2021 Chevrolet Tahoe Engine Problems

While at a drive thru, my 2021 Chevy Tahoe High Country experienced a total failure with no advance warning where the engine shut down and would not restart despite what appeared to be good electrical power. We tried to jump start the vehicle with both another vehicle as well as a AAA power pack with no luck. The vehicle was not movable and had to be towed using a lift truck to the dealer. The dealer performed an analysis, reproduced the problem, and determined that the engine failed due to a spun bearing despite no documented codes from the analysis. In performing research, this failure appears identical to NHTSA Campaign 25V274 / GM number N252494000 however the car has been deemed to not be covered with mileage at 139,300.

NHTSA ID

11754638

Incident

Jul 23, 2026

The engine in my 2021 Chevrolet Tahoe High Country equipped with the 6.2L V8 (L87) experienced a catastrophic failure. While driving, the vehicle suddenly lost power, displayed a “Service ESC” warning, illuminated the check engine light, and unexpectedly shifted into Neutral. After stopping the vehicle, it would not restart. The dashboard would illuminate, but the engine would only produce a faint clicking sound and would not crank. The vehicle was towed to a Chevrolet dealership, where it remains available for inspection. How was your safety or the safety of others put at risk? This failure occurred while I was driving, causing an unexpected loss of power and propulsion. The vehicle became disabled without warning, creating a significant risk of being struck by surrounding traffic. Losing the ability to accelerate or safely maneuver a full-size SUV in traffic placed both me and other motorists at risk of a serious crash. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes. The vehicle was towed to an authorized Chevrolet dealership, Crews Chevrolet. The dealership confirmed that the engine had catastrophically failed and advised that it qualified for replacement under General Motors’ special coverage program for the 6.2L L87 engine. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Yes. The vehicle has been inspected by an authorized Chevrolet dealership. General Motors has authorized replacement of the engine under its special coverage program. No police report was filed because there was no collision.

NHTSA ID

11752953

Incident

Jul 20, 2026

DATE: 06/17/2026 The engine shuts off without warning while I am driving, recurring roughly every 10 miles. When it stalls, the dashboard and electrical accessories stay on, but the vehicle loses motive power, along with power steering assist and power brake assist, which is extremely dangerous at road speed and in traffic. This began immediately after dealer service completed on 6/18/2026. During that visit the dealer performed two safety recalls (N252494000, the "L87 Engine Loss of Propulsion" PicoScope inspection with oil change; and N252510321, ECM software reprogramming) and a valve lifter replacement that required removing both cylinder heads. The vehicle was running and fully drivable when I dropped it off, and was returned stalling repeatedly while driving. It never did this before the service. At first the engine would not restart after stalling. The dealer replaced the starter; it now restarts but continues to stall every ~10 miles. A dealer diagnostic scan recorded numerous "Lost Communication" codes across nearly all control modules, plus control-module input-power codes showing low voltage and power-circuit correlation faults (e.g., U3505, U3018, U3007) and an active loss-of-communication code for the power steering module — consistent with an intermittent loss of electrical power or ground affecting engine control. The engine passed the recall's connecting-rod/crankshaft (PicoScope) inspection, so this is not the recalled bearing failure mode. The vehicle is currently at the dealership and is undrivable. The dealer has ordered a new engine and apparently also a new radiator for reasons unknown. No crash or injury has occurred to date, but the vehicle lost power while on the freeway at speed multiple times. A GM customer assistance case is open. Repair orders and the diagnostic scan are available on request.

NHTSA ID

11747941

Incident

Jun 18, 2026

After a car wash, the car started to smoke out of a tail pipe, down shifting hard, car was shaking while running in park in the driveway- so we took it right to Chevy Turnersville, and they are now saying the whole engine is internally damaged ( not by the carwash) and the whole engine needs to be replaced. The trucks warranty just expired in Feb, the car ran perfectly fine before this. I dont understand how an engine just stops working this fast and out of no where. We took very good care of this truck. Oil changes every time we needed, new tires, new alignment, the mile recommendations, everything! and this happens out of no where. It will now cost $12,000 to repair this which we do not have. Please help and explain this

NHTSA ID

11747386

Incident

Jun 26, 2026

The engine's Dynamic Fuel Management (DFM) lifter failed and damaged the camshaft at around 70,700 miles. The broken components are available for inspection upon request. This failure put occupants at risk because the vehicle suddenly lost power, began shaking violently, and could not accelerate safely in traffic. This unexpected loss of propulsion created an immediate collision hazard. The problem was officially diagnosed and confirmed by a repair service center. It has not been inspected by police or insurance representatives. There were no advance warning signs. At the exact moment of the failure, the check engine light started flashing, the car began shaking heavily, and the engine made a loud knocking sound.

NHTSA ID

11747364

Incident

Jun 15, 2026

2021 Chevy Tahoe with 6.2 engine (VIN: [XXX]) has been experiencing severe oil consumption, and making odd noises during operation. All while NOTshowing ANY recalls for the issue. Although there's an active recall/investigation into the 6.2 L87 engine, which my vehicle has. I've been having Valvoline document the severe oil consumption during oil changes per manufacturer specs. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11746967

Incident

Jun 25, 2026

We have a 2021 Chevy. Tahoe, and we just had an inspection done because a light kept coming on saying that our engine might fail. The shop initially said it needed cam shaft replacement, but now are saying the entire engine needs to be replaced. The care has ~ 67,000 miles on it and is 5 years old.

NHTSA ID

11746218

Incident

Apr 10, 2026

The contact's husband owns a 2021 Chevrolet Tahoe. The contact stated that while her husband was driving at an undisclosed speed, the vehicle shuddered and experienced a loss of drive power. A message to turn on the vehicle was displayed. The contact's husband coasted the vehicle to the side of the road and attempted to jumpstart the vehicle, but the vehicle failed to restart. The vehicle was towed to the dealer, who determined that the engine had seized and the crankshaft had failed. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The contact related the failure to NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the VIN was not included in the recall. The manufacturer was made aware of the failure and advised the contact to file a complaint with the NHTSA Hotline. The failure mileage was approximately 130,000.

NHTSA ID

11743739

Incident

Jun 3, 2026

Mileage

130,000 mi

While driving my 2021 Chevrolet Tahoe, the check engine light illuminated. Shortly thereafter, the engine began shaking severely and I heard clicking and popping noises from the engine compartment. The following morning, the vehicle was barely operable, shaking excessively and unable to properly reverse. Due to the unsafe condition, I had the vehicle towed to the dealership. The dealership diagnosed a failure involving all 8 lifters on one side (bank) of the engine, requiring extensive engine repairs. My vehicle has approximately 74,000 miles, which I believe is low mileage for such a significant internal engine failure. The symptoms included severe engine vibration, misfiring, loss of performance, and the potential for loss of power while driving. This is not the first major failure I have experienced with this vehicle. In approximately April 2023, when the vehicle had about 32,000 miles, it unexpectedly shut off while I was reversing in a roadway. The dealership diagnosed a failed fuel pump control module (fuel pump modulator). Similar failures were later identified in recalls and corrective actions affecting other GM vehicles. I am concerned that my vehicle has experienced multiple failures involving components that appear to be associated with known issues affecting GM vehicles, yet my Tahoe was not included in applicable recalls. These failures created significant safety concerns, including unexpected engine shutdown, loss of vehicle operation, and potential loss of power while driving. I respectfully request that NHTSA investigate whether my 2021 Chevrolet Tahoe vehicles should have been included in existing and future safety recalls related to these defects and other known defects that GM vehicles are experiencing with the motor, transmission and other parts. Note: No invoice is available yet as I am seeking GM assistance due to no warranty status. Estimated repair cost from dealership is up to $8,900.

NHTSA ID

11743348

Incident

Jun 7, 2026

My wife was stopped at a stop light traveling west from and appointment. When the light turned green she moved her foot from the brake to gas when all of the warning lights. It happened at the worst time possible during rush hour and we were fortunate that she was not hit by traffic. After the police arrived to help re direct traffic and wait for a tow truck, we found coolant spilling underneath the engine towards the rear of it. Towed to local repair shop, they inspected and found the engine had a catastrophic failure. Likely related to the current recall for the 6.2l V8 engine installed in this Tahoe.

NHTSA ID

11740788

Incident

May 28, 2026

On May 2nd 2026 I was driving my 2021 Tahoe high country with the 6.2 motor at 60 mph and started to slow down before my left hand turn. In the process of slowing down at about 40mph I heard a loud bang/thud noise. The car had completely shut down all motor related usage. I coasted into the shoulder on the side of the road the vehicle would not restart. I had my children and wife in the car. There were no check engine lights or any other warning signs on the dash prior to this happening. The Tahoe was running perfectly fine. Ended up needing the vehicle towed to the chevrolet dealership. It was confirmed upon dealership inspection by the mechanic that an intake valve spring broke and locked up the engine. We currently are being denied coverage through our extended warranty with endurance to replace the engine.

NHTSA ID

11737454

Incident

May 2, 2026

The contact owns a 2021 Chevrolet Tahoe. The contact stated while driving at an undisclosed speed, the contact stated that several warning lights illuminated. The vehicle was towed to the dealer where it was diagnosed with a failed engine, lane departure modular and the brake master cylinder. The contact was informed that the engine, lane departure modular and the brake master cylinder needed to be replaced. The vehicle was not repaired. The contact was informed that the lane departure module was in back order. The manufacturer was made aware of the failure and a case was filed. The contact was advised to contact the NHTSA Hotline and report the failure. The failure mileage was approximately 78,026.

NHTSA ID

11737018

Incident

Jan 31, 2026

Mileage

78,026 mi

Engine has developed a miss and has check engine code P0300 random misfires. There are subcodes pending of P0011 and P0016 indicating Crank and Cam misalignment. This has all the classic signs for a failing engine. I am taking this truck in for the GM Picoscope test, the oil was changed to 0w40 mobile one supercar oil approx. 2,800 miles ago when the truck was under Powertrain warranty. I will preform a Blackstone oil test to determine if there is abnormal engine wear. My truck is not in the vin. recall range.

NHTSA ID

11736994

Incident

Apr 15, 2026

Check engine light illuminated on my 2021 Chevrolet Tahoe. Upon diagnostic scan, the following emissions-related fault codes were present: P11D5 (NOx sensor), P14D9 (NOx sensor), P2383 (EGR pressure sensor), and P2C7A (NOx catalytic converter efficiency). All components are available for inspection upon request. The vehicle was taken to an authorized Chevrolet dealership for diagnosis. The dealer acknowledged the emissions codes but stated that unrelated components would need to be repaired at owner expense before the emissions system would be addressed, despite these codes falling within the federally mandated 8-year/80,000-mile emissions warranty. The fault codes were confirmed by the dealership. No safety incident has occurred to date, however degraded NOx and EGR function can result in increased harmful emissions output and potential engine performance issues. Warning lamps appeared without prior incident or symptom. The manufacturer has not offered to cover the emissions components under the federal emissions warranty without the owner first paying for additional repairs that may or may not be causally related to the emissions system failure. When the dealer was directly asked, "Are you saying the emissions system itself is functioning correctly, and something else caused these codes to appear?" — the dealer did not provide an answer. This question was asked in order to clarify whether the emissions components themselves are degraded or failed, which would confirm warranty coverage eligibility. The dealer's failure to answer this question directly is noted as part of this complaint.

NHTSA ID

11734900

Incident

Apr 30, 2026

The contact owns a 2021 Chevrolet Tahoe. The contact stated that while driving 65 MPH, there was an abnormal vibration coming from the engine compartment and felt in the steering wheel. The check oil warning light illuminated. The vehicle was taken to the residence and then to the dealer, where it was determined that the vehicle was functioning properly, and there was no oil leak; however, the oil level was low even though an oil change was not yet due. The dealer added oil to the vehicle, and an oil consumption test was ordered. The manufacturer was notified of the failure and a complaint was filed. The vehicle was not repaired. The failure mileage was approximately 48,000.

NHTSA ID

11734758

Incident

Feb 15, 2026

Mileage

48,000 mi

Urgent: Engine Failure Following Recent Service – 2021 Chevrolet Tahoe To Whom It May Concern, I am writing to formally request assistance and an investigation regarding a serious engine failure involving my 2021 Chevrolet Tahoe. In July 2025, I paid out of pocket to have the lifters and camshaft replaced on this vehicle. More recently, while traveling, the vehicle broke down and was taken to Uebelhor Chevrolet, where the valve body in the transmission was replaced. After picking the vehicle up from Uebelhor Chevrolet, the vehicle broke down again approximately one hour later while in Henderson, Kentucky. At that time, the engine began smoking, running rough, and misfiring. I checked the oil level during the incident and found it to be extremely low on the dipstick (I have photographic evidence of this condition). The vehicle had to be towed to Kate Faupel Chevrolet for further inspection. I was then informed that the engine has a dropped lifter on cylinder #8 and possible camshaft damage. Given the following factors: Recent out-of-pocket lifter and camshaft replacement (July 2025) Immediate failure shortly after leaving a Chevrolet dealership Extremely low oil level observed at the time of breakdown (with photo documentation) Diagnosis consistent with potential oil starvation and internal engine damage I am requesting that General Motors conduct a full review of this situation to determine responsibility. This raises serious concerns about a potential defect, improper prior repair, or a service-related issue that resulted in catastrophic engine damage. At this time, I am not authorizing repairs until liability is determined. I am requesting: A formal case review and investigation Assistance with repair or full engine replacement Guidance on how this situation will be resolved This incident created a significant safety concern, as the vehicle became disabled shortly after leaving a dealership during travel. Please contact me as soon as possible to discuss next steps

NHTSA ID

11734312

Incident

Apr 25, 2026

Vehicle is prompting a “decreased acceleration “ warning, will not shift past 3rd gear, and will not shift into reverse.

NHTSA ID

11733633

Incident

Apr 24, 2026

Suspension system failed- had to replaced, Car difficult to control when operating. Repaired by dealer- Country Chevrolet, Benton KY- owner paid for repair. [XXX] Engine failure- knocking and difficult to drive on returning trip from Louisville KY to Benton, KY. Taken to dealer on 4.6.2026 - made it without being towed- extremely slow- traffic hazard- Tahoe has lots of road miles- always repaired and serviced by dealer. There were no warning lights, symbols or indicators that there was a problem. Dealer still determining the extent of the damage. [XXX] Benton KY INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11730757

Incident

Apr 5, 2026

The component at issue is the engine, which suffered a sudden and catastrophic failure due to unknown causes. At no time prior to this incident were there any warnings, symptoms, or indications of an underlying mechanical defect that would have allowed for preventative action. While operating the vehicle on the highway with my family present, multiple warning indicators activated simultaneously, including a blinking check engine light, traction control light, ESC warning, and a forward collision warning. Immediately thereafter, the vehicle experienced a rapid and significant loss of power accompanied by a loud and persistent engine knocking noise, rendering the vehicle unsafe to operate and placing the occupants at risk. It is important to emphasize that traction control and ESC systems are not causally related to an engine misfire condition, further supporting that this event was abrupt and not part of a progressive or diagnosable issue. A diagnostic scan performed at that time identified a misfire in cylinder 1. Upon delivery of the vehicle to the dealership for inspection, it was determined that the engine had suffered complete internal failure and was deemed “blown.” This finding confirms the occurrence of a catastrophic mechanical breakdown. Based on the sudden onset, absence of prior warning, and severity of the failure, there is no reasonable basis to attribute this condition to normal wear and tear, operator misuse, or neglect. Rather, the facts support the conclusion that this was the result of a latent defect or internal mechanical failure beyond the operator’s control. Accordingly, this matter should be addressed under applicable warranty coverage or consumer protection standards.

NHTSA ID

11730632

Incident

Apr 5, 2026

During highway driving, alert on dashboard stated “electrical system failing enter idle mode”. Tahoe slowed down and then engine began knocking right as it shut off resulting in needing to coast to the shoulder of the highway safely since engine was off. Towed to dealership and then they came back saying needed a new battery, new alternator belt, pulley and water compartment. After those installed, additional call was made indicating the engine needed a full replacement as it keeps overheating despite no sensor alerts and codes are being tripped. Here we are asked to pay 16K for new engine install and unable to fix.

NHTSA ID

11730499

Incident

Apr 4, 2026

The contact owns a 2021 Chevrolet Tahoe. The contact stated that while driving approximately 45 MPH, the check engine warning light illuminated, and the message “Reduced Acceleration - Drive Safely” was displayed. The vehicle then started shaking abnormally. The contact pulled into a nearby parking lot, turned off the vehicle, and waited for a while before restarting the vehicle. After restarting the vehicle, the warning lights remained illuminated, and the vehicle continued to shake abnormally. The vehicle was taken to Auto Zone, where a certified mechanic diagnosed the vehicle and determined that there was a bent rod inside the engine. The vehicle was not repaired. The vehicle was taken to the dealer, who confirmed the diagnostic result and that the failure was causing additional damage to the crankshaft. The dealer determined that there was a misfire in the engine and that the valve lifter was malfunctioning. The contact was informed that the lifter and the camshaft needed to be replaced, and the engine needed to be repaired. The vehicle was not repaired. The contact researched and became aware of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the VIN was not included. The manufacturer was informed of the failure and confirmed that the VIN was not included in the recall. The contact was referred to the dealer to inquire about a Goodwill Repair for which the contact could be reimbursed if the VIN was later added to the recall. The manufacturer referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 100,000.

NHTSA ID

11729654

Incident

Apr 1, 2026

Mileage

100,000 mi

Motor is not included in the 6.2 recall for some reason. It is consistently burning through 3 qts of oil every 2-3k miles. This is a major concern considering I travel a lot. I want to know why this specific motor isn’t covered in the recall considering it is having the same issues as the current recall. This has been an ongoing issue and I have been waiting for a recall notice. GM dealership says there is no recall and won’t ever be one.

NHTSA ID

11729469

Incident

Mar 25, 2026

On March 14,2026 I was driving 80 MPH on the interstate and the vehicle shifted to Neutral and shutoff. Shortly before that the vehicle revved to 4000 RPM and you could feel rhythmic vibrations. The vehicle was towed to a Chevy dealership and diagnosed as loss of propulsion needing a new engine. Tahoe had 104,000 miles at failure.

NHTSA ID

11727248

Incident

Mar 14, 2026

I was driving down I-5 at 75mph and the truck shut off while driving. Couldn’t get to start. Paid over $1k for a new battery cause dealership couldn’t replicate problem. Next day doing 75mph on freeway engine through a rod.

NHTSA ID

11725417

Incident

Feb 9, 2026

Since March of 2025 I have identified a critical safety defect with my vehicle. When driving and without warning, the vehicle unexpectedly shifts to neutral, experiences a loss of propulsion, and the engine shuts off. This has occurred multiple times in which I narrowly escaped collisions with other vehicles or objects. If this would occur at a high rate of speed, it would certainly result in serious accident including possible fatality. I have experienced three near-accident scenarios when I had children in the vehicle. I have worked with Classic Chevrolet in Sugar Land, Texas who has made six attempts at repair. They have each time found a different component attribute to an error code and replaced that part. After each visit they tell me that the car is fixed and safe to drive. They have never been able to provide a clear explanation as to why I am experience this reoccurring issue, but attribute it to a different part each time. Within 5 days to 2 months, the incident repeats. I have recent video of the incident that I can share. Chevrolet Customer Care has been minimized my concern and informs me that their Service staff has found the vehicle to be fully operational and safe to operate. I have spent over $6,000 in failed repairs. I do not feel safe operating this vehicle. That list of repairs includes: March 7, 2025 - battery replacement March 28, 2025 - DC/DC power converter April 22, 2025 - ECM updates January 8, 2026 - •Throttle body replacement •Serpentine belt replacement •Engine air filter replacement •Transmission fluid flush •Coolant fluid flush •Fuel injection cleaning •Hydrogen carbon cleaning service January 23, 2026 - power control module (recall) January 30, 2026 - rear differential system replacement March 10, 2026 - • Replacement of the high-pressure fuel pump • Replacement of the DC power supply converter • Hydrogen carbon cleaning service I can share all invoices. Chevy is NOT TAKING THIS MATTER SERIOUSLY. Please support

NHTSA ID

11724504

Incident

Mar 15, 2026