2021 Chevrolet Suburban

The Office of Defects Investigation (ODI) has received 36 Vehicle Owner Questionnaires (VOQs) alleging engine failure in vehicles subject to Recall 25V274. In each VOQ, the engine had the recall remedy completed prior to the reported failure incident. Recall 25V-274 addresses vehicles equipped with a L87 6.2L V8 gas engine that experienced engine damage or failure. Recall 25V-274’s remedy includes an engine inspection.  Based on the results of the inspection the vehicle will receive an oil change to a higher viscosity oil or an engine replacement.  The complaints received allege failures of both remedies. ODI is opening this Recall Query (RQ) to assess the adequacy of the remedy for Recall 25V-274. To review the ODI reports cited in the Opening Resume ODI Report Identification Number document, go to NHTSA.gov.

The Office of Defects Investigation (ODI) has received 1,157 reports of engine bearing failure failures in the L87 6.2L engine produced by General Motors (GM). Of the 1,157 reports received, 173 are outside of the scope of recall 25V-274. These engines are installed in Model Years (MY) 2019–2024 Chevrolet Silverado 1500 and GMC Sierra 1500, and 2021-2024MY Chevrolet Suburban and Tahoe, GMC Yukon/Yukon XL, and Cadillac Escalade/Escalade ESV vehicles. The subject engine failures were investigated as part of a Preliminary Evaluation (PE25001).  GM determined that these engine failures were due to multiple supplier manufacturing and quality issues. GM issued recall 25V-274 to address the supplier manufacturing and quality issues produced between March 1, 2021, and May 31, 2024. Based on the issuance of recall 25V-274, NHTSA has closed PE25001. ODI continues to receive a significant number of reports of engine failure in vehicles outside the scope of 25V-274.  This presents a potential safety risk that warrants further investigation.  ODI is opening this Engineering Analysis (EA) to further evaluate the scope and severity of the potential problem and to fully assess the potential safety-related issues of vehicles built outside the recall scope. To review the ODI reports cited in the Opening Resume ODI Report Identification Number document, go to NHTSA.gov.

On January 16, 2025, the Office of Defects Investigation (ODI) opened Preliminary Evaluation PE25001 after receiving complaints and field reports concerning engine failures in MY2019-2024 GM’s full-size truck and SUV T1XX platform equipped with the L87 6.2L V8 engine. These complainants alleged engine bearing failures resulting in knocking and growling noises from the engine’s bottom end and in some cases more severe consequences such as broken connecting rods leading to engine damage, or engine failure. If the engine fails during vehicle operation, the vehicle will lose propulsion, increasing the risk of a crash. On April 24, 2025, GM issued recall 25V-274 to address the concern with L87 engines produced between March 1, 2021, and May 31, 2024.  GM cited the root cause as a supplier manufacturing and quality issues. GM’s  recall remedy will be either an oil change to an oil with a different viscosity or engine replacement depending on the results of the remedy inspection procedure. To date, ODI has received 1,157 allegations of engine bearing failure. GM submitted 55,464 reports in total, with 29,752 unique VINs. ODI continues to receive allegations of L87 engine failures which fall outside of the scope of recall 25V-274. Based on GM’s recall, ODI will close this PE. NHTSA will continue to investigate complaints of engine failure outside the scope of recall 25V-274 as part ofEngineering Analysis (EA25007). To review the ODI reports cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.

On April 9, 2021, the Office of Defects Investigations (ODI) opened PE21-010 to investigate instances of air bag malfunction indicator light (MIL) illumination and potential for frontal air bag non-deployment in several vehicles manufactured by General Motors (GM). The vehicles included model year (MY) 2020 through 2021 CT4 and CT5 passenger cars, Sierra and Silverado trucks (1500/2500/3500 models), XT4 and MY 2021 Escalade, Suburban, Tahoe, Yukon SUVs.Technical Service Bulletin (TSB) 21-NA-005, issued in March 2021, addresses air bag MIL illumination with diagnostic trouble codes (DTCs) B0001-1B or B0012-0D. It cites rust particles in the connection terminal interface of the driver air bag inflator housing as the cause of the air bag MIL illumination. Illumination of the air bag MIL under these circumstances may result in a non-deployment of the frontal driver air bag during a frontal collision and increased risk of injury to the driver.GM stated a correlation exists between production delays due to the pandemic shutdown and premature corrosion initiation on the surface of the air bag inflator housing, which, in some cases, caused rust development during a seven (7) month period of vehicle production. In the rare instance when a rust particle dislodges from the driver air bag inflator housing and enters the air bag connector prior to assembly, an intermittent resistance spike at the air bag connector may result. The condition generates excessive resistance in the air bag electrical system when the steering wheel horn cover is manipulated or the steering wheel is turned. This excessive resistance is momentary. A crash commanding air bag deployment would need to occur exactly when the momentary excessive resistance occurs. Thus, there is a very low likelihood the hazard will present a risk during a crash of sufficient severity to warrant a commanded deployment. This failure mechanism occurs early in life and results in an air bag MIL illumination that corresponds to a DTC warning the driver that the vehicle requires service. The vehicle's air bag remains functional while the MIL is illuminated, and the DTC is present.Once the connection of the driver air bag module to the clockspring is made at the plant, or at the dealership for service, there is no longer an opportunity for rust migration into the connection point. The connector is sealed and has gold terminals, eliminating the expectation of fretting corrosion. All subject vehicles passed standard corrosion validation testing for extensive corrosion with no issue of air bag non-deployment.There is a low rate of occurrence: 1.41 incidents per thousand vehicles (IPTV) for all related occurrences, and 0.04 IPTV for occurrences with a mention of visible rust and/or corrosion on the air bag inflator housing. The average occurrence mileage for the subject vehicles is approximately 2,100. Every occurrence related to the alleged defect experienced an air bag MIL illumination and there are no verified allegations of air bag non-deployment within all data sources.To date, there have been no reported fires, crashes, injuries, or fatalities related to this issue. In view of the low rate, and the nature of early-life failure, the high detectability of failures, and low potential hazard to drivers, this Preliminary Evaluation (PE) is closed. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist. The agency reserves the right to take additional action if warranted by new circumstances.Review the ODI reports cited above at nhtsa.gov under the following identification numbers: 11537927, 11528888, 11525020, 11521401, 11506057, 11493107, 11486767, 11441525, 11433146, 11425658, 11423440, 11385267, 11376429, 11373466, 11366995.

The contact owns a 2021 Chevrolet Suburban. The contact stated that while driving approximately 40 MPH, the vehicle failed to accelerate as needed. The contact was able to coast to the side of the road, and the vehicle was turned off. There were no warning lights illuminated. The vehicle was towed to the dealer and was diagnosed with fuel pump power control module failure. The vehicle was not repaired. The contact discovered a recall for the issue; NHTSA Campaign Number: 21V739000 (Fuel System, Gasoline); however, the VIN was not included. The manufacturer was informed of the failure and confirmed that the VIN was not included in NHTSA Campaign Number: 21V739000 (Fuel System, Gasoline). The manufacturer opened a case for the failure. The failure mileage was approximately 70,000.

NHTSA ID

11755959

Incident

Aug 8, 2026

Mileage

70,000 mi

Fuel pulp module failed on highway. Was told there is not a recall on my VIN even tho online there is a recall and known issue for the part

NHTSA ID

11755546

Incident

Aug 4, 2026

The contact owns a 2021 Chevrolet Suburban used to tow a 30-foot trailer. The contact stated that while towing the trailer and driving 60 MPH up an incline with no shoulder, the vehicle shut off in a remote area. The contact was able to move the vehicle off the roadway. There were no warning lights illuminated. The brakes and power steering features became inoperable. The vehicle shifted to neutral without driver input. The contact stated that the failure was associated with NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling). The local dealer was not contacted. The vehicle was not diagnosed or repaired. A hauling company was contacted to tow the vehicle. The manufacturer was notified of the failure and opened a claim. The failure mileage was approximately 106,000.

NHTSA ID

11753933

Incident

Jul 29, 2026

Mileage

106,000 mi

The contact owns a 2021 Chevrolet Suburban. The contact stated that while driving on the highway, the vehicle experienced reduced engine power and failed to exceed 30 MPH. A message pertaining to the deceleration was displayed. The following Monday, the vehicle failed to exceed 35 MPH, and a friend followed the contact while driving to the dealer. The dealer recommended a fuel filter replacement. The contact declined the repair because the fuel filter life was at 47%; however, the dealer proceeded with the replacement. The contact provided the diagnostic trouble code to an independent mechanic, who informed the contact that the failure was associated with TSB Numbers: 20-NA-197 and 18-NA 361. The contact then advised the dealer of the TSBs, and the dealer determined that the fuel pump module and fuel tank module needed to be replaced. The vehicle was repaired. Additionally, the contact stated that the second-row passenger’s side seat belt buckle failed and was replaced under an extended warranty, although the part was previously replaced under a recall. The manufacturer was notified of the failures several times, but no assistance was provided. The failure mileage was approximately 92,709.

NHTSA ID

11752994

Incident

Jul 11, 2026

Mileage

92,709 mi

Pulled out in 4 lane traffic. Got almost to 55mph. Vehicle lost all power, slowed down and auto shifted to neutral, vehicle stopped and went to park. Vehicle would not start back nor transition to Neutral to remove from highways. 2021 suburban with just 35,000miles. Shut down a lane on a 55mph highway. Code P129F

NHTSA ID

11752904

Incident

Jul 26, 2026

What component or system failed or malfunctioned, and is it available for inspection upon request? (On our 2021 gasoline suburgan, the rear wheels locked up at free-way speeds, which nearly caused a possibly fatal accident. The lock released but it appears the strain caused rear differential gear teeth to break and the rear differential now needs to be replaced for the vehicle to operate properly.) How was your safety or the safety of others put at risk? (The sudden rear wheel lockup at freeway speeds resulted in temporary loss of control of the vehicle and significant surprise to the driver, who, after swerving into the adjacent lane was able to gain control of the steering and stop the vehicle. Had there been another vehicle in the other lane the MVA could have been fatal for 9 people in the suburban and any other vehicle involved.) Has the problem been reproduced or confirmed by a dealer or independent service center? (The rear differential damage was confirmed by a dealer.) Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? (No.) Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? (No warning or messages. This has happened 3 times over 3 years, always on extended trips 9-12 hours in duration. The first two times nearly caused an accident but no differential damage. This third time, the differential was immediately damaged due to the incident. We have since learned that this is an issue with 2022 suburbans, for which a recall has been issued. A recall has also been issued for 2021 DIESEL suburbans. However, no recall has been issued to gasoline 2021 suburbans, but apparently needs to be.)

NHTSA ID

11750547

Incident

Jul 9, 2026

COMPONENT: The 10-speed automatic transmission failed on 6/29/26, locking the vehicle completely in neutral. The neutral override could not be disengaged even by dealership technicians. Vehicle is currently at [XXX] Chevrolet, [XXX] and is available for inspection. SAFETY RISK: I have 3 young children who are regular passengers. The failure occurred without warning. Had it happened at highway speed in oncoming traffic, I would have had no ability to move the car — creating a direct risk of a serious or fatal collision. CONFIRMED BY DEALER: Yes. Don Hewlett Chevrolet received the vehicle on 6/30/26 and confirmed the failure is directly related to two active federal recalls: NHTSA #24V-797 (10-speed transmission valve body failure/wheel lockup) and NHTSA #22V-036 (driveshaft assembly/loss of propulsion). Vehicle has been unrepaired for 13 days with no timeline provided. OTHER INSPECTIONS: Vehicle has been in possession of Don Hewlett Chevrolet since 6/30/26. No manufacturer representative, police, or insurance inspection has occurred. WARNING SIGNS: None. No warning lamps, messages, or symptoms appeared before the failure. The power train locked suddenly and completely without any prior indication on 6/29/26. Despite the dealer confirming this is recall-related, they have indicated I may owe partial repair costs. Under 49 U.S.C. § 30120, GM must remedy recalls at no charge regardless of mileage or warranty. I am requesting NHTSA investigate both the failure and GM's attempt to charge the owner for federally mandated recall repairs. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11750175

Incident

Jun 29, 2026

I had a recall serviced on a Friday which was completed by the dealership. My car sat all weekend and was not driven until Monday AM which was fine. After work, there were several warning lights that popped up and it was making a terrible noise. I was unable to drive home and had to have my car towed to the dealership. Following there inspection, my engine had to be replaced due to a known issue with this engine and GM. Cylinder #2 misfire, lost compression - lifter had spun in guide, camshaft is damaged - engine needs to be replaced. Unfortunately, I was just out of warranty so it was either pay $12,000+ for a new engine or walk away from a car that I love. I just don't understand why if GM knows this is an issue, why there is not some sort of recall on it.

NHTSA ID

11748810

Incident

Feb 2, 2026

This PI provides diagnostic tips for diagnosing electric trailer brakes issues.

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This Preliminary information communicates an issue with an OTA pending message still displayed after an OTA event and how to reset/clear the message.

This PI provides diagnostic tips for diagnosing electric trailer brakes issues.

This Preliminary information communicates to dealer to perform a MEC reset for wireless projection issues

Pi created to provide GM dealers with information on gathering information for projection issue