2021 GMC Yukon: engine knocking or ticking

Filed Oct 23, 2026 · Engine · MS

crank/rod failure on 6.2 engine. yes it is available same as other people with blown 6.2s yes, GMC dealer diagnosed crank failure no no. engine still runs but is knocking and squealing but dies after a few mins and won't restart till it cools off

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 13, 2026 · Engine · NY

In late February / early March 2026, at approximately 139,000 miles, my 2021 GMC Yukon Denali with the 6.2L V8 (L87) engine developed a loud knocking/rattling noise that sounded like a loose part inside the engine. The vehicle kept running, but the noise persisted. I took the vehicle to a GMC dealer. The dealer checked the VIN and told me there was no recall covering my vehicle. The engine was found to have internal damage consistent with connecting rod / bearing failure. A replacement engine was quoted at approximately $8,000. Because I could not afford that, an independent mechanic in Connecticut rebuilt the engine for approximately $5,500 in total (about $4,500 in parts plus $1,000 in labor), paid out of my own pocket. I have all the invoices for the repair. This failure appears to be the same connecting rod and crankshaft bearing defect covered by Recall 25V‑274 for other 2021–2024 vehicles with the 6.2L L87 engine, but my VIN is excluded from that recall according to the dealer and the federal safety agency/GM VIN lookups. No crash and no injuries occurred. I am reporting this failure so it is documented in the federal safety agency's investigation of L87 engines outside the recall population, and I respectfully request a review of why this VIN was excluded and whether reimbursement for the repair is possible if coverage is expanded.

Filed Sep 8, 2026 · Engine · MI

My 2021 Yukon Denali received the Recall 25V‑274 oil fix and I am now experiencing an active light engine knock. My gas mileage has reduced significantly and I am having to add oil in between regular oil changes. Not only does it burn through oil and fuel faster but I now get charged an extra fee for "Premium oil". My oil changes cost me roughly $40 dollars more now. ($140 instead of $100) I don't feel as if this fix with the oil change has improved anything and that the cost to maintain the vehicle has only gone up. I am still worried this vehicle will break down on my next road trip.

Filed Sep 3, 2026 · Engine · MS

My 2021 GMC Yukon began experiencing severe engine problems, including shaking/rough running, a noticeable ticking/knocking noise from the engine, and a flashing check-engine light. The vehicle also displayed Service ESC and traction control warnings and exhibited symptoms of an engine misfire. I took the vehicle to a dealership for evaluation. I was advised that the problem may involve failed lifters and that the vehicle could be out of service for several weeks for repairs. I was also advised that the repair could be very costly. At this time, I have not been given a final diagnosis, so the exact internal engine component responsible for the failure is UNKNOWN. I am concerned that the condition presents a safety risk because the engine is running extremely rough and the check-engine light is flashing. I am afraid the engine could lose power or fail while the vehicle is being driven, potentially putting me, my passengers, and other motorists at risk. I have also become aware of the federal safety agency's investigation involving failures of the 6.2-liter L87 V8 engine in GM vehicles, including the GMC Yukon, as well as reports of engine failures occurring after certain repairs or recall remedies. This has increased my concern about whether repairing or replacing individual engine components will permanently resolve the problem. I am submitting this complaint so that my vehicle's symptoms, dealer evaluation, and potential engine failure are documented. The vehicle and affected components are available for inspection upon request. The dealership has evaluated the vehicle, but a final determination of the exact cause has not yet been provided.

Filed Sep 1, 2026 · Engine · TX

My 2021 GMC Yukon Denali with approximately 88,000 miles developed a significant engine knocking noise and was towed to a GMC dealership for diagnosis. The dealership confirmed diagnostic trouble code P0301 (engine misfire) and documented a “knocking noise in lower end at piston rod crankshaft area.” The dealership advised that my vehicle is not currently included in the existing GM recall for certain 6.2L L87 engines. The vehicle has the 6.2L L87 V8 engine. I am concerned because the documented knocking is located in the lower engine area involving the piston/connecting rod/crankshaft area, which is consistent with the type of internal engine failure associated with the L87 engine investigation and recall. I am concerned about the possibility of sudden engine failure and loss of propulsion while driving. I am requesting that the federal safety agency investigate this failure and consider whether vehicles outside the current recall population should also be included. I also recently experienced an engine replacement on another 2024 GMC vehicle. I am providing that information as additional customer experience, but I am not claiming that the two failures are necessarily caused by the same defect.

Filed Aug 31, 2026 · Engine · TX

Engine making a loud ticking noise. Lifters broke in the engine. No warnings, no lights. I turned on the vehicle and it started making the noises. Dealer wanted to do an engine swap. Independent service center is changing out the lifters.

Filed Aug 29, 2026 · Engine · NC

I’m currently on my third motor as a result of the L87 engine loss. When I bought the vehicle, I was not aware that the engine had already been replaced however, due to hearing a tick, I brought my vehicle to the dealership for the recall and was told that this is not the original engine, but they had the paperwork for this engine as well. Nonetheless, the engine “passed” their inspection. They changed my oil and replaced my cap. Within six months, I threw a Rod. Not only did I have a horrible experience with the dealership, my new motor is also ticking.

Filed Aug 27, 2026 · Engine · WI

My vehicle is making a knocking sound and has the L87 6.2 V8 engine that is under recall for catastrophic failure. It has been evaluated by 2 mechanics that say it needs a new engine. Yes it is available for inspection upon request. Although it has not shutdown yet, both mechanics have said it is eventually going to be a catastrophic failure. My safety and families safety is at risk of it shuts down and causes an accident. There is no warning light currently displayed.

Filed Aug 22, 2026 · Engine · KS

I am filing this complaint regarding repeated catastrophic engine failures in my 2021 GMC Yukon Denali equipped with the 6.2L L87 V8. I purchased this vehicle as a GM Certified Pre-Owned vehicle. At approximately 7,000 miles, the engine developed a knocking noise and was determined to require complete replacement. I brought the vehicle to the dealership on May 19, 2025, and it remained there until September 17, 2025—nearly four months—while the replacement engine was obtained and installed. Since receiving the replacement engine, I have driven approximately 6,000 miles. On August 4, 2026, I was informed by the dealership that the replacement engine has also failed and requires another complete engine replacement. This means my vehicle has now experienced two major engine failures at extremely low mileage, including failure of the replacement engine. I understand that the 6.2L L87 engine has been subject to a GM recall involving potential engine failure and loss of propulsion. I have now learned that the federal safety agency has escalated its investigation into continued failures involving these engines, including failures occurring after the recall remedy. My experience appears directly relevant to that investigation. I regularly transport my children in this vehicle and am extremely concerned about the possibility of an engine failure occurring while traveling at highway speeds or with my family in the vehicle. I feel fortunate that the previous failures did not occur under those circumstances. I have contacted GM and requested that they repurchase or replace my vehicle. GM denied my request and has refused to provide me with a reason for the denial. I am asking the federal safety agency to document my complaint and investigate whether the existing recall remedy is adequately addressing the underlying safety defect, particularly given that my replacement engine failed after only approximately 6,000 miles.I can provide repair orders, recall documentation, mileage records, and correspondence with GMC

Filed Jul 25, 2026 · Engine · AR

Knocking sound and flashing engine light came on. When brought to dealership it was determined that lower bearing failure took place requiring full engine replacement. '

Filed Jun 5, 2026 · Engine · OK

I am filing a complaint regarding my 2021 GMC Yukon due to a serious engine failure involving the camshaft, lifters, and crankshaft. The vehicle began exhibiting engine ticking and knocking noises, rough idle, loss of power, and reduced performance. These symptoms progressively worsened and ultimately resulted in major engine damage. The vehicle was diagnosed with failed lifters and camshaft damage, which required extensive repairs. In addition, the crankshaft failed, resulting in catastrophic engine damage and making the vehicle unsafe to operate. These are critical engine components that should not fail prematurely under normal driving and maintenance conditions. The most serious concern is safety. The engine's loss of power and deteriorating performance created the risk of sudden failure while driving. A vehicle that loses power in traffic, while merging, crossing intersections, or traveling at highway speeds can create a dangerous situation and increase the risk of a crash. Occupants and other motorists could be placed at risk if the engine fails without warning. My vehicle has been properly maintained and serviced. Despite regular maintenance, these major engine components failed unexpectedly. I am aware that other owners of GMC and Chevrolet vehicles equipped with similar engines have reported comparable camshaft and lifter failures, suggesting a potential defect rather than an isolated incident. The failure resulted in significant repair costs, loss of vehicle use, and concerns about the long-term reliability and safety of the vehicle. I believe these engine failures may indicate a manufacturing or design defect affecting 2021 GMC Yukon vehicles. I respectfully request that the federal safety agency investigate camshaft, lifter, and crankshaft failures in the 2021 GMC Yukon and determine whether a safety-related defect exists that warrants corrective action or a recall.