GMC Yukon loss of power problems

Filed Nov 2, 2026 · Engine · NC

Has 3600 miles and engine suddenly lost power and had back knocking/squealing noise and check engine light started flashing.

Filed Oct 30, 2026 · Engine · NJ

Engine Failure. While driving on the highway at a speed of approximately 70 mph the engine made a noise and the vehicle lost power. The safety factor is that i was on the highway with trucks and busses in which i had to coast the vehicle to the shoulder of the road and call for police assistance. No warning lamps. Vehicle was towed and inspected by the dealer in which i was informed that the engine bearings had locked up. The vehicle needed a new engine.

Filed Oct 26, 2026 · Engine · AR

As I was driving down the road at 60mph, no dash lights or warnings were present. All of a sudden, my 2021 yukon lost all power and I nearly crashed as I was in heavy, fast paced traffic. I got to the side of the road, and it was at this time the engine light came on. Car died and wouldnt start back up.

Filed Oct 20, 2026 · Engine, Transmission · PA

VEHICLE: 2021 GMC Yukon, 5.3L V8 (L84). VIN: [XXX]. Mileage at failure: approximately 88,000. Component: Engine. INCIDENT DATE: XXX While I was driving on a highway, the engine began to misfire and I heard a ticking noise. The check engine light then began flashing, indicating a severe misfire. I pulled off the highway immediately to a rest area. The vehicle was towed to a GMC dealer. The dealer's diagnosis suspected failed valve lifters, and the repair orders call for a misfire diagnosis with the Bank 1 cylinder head removed, and replacement of the camshaft, lifters, and related parts. This failure caused sudden loss of engine performance at highway speed. The engine began smoking. My family and I were in the vehicle, and we were fortunate there was a safe place to stop. I believe this is a known defect. GM Service Bulletin PIP5776, "Misfire Due to Collapsed Lifter," covers 2021 GMC Yukons with the 5.3L L84 engine. It describes a misfire with a bent pushrod leading to a collapsed lifter or a lifter that comes apart, and it attributes the cause to an internal lifter concern. Many other owners of GM V8 trucks and SUVs have reported the same failure, and a class action over the AFM/DFM lifters has been pending against GM in federal court in [XXX] since 2021. I bought this vehicle new and have maintained it. This is the second time this vehicle has left my family stranded on a highway. In 2024, a separate known issue left us, including three children under [XXX], on the side of a major highway about 7 hours from home. GM repaired that issue. For the current failure, GM has not agreed to cover the repair. It has offered $5,951.39 toward an engine replacement, which would leave me responsible for $13,886.59 plus teardown labor. I am filing this complaint so the federal safety agency is aware of this failure, which can cause sudden loss of power on the highway. GM case number: XXX. Dealer: Fred Beans Buick GMC, [XXX]. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Oct 6, 2026 · Engine · TX

While driving on the highway with my child in the car, the car suddenly began shaking and warning lights to check the power train came on the dash. There was also a loss of power in acceleration. Other error codes (303) also appeared with the check engine light also coming in. Upon checking the code later once home, it indicated there was an issue with the lifters. The car was then towed to the dealership where it was confirmed there are issues with both the lifters and the cam shaft and both need to be replaced.

Filed Sep 23, 2026 · Engine · WA

My vehicle was subject to the GM recall involving the 6.2L L87 engine. The dealer completed the required recall inspection, determined that the engine passed, and performed the prescribed remedy for passing vehicles, which included changing to the specified higher-viscosity oil. After the recall inspection and remedy were completed, the engine subsequently failed. While driving on an interstate at approximately 70 mph, the engine failed without any prior warning lamps, messages, or noticeable symptoms. There was an audible warning tone and the instrument cluster displayed a message instructing me to restart the vehicle. I then noticed that the vehicle was in Neutral and the engine showed no RPMs or response when the accelerator was pressed. Pressing the start button did not restart the engine. When I attempted to select Drive, the vehicle displayed a warning indicating that conditions were not sufficient to change gears. The sudden loss of engine power and propulsion while traveling at approximately 70 mph on an interstate created a significant safety risk to myself, vehicle occupants, and others on the interstate. The vehicle could no longer maintain speed with surrounding highway traffic and had to be navigated to a safe location without engine power. The vehicle was towed to the local GM dealer who diagnosed the vehicle with engine failure, stating the engine was seized and the oil filter was full of shredded metal. The vehicle is currently with the GM dealer waiting a replacement engine. I am reporting this incident because the engine failure occurred despite the vehicle passing GM’s recall inspection and receiving the recommended remedy. This raises concern that the recall inspection and/or remedy may not adequately identify or prevent engine failures. The potential inadequacy of the recall remedy is especially concerning from a safety standpoint.

Filed Sep 21, 2026 · Fuel system · PA

My 2021 GMC Yukon has approximately 36,900 miles. On September 12, 2026, the vehicle was at an authorized GMC dealership and passed a state safety inspection. On September 19, 2026, the check-engine warning light illuminated and I returned to the dealership. The dealer performed diagnostic testing and told me the fuel pump pressure was approximately 400 PSI when it should be approximately 700 PSI. I was told the fuel pump needs to be replaced. The vehicle is currently at the dealership awaiting the replacement part: Fuel pump I was not aware of a fuel-pump failure before the warning light appeared. I am particularly concerned because this failure occurred at only approximately 36,900 miles. GM previously recalled 3,386 2021 GMC Yukons under the federal safety agency Campaign 21V‑739/GM Recall N212332040 for a fuel-pump power-control-module defect that can cause the fuel pump to fail or operate intermittently, interrupt fuel flow and potentially cause the engine to stall. My 2021 Yukon is not included in that recall and currently shows no unrepaired recalls associated with my VIN. I believe this represents a potential safety concern because inadequate fuel delivery or a fuel-system failure while driving could cause reduced engine power or an unexpected stall, increasing the risk of a crash. Given the low mileage, the dealer-confirmed fuel-pressure problem, and the existing fuel-pump-related safety recall affecting other 2021 Yukons, I am concerned that my vehicle may have the same or a related defect despite not being included in the recalled population. I believe the federal safety agency should evaluate whether additional 2021 Yukons should be included in a safety investigation or recall. I am paying out of pocket to have the fuel pump replaced and am filing this complaint to document the failure.A fuel-pump failure at only 36,900 miles is extremely concerning. I ask the federal safety agency to determine whether my vehicle has the same or a related defect and whether the existing recall population should be expanded.

Filed Sep 14, 2026 · Engine, Transmission · AL

On May 8th of 2026 my 2023 GMC Yukon with approximately 42,900 miles experienced an complete failure of the 6.2L engine requiring replacement. The engine failure occurred despite the engine having recently undergone inspection and special oil being used related to the federal safety agency 25V274 / GM N252494000 recall. When the engine failed, the vehicle could not be towed or pushed out of the flow of traffic because the computer will not allow the vehicle to be shifted into neutral, only showing "Conditions not correct for shift" in the instrument cluster. This sudden and unexpected loss of engine power combined with the inability to remove the vehicle from the lane of traffic creates a dangerous situation.

Filed Sep 10, 2026 · Engine · AL

The car lost all engine power on the interstate of I10. Leaving me without power, barely able to get to the side of the road. Warning only when lost engine power on the highway. Cannot be driven.

Filed Sep 6, 2026 · Engine · MN

I am filing this complaint regarding a catastrophic engine failure in my 2023 GMC Yukon Denali. I purchased the vehicle on January 30, 2026. Shortly after purchasing it, the vehicle suffered a catastrophic engine failure. The failure was severe enough that the engine had to be completely replaced. My vehicle was out of service for approximately 38 days as a result. This was not a minor mechanical issue or routine repair. It was a catastrophic failure of a major component in a relatively new vehicle. I am extremely concerned about the safety implications of an engine failing without warning. An unexpected engine failure can result in a sudden loss of power and the inability to safely accelerate or maneuver, particularly when traveling at highway speeds or in traffic. The fact that the engine required complete replacement raises serious concerns regarding the reliability and safety of this engine and whether other GMC and Chevrolet vehicles equipped with the same or related engine may be experiencing similar failures. I am requesting that the federal safety agency formally document this catastrophic engine failure and investigate whether it is part of a broader pattern of engine failures involving these GM vehicles. I have documentation showing the engine failure, dealership diagnosis, complete engine replacement, repair history, and the approximately 38 days the vehicle was out of service. I can provide these records upon request.