2021 Chevrolet Tahoe: engine failure

Filed Nov 2, 2026 · Engine · NJ

Engine failure at2000miles, then at 80000

Filed Sep 23, 2026 · Engine · WA

The vehicle suffered complete internal engine failure due to a snapped timing chain on startup. The vehicle turned over via the starter motor but failed to start. A professional diagnosis confirmed the broken timing chain caused extensive valve-to-piston damage, requiring a full engine replacement. This failure appears to be a direct consequence of the known 6.2L L87 V8 engine crankshaft and connecting rod manufacturing defects. Severe mechanical resistance or violent rotational harmonics at the crankshaft level place un-engineered stress on the timing drive system, causing the chain to snap under startup torque. All broken components are preserved and available for inspection. The defect creates a severe risk of sudden, total loss of propulsion while driving. Had the compromised timing chain snapped at highway speeds rather than on startup, it would cause immediate engine seizure, a sudden loss of power steering, and a loss of power brake vacuum assist. This leaves the driver unable to accelerate or safely steer out of active traffic, creating an extreme risk of a high-speed crash.The broken timing chain and total engine destruction were officially diagnosed and confirmed by professional automotive repair technicians.The damaged components have been inspected by independent repair representatives. The vehicle has not yet been inspected by General Motors because this specific VIN is excluded from the current recall scope. There were no warning lamps, check engine lights, or diagnostic trouble codes (DTCs) prior to parking the vehicle, and no outward symptoms of severe engine stress were present until the complete no-start failure.

Filed Sep 13, 2026 · Engine · IN

DFM (Dynamic Fuel Management) system failure causing collapsed lifters, oil consumption, and complete engine failure. To repair our vehicle it will require a complete engine replacement. This has been a known issue with GM and yet there has been no recall to fix the issue. Now our engine must be replaced.

Filed Sep 8, 2026 · Engine · NE

Total engine failure. No warning lights shown and vehicle had been checked numerous times and reported as just fine.

Filed Sep 1, 2026 · Engine · KY

Engine failure Transmission failure

Filed Aug 28, 2026 · Engine · CA

Engine ceased to run. Two rods bent. No power. All engine lights on. Good oil pressure and oil level. Tahoe towed back to Simi Valley Chevrolet for engine replacement.

Filed Aug 24, 2026 · Engine · VA

Nearly new Chevrolet Tahoe in 2021 with less than 4,000 miles had an engine failure due to defective valve lifters that required a significant repair and lengthy out of service period (replaced valve lifters in one bank). Now in 2026 the same vehicle's engine has failed for the same reason and the engine needed to be replaced.

Filed Aug 22, 2026 · Engine · MO

Engine failure of the 6.2L L87. Was 12 hours from home with my family on vacation in Colorado cruising up a 4 lane mountain highway about 700 yards from entering [XXX] thru the mountain and the engine started screaming and knocking. Thank the lord there was a way I could quickly steer my vehicle and family off the 65 mph hwy. Engine had recently passed the recall inspection test. “3,000ish miles ago” dealership confirmed engine failure and it’s sitting in cooorado waiting for a replacement engine. I believe this will be the 3rd engine now in my car. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Aug 22, 2026 · Engine · SC

6.2L engine failure. Camshaft and lifters. My [XXX] wife ([XXX]) was driving and it shut off going down the highway. It is at my local Chevrolet dealer getting repaired. No warnings. No engine light. Vehicle has 88,000 miles on it, I purchased it April 22, 2026 with 84,700 miles on it. My Chevrolet App says there are no issues with the vehicle..it’s in pieces at the dealership. I had higher standards for a high country. Always owned Chevrolets. May be my last one. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Aug 4, 2026 · Electrical, Engine · MD

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 the federal safety agency Campaign 25V274 / GM number N252494000 however the car has been deemed to not be covered with mileage at 139,300.

Filed Jul 2, 2026 · Engine, Fuel system · IL

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.

Filed Jun 30, 2026 · Engine · NJ

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