2021 Chevrolet Silverado 2500 problems

POWER TRAIN

My 10L1000 transmission had a catastrophic failure internally which caused it to rough shift, sudden down shifting, not want to shift into gear at all, and high engine rpm prior to roughly shifting. I took it to the Chevy dealers mechanic the very next business day, only to find out that from the mechanic that this is a common occurrence with Chevy transmissions in my truck and google also verified this to be a common problem. The mechanic from the Chevy dealership also stated that there was larger metal chunks than normal. My truck is available for inspection asap. The manufacturer and vin lookup contradicts the mechanic and google stating no issues or recalls for my transmission. After speaking with the manufacturer, I became highly concerned due to their unwillingness to address the obvious issues known by so many. If I wasn’t such a safe driver and immediately brought it to the mechanic, this could have caused a terrible accident leading to extreme bodily harm or death even. According to a quick google search of the 2021 Chevy 2500 transmission problems and my mechanic this is a well known problem even though Chevy manufacturers refuse to acknowledge the issue or implement a recall. There was zero warning lights or lamps to indicate this problem. I am extremely concerned with the manufacturer’s response to my concerns and their unwillingness to correct this issue before it cost someone their life. This catastrophic failure with the transmission having metal shavings throughout it and extreme damage to the transmission valve body and being well known and reported by many other customers has to be addressed. Chevy’s unwillingness to acknowledge people’s claims in this has left me with around $10,000 in monetary damages and could have lead to bodily harm or death if I would have been traveling on a main highway or interstate when it occurred. At the very least Chevy needs to be held responsible for this known and reported issue before it causes death or injury.

NHTSA complaint #11752243 — an unverified report by a vehicle owner.

TIRES

Wrangler Trailrunner AT LT275/65R20 were on the truck when I purchased my new 2021 Chevy 2500. I only have 25K miles on it. I was driving on the interstate and the tread came off the tire tore my wheel base apart and damaged back of truck along with scratches on the side by wheel also tore wheel trim off.

NHTSA complaint #11750813 — an unverified report by a vehicle owner.

LATCHES/LOCKS/LINKAGES

The contact owns a 2021 Chevrolet Silverado 2500. The contact stated that the electronic tailgate door had erroneously opened and closed and also, moments after turning the vehicle off the door had erroneously opened. The cause of the failure was not yet determined. The manufacturer was notified of the failure. The contact was informed that the VIN was not included in the NHTSA Campaign Number: 24V060000(LATCHES/LOCKS/LINKAGES). The contact indicated that the vehicle had experienced that same failure listed in the recall. The failure mileage was 47,000.

NHTSA complaint #11740554 — an unverified report by a vehicle owner.

SERVICE BRAKES

What component or system failed or malfunctioned, and is it available for inspection upon request? - The parking brakes were engaged and would not release / yes, it is available for inspection How was your safety or the safety of others put at risk? I was in traffic stopped at a train track and could not move. Has the problem been reproduced or confirmed by a dealer or independent service center? - Yes, the rear actuator for the brakes was faulty and had to be replaced. The warranty work was completed by the dealership Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? - Unknown Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? - Not prior to the problem My concern is that my parking brakes "were nonexistent" per the dealership when they were diagnosing the warning light. So, I am afraid that the truck was driving while these were engaged.

NHTSA complaint #11728599 — an unverified report by a vehicle owner.

POWER TRAIN

Operator of this vehicle was commuting and truck started to slow down and chug. Vehicle hesitated when operator applied gas pedal. -Transmission cooler inlet/outlet pipe as per Chevrolet known issues. -Safety of driver at risk as failure happened in heavy traffic, unable to pull to safety -Yes confirmed by authorized repair facility -Part inspected by authorized mechanic. -No warnings, symptoms, prior to failure.

NHTSA complaint #11725594 — an unverified report by a vehicle owner.

UNKNOWN OR OTHER

The rear window in my 2021 Silverado 2500 leaks when it rains, water is getting in the carpet/seats creating a bad odor and mold. The dealership will not assist in fixing this known issue.

NHTSA complaint #11724840 — an unverified report by a vehicle owner.

ENGINE

Similar to the issues that were on the gas version of this engine and the recall associated with it. The engine seized on the expressway. When it was towed to the dealership, they said it was catastrophic engine failure. They found a lot metal shavings in the oil pan. They did not diagnose any further due to cost. At the time it happened, there were no warning lights or check engine lights on.

NHTSA complaint #11724650 — an unverified report by a vehicle owner.

POWER TRAIN

While traveling at highway speed on the interstate in my 2021 Chevrolet Silverado 2500 HD (approx. 120,000 miles), the vehicle experienced a sudden hard jolt followed by a momentary rear wheel lockup. This occurred without warning. Immediately after, the transmission defaulted into a fail-safe condition and became locked in 4th gear. The vehicle would move but could not shift properly, resulting in abnormally high RPM and engine load at highway speeds. I was forced to continue driving several miles in this condition to reach a safe exit. The unexpected drivetrain behavior and temporary wheel lockup created a serious safety risk, including potential loss of control and risk of collision. The dealership identified transmission diagnostic trouble codes P2715 and P2733 (pressure control solenoid performance). Transmission fluid was found to be burnt and contaminated with metal debris. The vehicle is subject to GM Special Coverage N242454441 for a known control valve body defect that can cause harsh shifting and reduced engine power. Although code P0747 (referenced in the bulletin) was not present, the failure involved transmission hydraulic pressure control. The dealership is replacing the valve body under the special coverage but is not addressing the internal transmission damage, stating they cannot determine whether the damage resulted from the covered defect. The sudden rear wheel lockup and transmission fail-safe condition at highway speed present a significant safety concern involving unintended drivetrain behavior.

NHTSA complaint #11720857 — an unverified report by a vehicle owner.

POWER TRAIN

The vehicle experienced a sudden and complete transmission failure at approximately 77,800 miles. There was no prior abuse or modification. The failure resulted in loss of normal drivability and required full transmission replacement. The transmission was replaced with a remanufactured unit due to catastrophic internal failure. Repair costs were approximately $7,000. I am aware of similar GM transmission issues and recalls affecting comparable model years and components. Although my VIN is not currently listed under a recall, the failure appears consistent with known GM transmission defect patterns. The failure occurred while the vehicle was in the middle of an intersection in heavy traffic, resulting in sudden loss of vehicle functionality. A child passenger was onboard at the time. The incident created a significant safety hazard due to loss of drivability in an active traffic environment.

NHTSA complaint #11717291 — an unverified report by a vehicle owner.

SERVICE BRAKES

On 01/16/2026, Quirk Chevrolet completed product safety recall N242482680 for the Brake Pressure Switch Connector Fire on my vehicle. Shortly after, my vehicle would come to an abrupt stop on its own while driving. This happened twice on my way home and then the third time at home at which point, it would no longer move forward or backward. The vehicle needed to be towed to the dealership that did the recall. After researching online, I discovered this is a known issue after the recall because the recall component is faulty. One source reports the cause is an improperly manufactured jumper harness which is missing protective tape or a faulty internal C-clip in the cylinder. Another source states the post-service emergency brake issues often stem from a software update meant to enhance safety or an incomplete repair of the brake pressure switch wiring harness. The update automatically engages the parking brake. I absolutely know that the catastrophic failure of my vehicle's braking system was a direct result of the recall work; however, the dealership made me pay for the repairs out of pocket until such time as GM or Chevy makes an "official" recall on the faulty recall. My safety and the safety of others was put at risk by way of my vehicle stopping abruptly on its own. The problem has been reproduced by many sources online - just do an online search "2021 Chevy 5500 emergency brake issue after brake recall completed" and see all the results that come up corroborating my personal experience. Quirks Chevrolet in Manchester, NH inspected the vehicle. No warning lamps or messages appeared on the dash. Please contact me if you want any additional information or copies of receipts, etc. My vehicle is available for inspection upon request.

NHTSA complaint #11716406 — an unverified report by a vehicle owner.

POWER TRAIN

first issue was around April-May 2025 when my engine started knocking and burning fuel. Warning light came on and it went right in to the dealer where I have all my maintenance done. They determined that it due to (2) faulty fuel injectors and I had them replaced at that time. In December of 2025 my engine started doing the same thing as before with the knocking and burning fuel and reduced speeds when on the highway so again it went into the dealer. It has since been in there and first was told it was the fuel injector again. They priced out the one was bad and I asked them to replace the remaining 6 fuel injectors so I didn't have this issue again in the near future. They did and the vehicle had the same issues going on. During the next inspection it was determined that the engine needed new rocker arms. These were replaced but this also did not solve the problem and the vehicle would not pass the regeneration on the engine. During the next inspection it was determined that we needed to replace a cylinder and one of the valves. After this was complete they were still having issues and then I was told that the Piston was bad and there are (2) bad valves so I need an entire engine replacement. My truck only has 130,000 miles and has been in the shop for almost 2 months last year from engine issues and it has had all maintenance completed at he same dealership with Records.

NHTSA complaint #11711815 — an unverified report by a vehicle owner.

ENGINE

first issue was around April-May 2025 when my engine started knocking and burning fuel. Warning light came on and it went right in to the dealer where I have all my maintenance done. They determined that it due to (2) faulty fuel injectors and I had them replaced at that time. In December of 2025 my engine started doing the same thing as before with the knocking and burning fuel and reduced speeds when on the highway so again it went into the dealer. It has since been in there and first was told it was the fuel injector again. They priced out the one was bad and I asked them to replace the remaining 6 fuel injectors so I didn't have this issue again in the near future. They did and the vehicle had the same issues going on. During the next inspection it was determined that the engine needed new rocker arms. These were replaced but this also did not solve the problem and the vehicle would not pass the regeneration on the engine. During the next inspection it was determined that we needed to replace a cylinder and one of the valves. After this was complete they were still having issues and then I was told that the Piston was bad and there are (2) bad valves so I need an entire engine replacement. My truck only has 130,000 miles and has been in the shop for almost 2 months last year from engine issues and it has had all maintenance completed at he same dealership with Records.

NHTSA complaint #11711815 — an unverified report by a vehicle owner.

FUEL/PROPULSION SYSTEM

first issue was around April-May 2025 when my engine started knocking and burning fuel. Warning light came on and it went right in to the dealer where I have all my maintenance done. They determined that it due to (2) faulty fuel injectors and I had them replaced at that time. In December of 2025 my engine started doing the same thing as before with the knocking and burning fuel and reduced speeds when on the highway so again it went into the dealer. It has since been in there and first was told it was the fuel injector again. They priced out the one was bad and I asked them to replace the remaining 6 fuel injectors so I didn't have this issue again in the near future. They did and the vehicle had the same issues going on. During the next inspection it was determined that the engine needed new rocker arms. These were replaced but this also did not solve the problem and the vehicle would not pass the regeneration on the engine. During the next inspection it was determined that we needed to replace a cylinder and one of the valves. After this was complete they were still having issues and then I was told that the Piston was bad and there are (2) bad valves so I need an entire engine replacement. My truck only has 130,000 miles and has been in the shop for almost 2 months last year from engine issues and it has had all maintenance completed at he same dealership with Records.

NHTSA complaint #11711815 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

The contact owns a 2021 Chevrolet Silverado 2500. The contact stated that the connector for the heater system was causing the vehicle to overheat, subsequently enabling the vehicle to go faster than 50 MPH. If the vehicle reaches 75 miles, it would immediately decrease in speed to 5 MPH. The vehicle was taken to a certified mechanic who diagnosed a P20C1 code, indicating reductant heater failure had occurred. The vehicle was not repaired. The contact called the dealer, who recommended calling the NHTSA Hotline to file a safety complaint. The manufacturer was informed of the failure they also referred the contact to the NHTSA Hotline to file a safety complaint. The failure mileage was approximately 68,000.

NHTSA complaint #11704659 — an unverified report by a vehicle owner.

AIR BAGS

Driving about 45 mph and unexpectedly both roof rail air bags deploy stoping vehicle on the road.

NHTSA complaint #11702013 — an unverified report by a vehicle owner.

VEHICLE SPEED CONTROL

I own a 2021 Chevrolet Silverado 2500HD Duramax diesel with approximately 100,300 miles. The truck began displaying a “Service Emissions System” warning and a countdown message that in a certain number of miles the vehicle will be limited in speed (for example to 65 mph). GM’s own Duramax diesel owner’s supplement explains that when a “Service Emission System” message appears it is accompanied by a distance-until-speed-limit countdown and that the truck will progressively limit speed first to about 65 mph and then to about 55 mph if the condition is not corrected, telling the owner to see the dealer. This creates a safety risk because the derate can occur while driving on highways or rural roads, where an unexpected limit on maximum speed can interfere with merging, passing, and keeping up with traffic. This is our only vehicle, and we must use it for important medical appointments, including cardiology and surgery-related visits. The condition started only about 300 miles beyond GM’s 5-year / 100,000-mile powertrain warranty. I opened a case with Chevrolet / GM Corporate (Service Request No. XXX) and took the truck to Sons Chevrolet in Columbus, Georgia on November 17, 2025 for this issue and a rear wheel lockup recall. The dealer kept the truck from about 9:00 a.m. to 3:00 p.m. and indicated they might need to keep it for at least two more days, but I was not given a clear written explanation of the diagnostic trouble codes or a firm repair plan. Because GM’s own manuals describe this “Service Emission System” message together with speed-limit countdowns, and because the vehicle can actively limit speed on the road if the fault is not resolved, I am concerned this represents a broader emissions/derate defect on late-model Silverado HD Duramax trucks. I request that NHTSA review similar complaints and consider whether further investigation or a safety recall is warranted. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11700011 — an unverified report by a vehicle owner.

ENGINE

I own a 2021 Chevrolet Silverado 2500HD Duramax diesel with approximately 100,300 miles. The truck began displaying a “Service Emissions System” warning and a countdown message that in a certain number of miles the vehicle will be limited in speed (for example to 65 mph). GM’s own Duramax diesel owner’s supplement explains that when a “Service Emission System” message appears it is accompanied by a distance-until-speed-limit countdown and that the truck will progressively limit speed first to about 65 mph and then to about 55 mph if the condition is not corrected, telling the owner to see the dealer. This creates a safety risk because the derate can occur while driving on highways or rural roads, where an unexpected limit on maximum speed can interfere with merging, passing, and keeping up with traffic. This is our only vehicle, and we must use it for important medical appointments, including cardiology and surgery-related visits. The condition started only about 300 miles beyond GM’s 5-year / 100,000-mile powertrain warranty. I opened a case with Chevrolet / GM Corporate (Service Request No. XXX) and took the truck to Sons Chevrolet in Columbus, Georgia on November 17, 2025 for this issue and a rear wheel lockup recall. The dealer kept the truck from about 9:00 a.m. to 3:00 p.m. and indicated they might need to keep it for at least two more days, but I was not given a clear written explanation of the diagnostic trouble codes or a firm repair plan. Because GM’s own manuals describe this “Service Emission System” message together with speed-limit countdowns, and because the vehicle can actively limit speed on the road if the fault is not resolved, I am concerned this represents a broader emissions/derate defect on late-model Silverado HD Duramax trucks. I request that NHTSA review similar complaints and consider whether further investigation or a safety recall is warranted. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11700011 — an unverified report by a vehicle owner.

FUEL/PROPULSION SYSTEM

I own a 2021 Chevrolet Silverado 2500HD Duramax diesel with approximately 100,300 miles. The truck began displaying a “Service Emissions System” warning and a countdown message that in a certain number of miles the vehicle will be limited in speed (for example to 65 mph). GM’s own Duramax diesel owner’s supplement explains that when a “Service Emission System” message appears it is accompanied by a distance-until-speed-limit countdown and that the truck will progressively limit speed first to about 65 mph and then to about 55 mph if the condition is not corrected, telling the owner to see the dealer. This creates a safety risk because the derate can occur while driving on highways or rural roads, where an unexpected limit on maximum speed can interfere with merging, passing, and keeping up with traffic. This is our only vehicle, and we must use it for important medical appointments, including cardiology and surgery-related visits. The condition started only about 300 miles beyond GM’s 5-year / 100,000-mile powertrain warranty. I opened a case with Chevrolet / GM Corporate (Service Request No. XXX) and took the truck to Sons Chevrolet in Columbus, Georgia on November 17, 2025 for this issue and a rear wheel lockup recall. The dealer kept the truck from about 9:00 a.m. to 3:00 p.m. and indicated they might need to keep it for at least two more days, but I was not given a clear written explanation of the diagnostic trouble codes or a firm repair plan. Because GM’s own manuals describe this “Service Emission System” message together with speed-limit countdowns, and because the vehicle can actively limit speed on the road if the fault is not resolved, I am concerned this represents a broader emissions/derate defect on late-model Silverado HD Duramax trucks. I request that NHTSA review similar complaints and consider whether further investigation or a safety recall is warranted. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11700011 — an unverified report by a vehicle owner.

SERVICE BRAKES

Took truck to dealer with concern of higher than normal braking force needed. Couldn’t verify concern. Looked today under the steering column and the brake booster is leaking fluid inside the cabin of the truck when the brake pedal goes through the firewall. There was Almost no brake fluid inside the reservoir causing the brakes to fail with no warning. Looked at similar trucks and all have brake fluid leaking from the same location. With as little as 10,000 miles. Mine has 22,000 miles and it’s failed requiring complet replacement of the brake booster. Taking to the dealership to replace the complete brake booster assembly when part is available. This is a 21 Chevy 2500 truck that pulls up to 18,000 pounds. higher than normal braking application needed, can be deadly or lead to complete brake failure whether loaded towing a trailer at a weigh of 25,000lbs or even the 7,000 pounds empty the truck weighs would reasonably result in the loss of someone’s life. Only thing that drew me to this concern was a harder application of the brake pedal and noticing brake fluid under the dashboard. Would gladly allow anyone to inspect my truck.

NHTSA complaint #11699620 — an unverified report by a vehicle owner.

POWER TRAIN

The contact owns a 2021 Chevrolet Silverado 2500. The contact stated that while slowing down and coming to a stop, the accelerator pedal was depressed while in drive; however, the vehicle started to roll backwards. The contact depressed the brake pedal to prevent the vehicle from rolling backwards, and the RPM became elevated to 5,000 RPM. The contact immediately turned off the vehicle to prevent the RPM from continuing to increase. The vehicle was shifted to park, restarted, and then shifted to drive(D) and the brakes released. While releasing the brake pedal, the failure reoccurred. The vehicle was immediately turned off and towed to the residence. The dealer was informed of the failure of the clutch pack, which was welded together from friction. The dealer scheduled an appointment; however, the vehicle was not diagnosed or repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 100,000.

NHTSA complaint #11698898 — an unverified report by a vehicle owner.

VEHICLE SPEED CONTROL

The contact owns a 2021 Chevrolet Silverado 2500. The contact stated that while slowing down and coming to a stop, the accelerator pedal was depressed while in drive; however, the vehicle started to roll backwards. The contact depressed the brake pedal to prevent the vehicle from rolling backwards, and the RPM became elevated to 5,000 RPM. The contact immediately turned off the vehicle to prevent the RPM from continuing to increase. The vehicle was shifted to park, restarted, and then shifted to drive(D) and the brakes released. While releasing the brake pedal, the failure reoccurred. The vehicle was immediately turned off and towed to the residence. The dealer was informed of the failure of the clutch pack, which was welded together from friction. The dealer scheduled an appointment; however, the vehicle was not diagnosed or repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 100,000.

NHTSA complaint #11698898 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2021 Chevrolet Silverado 2500. The contact stated that while slowing down and coming to a stop, the accelerator pedal was depressed while in drive; however, the vehicle started to roll backwards. The contact depressed the brake pedal to prevent the vehicle from rolling backwards, and the RPM became elevated to 5,000 RPM. The contact immediately turned off the vehicle to prevent the RPM from continuing to increase. The vehicle was shifted to park, restarted, and then shifted to drive(D) and the brakes released. While releasing the brake pedal, the failure reoccurred. The vehicle was immediately turned off and towed to the residence. The dealer was informed of the failure of the clutch pack, which was welded together from friction. The dealer scheduled an appointment; however, the vehicle was not diagnosed or repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 100,000.

NHTSA complaint #11698898 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

We believe that it is the park sensor in the column . When you place the truck into park, the screen displays the words shift to park period and the dinger.Inside the truck continues to ding for a long time, even with opening and closing the door ... The truck is actually in park, so it does not move.But the display says it's not.And apparently it is not registering because it keeps dinging

NHTSA complaint #11695209 — an unverified report by a vehicle owner.

UNKNOWN OR OTHER

Unable to remove key from ignition for a period of time ie. 30 sec. to a minute or more. After driving the vehicle for a either a long or short period of time and you park it, you can't turn the ignition lock all the way off.

NHTSA complaint #11688418 — an unverified report by a vehicle owner.