2021 CHEVROLET SILVERADO 1500 reports

POWER TRAIN

See attached document for complaint.

ENGINE

The truck shut down while on the highway, complete loss of power and would not restart. Chevrolet dealership concluded that the engine has locked up/failed. Chevrolet states that 2021 6.2-L L87 engine is not included in Recall 25V-274 despite similar mechanical failure.

POWER TRAIN · ENGINE

internal engine failure: Lifter went out. Hence caused a catalytic converter to fail without my knowledge. Obviously with this issue there is an issue and can potentially be more. This would be under a recall.

ENGINE

Took my truck 2021 Chevy Silverado 1500 6.2 to GMC for engine noise and was told my engine needs to be tore down to replace the camshaft and lifters for $11,000 or I could replace the engine for around the same cost. Truck doesn’t fall under the 6.2 recall even though this is one of the issues that the motor has been recalled for?

POWER TRAIN · ENGINE

The lifter on my cylinder one is failing. This is a known issue with the Chevrolet 5.3L 8cylinder engine and 2021 models are known for being notoriously bad with lifter issues. My safety and the safety of other drivers that own 2021 Chevrolet models is impacted due to this issue can cause the engine to completely fail and shut off while driving which could cause severe injuries up to death. The problem is a widespread issue and mine was confirmed by an independent service mechanic. The vehicle is now being inspected by the dealership. The issue did not arise until I reached 104,000 miles.

ENGINE

I bought this vehicle 9/2023. On 02/23/2024, I started my truck, and heard a very loud knocking noise upon starting it. I turned it off. Called the dealership to come pick it up. They were able to repair it, by repairing some of the lifters on one side. Fast forward to 10/25/2026, I started my truck and heard the same knocking noise. Called the dealership to come pick it up. They say my truck is no longer covered under the power train warranty, and it will cost $10,000 to replace the other side of lifters and cam shaft.

ENGINE

On October 18, 2026, I was driving my 2021 Chevrolet Silverado 1500 with the 5.3L V8 engine at highway speeds with my wife and two young daughters in the vehicle when the engine suddenly lost power and the truck began shaking violently. The check engine light flashed, and "Service ESC" and "Service Parking Brake" warnings appeared on the dashboard. The sudden loss of power at highway speeds created a serious safety risk to my family and surrounding motorists. I was able to get the vehicle off the highway safely. Restarting the truck did not resolve the issue, and it was no longer drivable. The truck was towed by a AAA contractor to a Chevrolet dealership. Following inspection, the dealership verbally diagnosed a broken camshaft and advised that the entire engine required replacement. The truck had approximately 98,000 miles at the time. A written diagnosis has been requested, and the vehicle is currently at the dealership. The truck has a documented history of engine problems. In July 2023, at approximately 33,500 miles, a Chevrolet dealership diagnosed code P0300 and documented misfires on cylinders 1, 3, and 7. Warranty diagnostic and repair work was performed. Another check engine light concern was documented in November 2024 at approximately 62,300 miles. In April 2025, at approximately 69,600 miles, Chevrolet again investigated a P0300 multiple-cylinder misfire condition. Beginning around 75,000 miles, the truck also began displaying recurring low-oil warnings. I added oil whenever these warnings appeared and maintained regular oil changes, supported by service records. Despite these prior engine concerns and dealership visits, the engine suffered a catastrophic failure without an immediate warning before reaching 100,000 miles. I am concerned about the potential for sudden engine failure and loss of propulsion at highway speeds and believe this warrants a safety investigation.

ENGINE

The contact owns a 2021 Chevrolet Silverado 1500. The contact stated that while driving the vehicle at highway speeds, the vehicle shut off and lost power. The vehicle failed to accelerate and coasted off the interstate to a safe stop. The contact stated that several warning lights were illuminated on the instrument panel while the vehicle was losing power. The contact stated that two days prior to the failure, the vehicle was taken to an independent mechanic for an oil change, and there was no failure found. The manufacturer was notified of the failure. The vehicle was towed to the dealer where it was diagnosed with engine failure. The contact was informed that the engine needed to be replaced. The failure mileage was 79,000.

ENGINE

My truck experienced a sudden catastrophic engine failure at highway speeds. It is directly related to the current recall on L87 gm engines and has the same symptoms but is not covered under the current recall. The crankshaft failed thus causing the timing chain to break completely destroying the engine.

ENGINE

I was cruising down the highway at 55mph when the engine suddenly shut off. I took it to a mechanic who said the engine suffered a catastrophic failure and would need replaced. The truck only has around 93,000 miles on it and should definitely be looked into. The vehicle has always been very well maintained.

ENGINE

My 6.2L is experiencing engine knocking. Sounds like ball bearings rolling around at idle and acceleration. Its been seen by GM dealer and they notice "something" isnt right but say its not part of recall at this time. They want it to fail more before pursuing.

ENGINE AND ENGINE COOLING

The contact owns a 2021 Chevrolet Silverado 1500. While driving approximately 35 - 40 MPH, the check engine warning light illuminated, and the vehicle lost automotive power. The contact parked and restarted the vehicle; however, the RPM fluctuated and the failure persisted while driving. The vehicle then failed to restart and was towed to the dealer and DTC: P0016 was retrieved. The failure was associated with NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the VIN was not included in the recall. The manufacturer was notified of the failure by phone. The failure mileage was approximately 85,000.

SUSPENSION

last October 2025 while going a slow rate of speed my passenger front ball joint severed and this past 17 oct 2026 my driver side ball joint broke also going a slow rate of speed after turning onto a highway.

ENGINE AND ENGINE COOLING

The contact owns a 2021 Chevrolet Silverado 1500. The contact stated that while driving 60 MPH, the check engine warning light illuminated. The vehicle was taken to the dealer, where it was diagnosed that the engine coolant control valve had failed and required replacement. The vehicle was not repaired. The VIN was not included in Special Coverage Program: N252508341 (Coolant Control Valve), nor was the VIN included in the associated technical service bulletin. The contact stated that the failure occurred on several occasions. The manufacturer was not notified of the failure. The failure mileage was 77,000.

UNKNOWN OR OTHER · ENGINE

Coolant control valve Is available for inspection Safty issues include Loss of power steering and brakes while driving Sudden power limp mode Sudden engine over heating and engine seizure Loss of visibility due to smoke and Loss of defrosting Inspection done by chevolet (live oak Fl) Check engine light and code p1098 appeared after defect.

ENGINE

Chevy Silverado 1500 6.2L Truck lost acceleration while driving. Truck advised driver to shift to neutral and restart vehicle. When driver did, no resolve. Error code with diagnostic report was immediately emailed to owner with error code of P0016. Mechanic advises truck needs new engine as this is a common issue with this year of truck that was included in a recall. After further investigation, truck vin is NOT included in recall as other GM vehicles (same engine & year). Would like this investigated as this truck should be included with the recall.

ENGINE

Chevrolet Silverado 1500 6.2L Truck was driving and fully lost capability to accelerate. Truck alarmed driver to shift to neutral and restart engine. Attempt to restart engine was not successful. Error code was sent via email in a diagnostic report to owner with code P0016. No check engine lights or alarms were on the dash. Truck is currently at an auto mechanic. Safety issue was leaving driver and passengers stranded. Auto mechanic states truck needs new engine. Tried to verify VIN to the GM recall notice (N252494000) and was told not included in recall, even though truck has same motor listed in recall AND giving the error code. There was no warning messages, lights or symptoms prior to this failure. Request to have this complaint investigated to be included in the recall with the information provided.

STEERING · ELECTRICAL SYSTEM · UNKNOWN OR OTHER

While driving approximately 30–40 mph through an uphill left-hand curve, the steering suddenly became extremely stiff and very difficult to turn. I do not recall seeing any warning before I noticed the steering becoming stiff. While trying to control the vehicle, I noticed “Service Power Steering” and “Service ESC” warnings approximately 1–2 seconds later. I cannot say exactly when the warnings first appeared because everything happened very quickly and I was focused on trying to control the vehicle. The vehicle left the roadway onto an adjacent lawn and traveled along a steep hillside beside the road. The driver-side mirror struck a curve sign and broke before the vehicle returned to the roadway. The vehicle also bounced while traveling off the road, and there is additional visible body damage. I do not yet know whether there is hidden steering, suspension, underbody, or other damage. A passenger was in the vehicle and witnessed the incident. Shortly afterward, while taking the passenger home, the steering again became extremely stiff and I again noticed the Service Power Steering and Service ESC warnings. Because the steering problem occurred twice, I parked the vehicle and have not driven it since because I do not believe it is safe to operate. The vehicle has not yet been professionally diagnosed or repaired and remains available for inspection. I have opened a case with the manufacturer. There were no known steering problems before this incident. The vehicle had an alignment performed earlier the same day

ENGINE · FUEL/PROPULSION SYSTEM

On my way home to [XXX] from [XXX] around XXX, my 2021 Chevy Silverado with 84,xxx miles with the 6.2 L engine started to make a popping sound. I checked my dash for any error codes and there were none. The oil pressure, temp, and transmission temp gauges all read normal. I stopped and topped the gas tank off with premium gas and checked the oil level, which was good. I was able to limp the truck back to my house. The next morning when I started it, there were error codes and the engine was still making the popping noise as well as a louder knocking noise. I started researching the symptoms, called two local independent shops and concluded the DFM system that shuts cylinders off to conserve gas has failed and caused the lifters to fail. I was told the failed lifter could and probably did damage the cam shaft(s). If I kept driving it, the camshaft damage could cause complete engine failure and more safety consequences. One shop quoted $5000 to replace lifters and $8000 if the camshafts were damaged. The other shop was similar, but offered a rebuilt engine for $12,000 because the lifters, camshafts, and new GM crate engine were all back ordered with no ETA from the local Chevy dealership. After weighing my options, and needing a truck, I decided to trade in my damaged truck. I contacted the GM concierge on XXX and was told to call back when the dealership had my damaged truck and could diagnose it. On XXX I called them back and they said they wouldn’t help because I traded it in. I had no plans to trade it before the engine failed and took a substantial hit on the trade in price that GM should have helped with to cover their faulty DFM system that caused the lifters to fail, which the dealership confirmed was the problem. They said they wouldn’t know if the camshafts were damaged until they took it apart, which they decided to not do and send it to auction instead. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE

2021 Chevrolet Silverado 1500 with the 6.2L V8 (RPO L87), built November 2020. Mileage at failure: 11268. On XXX the check engine light came on with DTCs P0011 and P0016. The engine developed a rattle at startup and when lifting off the throttle around 40 mph. On XXX Fowler Chevrolet ([XXX]) isolated the abnormal engine noise to the crankshaft bearings. Cutting open the oil filter showed excessive bearing material. The dealer advised engine replacement before complete engine failure and quoted $12,561.66. This is the same failure described in recall 25V-274 (GM N252494000): crankshaft/connecting rod bearing failure in the L87 engine, which can cause loss of propulsion while driving. My VIN is not included in the recall because it was built before the XXX start of the recall build window. The engine is the same L87 and failed the same way. The vehicle has been maintained with regular oil changes and I have records. GM Customer Assistance case XXX was opened XXX. The vehicle is currently not safe to drive due to risk of engine seizure and loss of motive power. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

POWER TRAIN

2021 Silverado with 5.3 engine/8spd transmission/38,000 miles just outside of the 5-year powertrain warranty *No current recalls under this VIN as of 10/07/2026* Undiagnosed issues with symptoms similar to transmission or rear end slippage, torque converter or clutch pack problems. No warning lights or messages have appeared 1) Vehicle seems to hunt for proper gearing between 30-40 mph (3rd to 4th gear) with light shuddering before shifting gears. Occurred 20+ times 2) Sudden jerk when taking off from dead stop. Feels like being lightly bumped from behind then drives normally. Occurred 4 times 3) Only noticed when towing appx 6,000lb trailer descending down a hill - A one-time loud clunk when easing off throttle and coasting downhill. The sound is similar to hitting a metal desk with a fist. Occurred 7 times. Spoke with local Chevrolet dealer who informed me the powertrain warranty has recently expired, and no repair cost would be covered. Recommended dealer service would be to replace the transmission fluid and filter with Mobil 1, potentially reprogram the transmission, and replace the torque converter. All on a vehicle with only 38,000 miles

STEERING

While driving vehicle service power steering light came on had no power steering had to wrestle steering wheel no power steering a smaller person would not have able to handle it

ENGINE · FUEL/PROPULSION SYSTEM

I was traveling on a 55mph road. My Chevy Silverado started to shake and lose propulsion. I pulled off on the side of the road. In idle it shook. The dealership was one mile to my south. I turned on the hazard lights and went to the dealership. I could only get the vehicle to 45mph as in shook very bad the whole way. It felt as if the engine was going to explode the whole way there. The vehicle was taken to the dealership where it has been initially diagnosed as a bad lifter.

ENGINE

The contact owns a 2021 Chevrolet Silverado 1500. The contact stated that while driving at an undisclosed speed, the vehicle was smoking. The contact stated that the engine was smoking heavily with a strong oil odor, before the vehicle shut off. The contact stated that the engine warning light was illuminated. The vehicle was restarted and driven to the dealer. The manufacturer was notified of the failure. The vehicle was taken to the dealer, and the technicians confirmed the engine failure. The contact was informed that the engine needed to be replaced. The vehicle was being repaired. The failure mileage was 78,000.

ENGINE

The contact owns a 2021 Chevrolet Silverado 1500. The contact stated that while driving approximately 35 to 40 MPH, the vehicle stalled and failed to restart. The contact retrieved DTC: P228C and P030 after scanning the vehicle. The vehicle was towed to a service center, where the contact was provided DTC: P228C, P0340, and P0C6. The contact was informed that the timing chain and guide had failed and that the engine needed to be replaced. The vehicle was not repaired. The failure mileage was approximately 172,000.

SUSPENSION

Ball joint Failure of front passenger wheel assembly Wheel literally folded under truck . Both ball joints broke . 64k miles luckily I was only doing about 20 mph .

POWER TRAIN · ENGINE · FUEL/PROPULSION SYSTEM

I am submitting this complaint regarding a 2021 Chevrolet Silverado 1500 Trail Boss 4WD with the [6.2L V8 (L87)], VIN [XXX], 101,000 miles. The truck was assembled in Mexico in XXX, about six weeks before XXX, just outside the build range of GM recall 25V-274 (N252494000, Engine Failure). On 10/2/2026, [XXX], [XXX] a certified GM dealership, diagnosed crankshaft and lifter failure, matching the recall condition. Codes: P0300, P050D, P0016. The truck was shaking violently, the ESC and emergency braking system failed, reducing engine power. GM's Part 573 filing attributes the defect to out-of-specification crankshafts and identifies a Mexico-based crankshaft supplier. I ask GM to confirm my engine's build date and crankshaft source. A six-week gap in build date should not exclude a truck with the same failure. Engine failure can cause sudden loss of power while driving, a safety risk. The dealer quoted repairs of up to $10,292.00. I request: That GM cover the repair in full as a goodwill adjustment. That GM and NHTSA review expanding the recall population to trucks built near my date. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

POWER TRAIN

6.2 L engine failure oil related. Had to replace engine.

ENGINE

The contact owns a 2021 Chevrolet Silverado 1500. The contact stated that the vehicle experienced excessive oil consumption at 2,600 miles. The vehicle was taken to the dealer, where it was diagnosed with a blown engine. The engine was replaced; however, the contact stated that the replacement engine continued to consume a significant amount of engine oil. The vehicle was taken back to the dealer, where the replacement engine was diagnosed with premature engine failure at 37,100 miles. The contact stated that during the engine failure, there was an abnormal sound coming from the engine and transmission. The manufacturer was notified of the failure. The contact stated that the vehicle had been taken to the dealer every 1,000 miles for oil to be added due to the excessive oil consumption. The dealer confirmed the initial engine failure and the premature failure with the replacement engine. The failure mileage was 37,100.

ENGINE

My truck is the 2021 with the 6.2l L87 motor. My truck is not in the scope of the recall but i had the same failure and received a remanufactured engine without any warranty coverage.

POWER TRAIN

The contact owns a 2021 Chevrolet Silverado 1500. The contact stated that the vehicle previously had a bell housing installed to catch internal metal shavings; however, the housing assembly failed again and needed to be replaced. The vehicle was taken to a dealer for a diagnostic test. The contact associated the failure with the torque converter. The torque converter was previously replaced once. The contact stated that while driving, the vehicle felt like it was driving over rumble strips or speed bumps, which the contact felt and heard. The manufacturer was notified of the failure. The dealer was unable to duplicate the failure. The failure mileage was 60,000.

POWER TRAIN · ENGINE

This vehicle's engine failed on a high-volume roadway in [XXX] which resulted in a significant safety issue. The vehicle was taken to a certified Chevrolet dealership in Scottsdale (Van Chevrolet) whereby the engine in this 5.3L V8 was replaced due to catastrophic engine failure with the lifters being the suspected cause of the failure. Aside from the $10,400 cost of the remanufactured engine replacement, I have had considerable discussions (live and written) with GM Arizona and Corporate representatives outlining the issue(s) and filing formal complaints. These have gone relatively unheeded... Unfortunately, this is the second 5.3L V8 engine failure in one of our GM vehicles as I will be filing yet another formal complaint under separate cover for a 2021 Tahoe 5.3L V8 which had an engine failure requiring new lifters. I am not done yet as I have an appointment tomorrow for what appears to be, a third Chevrolet vehicle with a 5.3L V8 engine lifter failure. Depending on the outcome of this service appointment, I may be filing a third safety complaint regarding the GM 5.3L V8 engine. In my opinion, the NHTSA should absolutely open an investigation into this engine in the same manner that you have a formal investigation/recall in effect for the 6.2L GM engine as based on two personal experiences, the safety of the driver and passengers in these vehicles is compromised due to what appears to be significant engineering and/or manufacturing issues on the part of General Motors. Thank you for your consideration and I am free to discuss in further detail at [XXX] or [XXX]. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

POWER TRAIN

Vehicle has a bad valve body which was confirmed by the dealer. Driving down the street and the engine went from 3 to 4 gear and the rear wheels locked up. Also when coming to a stop the truck jerks so bad it snaps your neck. GM has major problems with these trucks and knows the problems and keeps issuing bulletins however they have a massive backlog of orders for parts to fix these trucks which leaves people's trucks sitting at service centers for months waiting for backordered parts

FUEL/PROPULSION SYSTEM

Truck stalled out while driving as if it had run out of fuel. Had to be towed to my house

ENGINE

the engine seized. I tore into the motor to inspect what caused it and it spun a connecting rod bearing on cylinder 1. I have been paying 600 a month on it without being able to drive it since this happened in november of 2024.

STRUCTURE

According to 2 mechanics- including a body shop - the frame has prematurely rusted due to: TSB 19-NA-255 - Wax Coating on Frame Peeling, Metal Shows Corrosion/Rusting There's so much damage to a 2021 truck, that it may not survive this winter. The frame welds are breaking due to the lack of frame protection. I asked my dealership, Lamoille Valley Chevrolet 868 VT RT 15E HYDE PARK, VT 05655, on two separate occasions to check for damage. One time they made no report, the second time they told me it was normal wear and tear. I've been told trucks 20 years older than mine, are in better condition. There was no protection for this frame.

POWER TRAIN

The contact owns a 2021 Chevrolet Silverado 1500. The contact stated that after activating the 4WD feature, the rear wheels locked up with the check engine warning light illuminated. The vehicle was taken to the dealer on several occasions to be diagnosed. Several unknown parts were replaced; however, the failure persisted. The vehicle was not repaired. The contact referenced Safety Recall : N242454440; as a possible cause for the failure. The manufacturer was not notified of the failure. The failure mileage was 102,490.

POWER TRAIN

Around 60k miles my truck started shifting rough and at odd times. Then it went into “limp” mode. I took it to the dealership and they replaced my battery and a solenoid. I asked about the transmission and they told me it was because it was in “limp mode”. I’ve continued to have issues with it then a couple of months ago while driving to work at around 60mph the truck harshly downshifted into a low gear causing the rear tires to break loose on the wet roads and sending me into an extended spin. I had the truck towed home and then to the local dealership. After researching, I have found that this is very common with the same vehicles in this year and that there are multiple recalls to address the issues. Unfortunately my VIN is not included. I believe the needed repairs and the associated costs should be GM’s responsibility under special coverages: N242454441 and N242454440-03

ENGINE

The water pump went bad at 31,000 miles. If I continued driving and the pulley fell off the engine would overheat. I took it to the dealer and they confirmed the pump failure and want me to pay over $1,400 for repair that should be covered under warranty. There was no warning lamps lit, the pump just started making a grinding sound.

UNKNOWN OR OTHER · ENGINE

My truck started skipping and over time the check engine light came on. I took it in and they are saying it is the lifters, which is costly. I know this truck was built during COVID and I know a lot of the manufacturers were dealing with skeleton crews. I heard this was an issue with the 2021 Silverado trucks, and a recall. Can you please advise?

ENGINE

Engine failed and truck caught on fire from the engine failure

POWER TRAIN · ELECTRICAL SYSTEM · ENGINE

2021 silverado engine failure. Yes it was inspected by a dealership and my extended warranty company and serviced by the dealership. Back on August 5th I experienced a misfire cylinder 3 and felt loss of power. On August 7th the dealership diagnosed both camshafts, 1 lifter, 1 valve, and 1 fuel injector was damaged and never received at warning lights or messages on the dashboard. I was without the vehicle for 39 days and within 10 hrs after picking up the truck i got an engine light on and several new codes on it and can not be driven and being towed. I feel these engines need a recall as it is well documented that these engines go between 60 and 80,000 miles and some a lot less than that, mine has 70,800 and went and now being towed with in less than 24 hrs after engine repair. I will be in contact with a lawyer to follow up on this matter.

ENGINE

Engine noise, unable to pass or fail pico test due to to much noise in truck. Engine failure.

ENGINE

LM2 engine coolant control valve failure. My vehicle VIN is not listed for the repair i dont know how it is not but they want me to pay outa pocket

STRUCTURE · ENGINE

Statement for NHTSA Subject: Safety Complaint – 2021 Chevrolet Silverado Unexpected Jerking/Harsh Transmission Engagement I am submitting this complaint regarding my 2021 Chevrolet Silverado 1500 2.7L Turbo with approximately 128,000 miles. My vehicle has developed a recurring problem involving harsh/jerking transmission engagement, hesitation, shuddering and abnormal shifting. The truck can jerk when engaging or changing gears and has also experienced a hard engagement when shifting from Reverse into Drive. During normal driving, the vehicle can hesitate or feel as though it is repeatedly fluttering/shifting instead of providing smooth and predictable acceleration. The vehicle has produced diagnostic trouble codes including P0700, U0100 and P0420. I am concerned that this condition could create a safety hazard, particularly if the vehicle unexpectedly jerks, hesitates or fails to respond normally when accelerating or changing gears in traffic. I am requesting that NHTSA document this complaint and review whether there is a pattern or potential safety-related defect involving transmission engagement, shifting or drivetrain control on 2021 Chevrolet Silverado vehicles. GM has published service information concerning delayed and harsh transmission engagement on certain Silverado applications, including 2019–2021 models, which makes me concerned that my vehicle may be experiencing a related issue. I am retaining my repair records, diagnostic information, receipts, videos and mileage/date information documenting when the problem occurs. I am willing to provide this information if requested. Please help me get my truck corrected, I love my Chevy Truck. Thanks Sincerely [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE

Following recall review by the dealership, experienced sudden, catastrophic engine failure nearly stranding me on the road with my son. Awaiting final diagnostics from the dealership, but every indication, errors, and symptoms align with all the other complaints that I have reviewed on line for the make/model of my vehicle. Recall assessment and corrective actions ineffective resolving engine failure.

ELECTRICAL SYSTEM · ENGINE · FUEL/PROPULSION SYSTEM

My 2021 Chevrolet Silverado 1500 RST with the 6.2L engine experienced an engine seizure. The engine was replaced by a Chevrolet dealership under a GM safety recall. Immediately after picking up the vehicle following the recall engine replacement, the truck stalled while still in the Chevrolet dealership parking lot. There was no warning before this first stall. We continued our trip because we did not realize at the time that the stall could indicate a problem following the engine replacement. During the drive from [XXX] to [XXX], the problem continued. In [XXX], the check engine light illuminated and the truck began malfunctioning. The vehicle subsequently stalled again. The problem continued after returning to [XXX]. A Chevrolet dealership in [XXX] inspected the vehicle and reproduced/confirmed a problem involving the camshaft position sensor wiring/connector. The dealership demonstrated the problem by manipulating the connector/wiring and recorded a video of the diagnostic procedure. The vehicle is currently at the Chevrolet dealership and is available for inspection. The affected component should also be available for inspection because it has not yet been repaired. The [XXX] dealership has characterized the wiring/connector condition as normal wear. However, the first stall occurred immediately after the GM recall engine replacement, while the vehicle was still on the repairing Chevrolet dealership's property. Unexpected engine stalling creates a serious safety risk because the vehicle can lose propulsion without warning while driving, including at highway speeds or in traffic. I am concerned that the camshaft position circuit/wiring/connector problem may be associated with the recall engine replacement procedure or replacement engine. I am requesting that NHTSA investigate whether other vehicles receiving this GM 6.2L engine recall remedy have experienced similar camshaft position circuit failures or unexpected stalling after engine repair. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

POWER TRAIN

The contact owns a 2021 Chevrolet Silverado 1500. The contact stated that while driving 40 MPH, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. The contact stated that the transmission was slipping while shifting gears and the transmission was shuddering. The dealer was contacted by phone and made aware of the failure. The vehicle was taken to the dealer, where it was diagnosed with transmission failure. The contact was informed that the transmission needed to be replaced. The vehicle was not repaired. The contact was informed that the parts were ordered. The manufacturer was contacted by phone and made aware of the failure, and a case was filed. The contact was informed that the warranty had expired five months prior. The failure mileage was approximately 53,020.

ENGINE

Loss of power , catastrophic engine failure

ENGINE AND ENGINE COOLING

The contact owns a 2021 Chevrolet Silverado 1500. The contact stated that while attempting to start the vehicle, there was an abnormal sound coming from the front driver's side of the vehicle. The contact inspected the vehicle and became aware that the exhaust manifold bolts had detached. The dealer was made aware of the failure. The contact was informed that the warranty mileage limitation had been exceeded. The manufacturer was contacted by phone, and a case was filed. The contact was advised to contact the NHTSA Hotline to report the failure. The failure mileage was approximately 62,248.