuse. The manufacturer was contacted by phone and made aware of the failure. The failure mileage was approximately 83,000.

Filed Sep 10, 2026 · Acceleration, Transmission · CO

Purchased above listed vehicle new in XXX. Immediately noticed a 'coolant' smell in cab. brought vehicle in for coolant smell issue on XXX and XXX. We were told that there was no issue until finally on XXX we were told the radiator needed to be replaced at OUR expense. XXX we received a letter from GMC advising the "engine coolant control valve" may fail. In XXX while driving on mountain roads (we live in [XXX]) the check engine light came on and while at 50 mph, the vehicle went into "limp mode" we lost power and speed was immediately reduced. We now know that a symptom of that valve failure is coolant smell in the cab of the car, a problem we had attempted to address with GMC from the beginning. We could have had a serious accident driving on a busy mountain road when this failure occurred. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Sep 1, 2026 · Engine · TX

While driving, my 2023 GMC Sierra with the L87 6.2L engine experienced a sudden, complete, catastrophic loss of engine power. There were no warning lights or messages prior to the failure. This was a one-time event, but it left the truck inoperable and I have been without the vehicle since it happened. The vehicle had recently passed applicable recall checks and had a routine oil change performed, so it was properly maintained leading up to the failure. A sudden loss of engine power while driving poses a serious safety risk, including the possibility of a collision if it happens in traffic or at highway speed. It is unknown whether a dealer has confirmed the root cause, as the vehicle has been out of service since the incident.

Filed Sep 1, 2026 · Engine, Fuel system · CA

I am reaching out to the federal safety agency due to a vehicle that I believe will get me and/or my family in a major accident and cause serious injury or death. The vehicle that I had purchased in 07/08/2025 had a clean history report and was bought at 54,587 miles. It started having issues 8,563 miles later (odometer reading 63,150 ) on a trip that was 400 miles round trip. I was driving the vehicle on a highway at 65 mph and i felt a knocking vibration in the pedal it was not long before i could even pull over when the engine throttle had completely lost power causing the vehicle to almost come to a complete stop immediately having to steer onto the shoulder. after failing with no check engine light or warning present during the use of the vehicle on the road. it was giving off high temp/engine overheating with the engine making a continuous knocking sound in the engine. It eventually seized to work completely not being able to shift into neutral to push, and had to get it towed to the dealership 204 miles away. GM had advised the dealership to replace the whole engine which they did, and that second engine had given out 678 miles later (odometer reading 63,828.) I am now on my THIRD engine and i cannot trust or rely this vehicle for saftey or transporation. i have reached out to GM to file a claim and attempt to adress this issue to try and come to a resolution, however they denied my claim and have said that i am not "eligible" for a buyback program. I am considering getting legal attorney this is very frustrating to say the least GM is a terrible manufacturer for this issue

Filed Aug 29, 2026 · Electrical, Engine · TX

1 - The Engine or something electrical, possibly the ECM, failed or malfunctioned, and yes, it is available for inspection. 2 - The vehicle lost power, reduced speed, was hard to steer, and I couldn't put the hazard lights on; this occurred twice while driving on the highway, once I was driving at approx 75 mph. The results could have been catastrophic not only to myself but to others on the road. These two events are not the only times the truck did this. 3 - No. 4 - No. I filed a claim with GM, but it has been approximately a month, and I've received no updates. 5 - No. Further: This event has occurred 6 times. I've taken it to the dealership three. They cannot duplicate the issue, so no repairs have been done. Apparently, approximately 100 codes come up, but they cannot diagnose the problem.

Filed Aug 9, 2026 · Brakes, Electrical · OH

My 2023 GNC Sierra 1500 has experienced a recurring electrical and safety-related malfunction on multiple occasions while driving. The dashboard and warning lights intermittently flash on, and off and numerous warning messages appear simultaneously. During previous occurrences, warnings included power steering service, safety restraint system, check engine and transmission related messages, including a message instructing me to pull over and shut the vehicle off. During one occurrence, the electric power steering assist stopped working while I was driving. The vehicle was taken to an authorized GMC dealership multiple times while under the factory warranty. The dealer replaced the Brake System Control Module and performed vehicle-wide software/programming updates. When the problem continued, the dealer contacted GM Technical Assistance. The Dealer subsequently diagnosed an intermittent open circuit involving the electric power steering rack-and-pinion/steering gear assembly and replaced the complete steering gear assembly. Despite these repairs, the malfunction has occurred again, during another occurrence while driving on the freeway, the dashboard flashed on and off and multiple warning lights and messages repeatedly appeared, similar to the condition that occurred before the steering gear was replaced. The vehicle currently has approximately 55,000 miles. The condition remains intermittent despite multiple repair attempts. I am concerned that this recuring electrical or vehicle communication failure could again cause loss of power steering assistance or affect other safety-related vehicle systems while driving.

Filed Aug 7, 2026 · Engine, Fuel system · CA

- vehicle started misfiring, ECM, valve timing code, throttle system code, data system, gateway, module,. Vehicle is available and currently at the GMC dealership for continued diagnostic. -this happened on the freeway and out of nowhere the vehicle started shaking, rough, losing power and acceleration, I had to cut someone off on the freeway just to get over to the right shoulder and turned off the vehicle called a tow truck and haven’t been able to use the vehicle since. Vehicle is unable to be driven due to safety issues of increased acceleration and loss of power, intense shaking. -the vehicle is at the dealership now, prior there was a diagnostic performed by a different dealer, and it has been confirmed. -the vehicle is at the GMC dealership now. -ECM check engine light came on prior to the vehicle misfiring and other codes coming up.