2021 Chevrolet Silverado 1500 Powertrain (other) Problems

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.

NHTSA ID

11766400

Incident

May 14, 2025

Mileage

102,490 mi

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

NHTSA ID

11765787

Incident

Jul 21, 2026

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.

NHTSA ID

11764947

Incident

Aug 5, 2026

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.

NHTSA ID

11763159

Incident

Sep 7, 2026

Mileage

53,020 mi

While driving on the road, the transmission in my truck completly neutralized all the gears (meaning it just started revving and slowing down rapidly in the middle of the road with cars in front of and behind me). And almost got me hit by several cars. I got the vehicle towed to the Chevy dealership it was bought from. The mechanics then confirmed the code was for a failed valve body in the trucks transmission. Which they had recalled in all the diesels but not gas engines.

NHTSA ID

11761775

Incident

Aug 22, 2026

Engine failure , early on it had the dod replace. Under warranty and I’m not 100% sure but this time it failed and took out the engine. New rotating system and valves replaced Happened at just under 100k miles With all I’m seeing about these engines I figured I’d report it.

NHTSA ID

11760706

Incident

Nov 1, 2025

About 2 months after bringing the truck in for the engine recall, my oil cooler blew up and I required that to be replaced, along with the radiator and hoses.

NHTSA ID

11760698

Incident

Jul 12, 2026

My husband was driving his 2021 Chevy Trailboss when it went into limp mode. It had to be towed to the dealership and it was uncovered that his truck was throwing out codes P0700 P2732 which is a known issue with this truck, resulting in internal valve body hydraulic failure. Since his vehicle is at 70k miles, and over the 60k, the dealer is pushing back and trying to say they don’t have to cover it. GM states that we should pay and then submit a reimbursement form. This is a $3800 fix. This is not our responsibility and this is unsafe. This should be a safety recall for all vehicles of this make, model, and with this transmission. Additionally, he had to have his engine replaced on this truck (we bought it brand new in 2021) with only 10k miles on it. This truck should not be built anymore and anybody facing these issues should not be held liable for them. This is a manufacturing issue and it is only one company’s fault, General Motors!

NHTSA ID

11760115

Incident

Aug 17, 2026

Vehicle bucks upon acceleration in the rear end. Dealer recommends replacing the transmission.

NHTSA ID

11758018

Incident

Aug 7, 2026

Shuddering at 25 to 50 mph, harsh shifts, hesitation.

NHTSA ID

11757759

Incident

Aug 18, 2026

On August 22, 2025 the malfunction indicator lamp (code: P146B Evap. purge pump) illuminated with no noticeable change. Ran codes at auto zone which stated engine failed and emissions not ready. August 25, 2025 drove to certified Chevy dealer dropped off vehicle and showed the service advisor the fix finder test results from auto zone as well as the illuminated indicator lamp (check engine light). August 26, 2025 picked up my vehicle with receipt stating "found dtc's P146b and P1467 stored in ECM (engine control module) for evap purge pump fault. inspected evap canister for any signs of fuel and none were found. replaced evap purge pump per special policy #N232395310. Cleared dtc and road tested vehicle to verify repair". September 9, 2025 my engine indicator light illuminated and my engine entered limp mode, a safety feature which reduces cylinder output/capacity. September 12, 2025 while in limp mode, I returned to the service dealer and informed them of the reduced power (limp mode) and my confusion as the second engine symbol that has been illuminated is in a different area than the first and my truck has ONE engine. (editor note: malfunction indicator lamp is for the emissions). My original transmission (8L90) was replace, because my vehicle was under power train warranty and the service advisor took it upon himself to approve the disassembly of my running, in good condition 8L90 transmission without consulting me or my approval. the 8L90 was "discontinued" for the 2020-2022 years without recall come to find out (sarcasm). I now have a new transmission (8L86-85) with the "special coverage" part (#N232395310) still connected, only now I have NO additional powertrain coverage for a new transmission, but the "special coverage" originally issued in 2023, BY MAIL, for 15 yr/150,000miles has extended two years plus mileage. (15 yr / 152,955) .The "special coverage" part should NOT affect the engine! Engines produce power/HEAT not CO2 . Sarbane - Oxley Act.

NHTSA ID

11755329

Incident

Aug 25, 2025

The contact owns a 2021 Chevrolet Silverado 1500. The contact stated that while driving at an undisclosed speed, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. The contact stated that there was an abnormal sound coming from the vehicle and the vehicle was jerking erratically. The contact stated that the transmission was shifting hard, and the vehicle drove abnormally rough. No warning lights were illuminated. The vehicle was taken to the dealer; however, the failure was not duplicated. The failure was persistent. The manufacturer was not made aware of the failure. The failure mileage was approximately 49,000.

NHTSA ID

11754700

Incident

Aug 13, 2024

Mileage

49,000 mi

2021 Chevy Silverado 5.3 trail boss lifters has failed on this driver two times while driving on highway engine lost power with my family in the vehicle. Dealer warranty fixed lifter the first time lifter went out at 1100 miles. The vehicle has failed again with multiple lifters going out and camshaft needing being replaced also on my extended warranty at 73000 miles. I do not want to take this vehicle back in my possession as it has put me and my family at risk twice being stuck on highway with no power.

NHTSA ID

11754540

Incident

Jul 17, 2026

On or around XXX a my 2021 Silverado started making a rattling sound from the engine. The truck began to stall and the engine shut off three times while driving. I attached scanner the next day and the track showed P00011 and P00016 codes. Those codes are for the Camshaft Sensor and the Crankshaft Sensor. I went online and did research about the two codes and discovered there had been a couple recalls for these codes concerning my year model truck: (Recall Number 25V-274; GM: Campain N252494000). NHTSA Engineering Analysis EA25007 or RQ26001 I spoke with the Dealer I purchased vehicle from (Lynn Layton Chevrolet - Decatur, Al)and they said they will not begin repairs until they receive payment from GM or myself. I then spoke with Tyler at GM Corporate Customer Service. He said my VIN was not included in the GM Campaign|Recall. I asked why not because it is a 2021 Silverado and I’m having the exact same problems as vehicles included in the recall. He said because they checked their system and the parts used on my truck were from a different manufacturer than those included on the recall. I said that shouldn’t matter because my truck is having the same exact problems. I asked him to check and see if GM would be able to provide financial assistance to have motor repaired or replaced. Tyler told me that GM will not do repairs - they will only replace the engine. He said GM would not provide any financial assistance because my truck has 170k plus miles on it. I informed Him that I had previously taken my truck to Lynn Layton Chevrolet about these symptoms and it was diagnosed as transmission/torque converter problem. They changed transmission fluid and charged me ~$700. I then asked if GM would authorize a “Goodwill Replacement”. He said they would not. I called Lynn Layton Decatur back and asked how much would engine and reps if I have to pay for it. They said 10k -12k A local mechanic said he will fix for $6,000. Please help me get this resolved. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION

NHTSA ID

11753677

Incident

Jun 10, 2026

The contact owns a 2021 Chevrolet Silverado 1500. The contact stated that while driving approximately 30 - 60 MPH, the transmission failed to shift properly, and the vehicle hesitated while depressing the accelerator pedal. A dealer was contacted. The vehicle was taken to the dealer to be diagnosed, and the contact was informed that the valve body needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline to report the failure. The approximate failure mileage was 105,000.

NHTSA ID

11753288

Incident

Jul 17, 2026

Mileage

105,000 mi

Transmission needs to be replaced at 77000 miles!! A KNOWN problem with this make/model/year and NOTHING is being done!!!!!!!!!!!!!!!!

NHTSA ID

11750803

Incident

Jul 16, 2026

I have a 2021 Chevrolet Silverado 1500 with a 3.0 Duramax diesel engine, Have had a check engine light intermittent a couple times. Vehicle went into limp mode. Had the diagnostic code read; P1010. Code P1010 shows an engine coolant flow control valve position sensor exceeded minimum learning limit. General Motors has issued a special warranty N252508341covering 2021-2023 Silverado 1500 for this part ( LM2 coolant control valve replacement ) with a 15 year and 150,000 mile limit. I took my vehicle to the Chevrolet dealer and they said my VIN number was not covered. It would be a $1900 repair. I have read of numerous other of same vehicles listed under the special warranty, yet GM has excluded these VIN numbers as well. This is a known defect, GM has covered some but not all. Yet many are NOT covered yet having the same problem. I am not able to reach anyone at GM to talk about this issue. It needs to be addressed.

NHTSA ID

11748870

Incident

Jul 6, 2026

Transmission shutter at low speed acceleration

NHTSA ID

11747289

Incident

Jun 1, 2026

My 2021 Chevrolet Silverado RST 4x4 5.3L V8 was a Certified Pre-Owned vehicle purchased through a GMC dealership, strictly maintained by certified GMC service departments, and had its torque converter replaced one year prior in accordance with a manufacturer Technical Service Bulletin (TSB). One week before a scheduled round-trip journey from Alabama to North Carolina, the truck underwent a comprehensive multi-point inspection, oil change, and tire rotation at an authorized Chevrolet dealership. While driving on the highway, I came to a complete stop due to an accident ahead, but when traffic resumed a forward-moving pace, the drivetrain completely lost the ability to propel the vehicle without any prior warning signs or symptoms of mechanical failure. While immobilized and contacting 911 and towing services, I attempted to cycle through all drive modes—including Auto, 4-High, 4-Low, and 2WD—but none succeeded in transferring power to the wheels; though the engine would still rev, no power reached the tires. No dashboard warning lights illuminated prior to the drivetrain failure, though a check engine light did appear after the vehicle became immobile when I was switching through drive modes. Because there was no available highway shoulder or exit to seek safety, and due to the sudden nature of the mechanical failure, emergency vehicles and tow trucks could not safely divert traffic or move the vehicle in time, resulting in a severe rear-end collision that caused a total loss. The vehicle has not yet undergone a mechanical inspection, but it is currently under a 60-day hold for examination by insurance adjusters and legal counsel, and it remains available for a formal teardown upon request.

NHTSA ID

11745764

Incident

May 17, 2026

10 speed transmission failed at 70K miles. Metal found in the torque converter. Manufacturer recommended routine maintenance was performed on transmission. There needs to be a recall on 2020 to 2021 vehicles with the 10 speed transmission due to the reporting of safety issues of the vehicles locking up while driving. I was lucky to feel the issue happening and getting off the road before it was able to lock up on me causing serious injuries. This needs to be addressed and taken seriously before someone loses their life. Best regards, [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11744565

Incident

Jun 8, 2026

The truck started backfiring and shuddering. Took it to the mechanic and with only 112000 miles I am being told it needs a new engine. It is the 6.2l motor.

NHTSA ID

11743395

Incident

Jun 6, 2026

Loud ticking noise and power loss. Transmission shift slips from 2nd to 3rd . Called factory and dealership for check up. Said no problem… Told to Change oil. Did this, NO CHANGE.

NHTSA ID

11743104

Incident

May 2, 2026

When i first purchased the vehicle off the lot a few years back (its a 21, so probably in 22?) Brand new off the lot minimal miles. Within the first few months we started having issues with the power wanting to shift down. We took it in, the dealership found nothing wrong with it and cleared the codes. This happened a few more times. The last 2 times I took it in. They mentioned that there were recalls on it and could possibly be causing the issue. Took care of that (last august- have docs. to prove it as along with what they did and what we stated). Fast forward now 2 months ago (April of 25) and it starts acting up again and wants to downshift, shifting hard, stuttering and not wanting to drive, the same things we have been complaining about since beginning with lights on etc. However, this time we tried to shut it off and give some down time to get back home. After about 10 mins, we went to start the truck to get it home, and it would not start. We had it towed to the dealership. Once they got it, after 2 weeks of waiting we were finally presented with, the starter went out and the wiring box needed to be replaced (this has to be done before they can look into the original problem again) (because without those 2 things fixed, they wont be able to do) it is now June. I took the vehicle home, due to not having funds to fix right away. After doing some research and some digging, it would appear that the issues that we are having with the truck are issues that are already being recalled on this specific truck and model. However, for mine it is not, because I have the 2.7 l turbo and not the 6.8. THere have been numerous complaints about the known issue.(which i found out is the other wiring by the engine that is being chafed which is causing the wires to break and causing the other box and alternator to go and be replaced). If you replace it fries all again. Why is the 2.6 engine problem thats reported not recalled but rest is and it is known. I also see this online

NHTSA ID

11742660

Incident

Aug 8, 2025

Loud ticking noise and power loss. Transmission shift slips from 2ed to 3rd .Recall to factory for check up. Said no problem? Changed oil. They say it was good. It is not.

NHTSA ID

11742567

Incident

Oct 1, 2025

My 2021 Chevrolet Silverado 1500 with the 3.0 diesel is experiencing constant high running engine fan, engine power reduced notification on the dash, fluctuating temperature and is showing a P1098 code indicating the coolant control valve needs replaced. GM has issued a special coverage on this part, which my truck is well withing the parameters for. However, GM tells me the VIN isn't associated with the special coverage. I have spoken with other owners who have the same year / engine vehicle as I do, and GM replaced their part for free under the special coverage. I have not been giving any explanation as to why my vehicle isn't covered even though the bulletin N25250834 clearly states my vehicle and year. I escalated to the GM executive level and have failed to get my coolant control valve replaced. The vehicle reducing engine power is a major safety concern in traffic as well as the obvious over heating issue. GM is blatantly mishandling the situation.

NHTSA ID

11738805

Incident

Apr 1, 2026