2021 GMC Sierra 1500 complaints

The Intermediate speed sensor 2 and internal transmission harness failed. The repair was to replace the internal transmission harness and intermediate speed sensor. This vehicle is a 2021 and I was told this was recalled on a 2022 only.

Faulty lifters replaced on passenger side. Had only 25000 miles on engine. GM extended warranty on thousands with this engine but not mine. Have only 28000 miles on truck and just turned 5th year so warranty is void. GM should extend warranty on all vehicles with this engine.

TRAVELING ON INTERSTATE GOING AT THE POSTED SPEED LIMIT AND TURNED OFF THE INTERSTATE ONTO MY EXIT TURN AND VEHICLE ENGINE STARTED KNOCKING AND ENGINE SHUT OFF OIL WARNING LIGHT CAME ON ALL WHILE TRYING TO STOP THE VEHICLE AT THE CROSS TRAFFICE STOP SIGHN AND ENDED UP STOPPED IN THE MIDDLE OF ANOTHER HIGHWAY BARLEY MISSING THE CROSS TRAFFIC COMING AT ME FROM BOTH DIRECTIONS. THIS HAPPENED AT I94 AND COUNTY HIGHWAY 34 AT BARNESVILLE MINNESOTA EXIT. THIS SUDDEN ENGINE FAILURE NEARLY KILLED ME AND THE 2 VEHICLE DRIVERS THAT NEARLY STRUCK MY TRUCK FROM BOTH DIRECTIONS. GMC WOULD NOT HELP ME WITH MY REPAIR OF OVER $11000.00 DOLLARS FOR A NEW CRATE MOTOR FROM GMC. SITING MY TRUCK DID NOT FALL UNDER THE L87 RECALL. FAILURE ROD BEARINGS AND CRANK BEARINGS WITH A TON METAL SHAVINGS IN THE OIL AND FILTER. NO WARNING THIS WAS GOING TO HAPPEN. MY TRUCK HAD 95000 MILES ON IT WHEN IT NEARLY KILLED ME AND OTHERS. INDEPENDENT SERVICE CENTER JOHNSONS AUTO REPAIR IN MOORHEAD MN INSTALLED THE NEW CRATE MOTOR FROM LUTHER GMC FARGO ND.

Complete engine power loss.

The contact owns a 2021 GMC Sierra 1500. The contact stated that after the vehicle was taken to a local car wash, upon further inspection, the tailgate door had independently unlatched and was open. No warning light was illuminated. In addition, the contact stated that while driving at an undisclosed speed, the local Police Department called about luggage found on the side of the road. Upon further inspection, the contact noticed that the tailgate had independently unlatched and was open. The vehicle was previously taken to a local dealer, where the vehicle was repaired under warranty. The vehicle was taken back to the same local dealer where it was repaired for a tailgate switch failure at the owner's expense. The manufacturer was made aware of the failure. The failure mileage was approximately 30,000.

Transmission valvebody failure, causing rapid, repeated rear wheel lock ups. Videos can be provided. These happen almost daily at highway speeds. This will cause a very bad accident

The coolant control valve has failed on two occasions—once during the warranty period and again approximately 18 months later, outside of warranty. Each failure resulted in continuous fan operation and fluctuating engine temperatures. Failed on around June 2024 and again December 17, 2025

The power steering on the truck would quit working at times. I made an appointment with a local dealership to have it checked out. I was told the steering rack was binding and would need to be replaced. I was also told there was a two to four week backorder on the parts. As I am trying to back out of my garage to take it to the dealer the steering totally locked up. I called a wrecker to take the truck to the dealer the next day. When the wrecker operator started to load the truck, at first the steering wheel wouldn't turn . Then it broke lose and worked fine. Imagine if I were driving when this on again off again power steering would quit working!! I should also say this truck only has fifty-seven thousand miles on it. Since there is a backorder on these parts it tells me that I'm not the only one that is having this problem. In my opinion this is a very dangerous safety problem and should be a national recall. Thank you

Mechanical and electrical issues with my GMC Sierra Elevation Duramax Diesel, purchased in 2021. Despite multiple dealership visits, diagnostic evaluations, repairs, and software updates, these issues persist and have significantly impacted the reliability and safety of the vehicle. In December 2025, my vehicle was taken to the dealership for diagnostics and a third software update intended to resolve recurring engine-related faults. Throughout 2025, the check engine light illuminated on approximately 30 occasions, confirmed by at-home diagnostic scans. The same diagnostic code related to the 1) SCR NOx Catalyst Efficiency Below Threshold Bank 1 Catalyst 2 P2C7A - Engine I 2) Exhaust Gas Recirculation (EGR) Cooler Efficiency Below Threshold P14D9 - Engine has appeared repeatedly since the vehicle was first purchased in 2021. Additionally, on approximately 15 occasions in 2025, the vehicle failed to start. When pressing the ignition button, the engine screeched while attempting to turn over for 20 to 45 seconds, after which the vehicle powered off entirely. After waiting approximately 10 minutes, the vehicle would then start normally. Notably, during these no-start events, no check engine light or diagnostic code appeared, and the engine light and starting failure have never occurred simultaneously. hese same concerns were explicitly explained to service technicians during the most recent recall repair in 2025. I was informed that a software update would resolve the issue. How

Had a "Trans Hot Warning" light. Dealership said it was internal valve body failure. They said there is recall on this for other engine types even though this is same issue. I think GMC needs to expand their recall.

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the engine seized. The contact was unaware of a warning light being illuminated. The contact stated that while attempting to start the vehicle, the vehicle failed to start. 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 vehicle was not repaired. The contact referenced an unknown engine recall; however, the VIN was not under recall. The manufacturer was made aware of the failure, and a case was filed. The contact was advised to report the failure to the NHTSA Hotline. In addition, the contact was informed that the VIN for the vehicle was a Canadian VIN, and the mileage was displayed in kilometers. The failure mileage was approximately 120,000.

The contact owns a 2021 GMC Sierra 1500. The contact had received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling). The vehicle was taken to the dealer where an inspection was performed on the engine. The contact was informed that the vehicle had passed the inspection, and the mechanic added a higher viscosity oil, installed an oil fill cap, replaced the oil filter, and updated the Owner's Manual. The contact stated that the remedy failed to address or repair the possible defect with the engine. The contact stated that the remedy resulted in a higher cost for oil changes, and fuel economy had decreased from 21 miles per gallon to 18 miles per gallon. The manufacturer was made aware of the issue and the contact was provided a case number. The contact stated that the vehicle had not been repaired. The failure mileage was unknown.

Vehicle experiences a failure to the Lane Departure Warning and Intellibeam headlamps functions, primarily at night. Trouble first began on 3/12/2023 and has been to two GM dealerships for 11 repairs and the problem is still unresolved. GM Executive Escalations have been opened and the problem is still unresolved. Their response is that 18 vehicles experienced this problem and the resolution was to clean the front windshield and update the camera software. This truck has had the camera replaced and software updated three times by two different dealerships. GM is now stating they are unwilling to resolve the problem any further and they would no longer send any Field Engineers to investigate the problem. I have numerous photos, videos and repair logs from with the problem and resolutions performed. Nature of problem: At night, the indicator button for selecting the Lane Departure Warning will go out. If the button is depressed, a message in the DIC indicates Lane Departure Warning Unavailable and there is no way to activate the LDW. It also causes the Intellibeam headlamps to not work. Any help you can provide is greatly appreciated.

Experience a automatic OTA update to the info system on my 2021 GMC Sierra(I did not iniciate) which burnt out the radio module which controls the info system. I am being charged $1,300+ for repair due to vehicle being out of warranty(52,000 miles) and no recall on this vehicle model for this issue. GMC does have a recall for this exact issue on the 2021 GMC Tahoe models, but not the GMC Sierra. If the GMC utilizes the same componets for both models of vehicle how doe the recall#N202319250 not cover the exact same issue on both models?

Heard a ticking noise then check engine light started blinking along with service esc and parking brake. Took it to the dealer and I had a bad lifter again. I was previously repair for lifters under warranty a little over 2 years ago.

On 10/21/2025 as I was traveling on the highway in Kansas at 60 mph, the vehicle lost power and the engine went into limp mode immediately reducing the speed dramatically. Multiple warning lights flashed on the screen. I was able to get the truck to the side of the highway. The vehicle never started again. I was informed by the dealer that the vehicle would need a new engine.

The engine is knocking and running rough. I took it to Christian Brothers Automotive in Newnan Ga and the advised engine replacement.

I purchased a 2021 GMC Sierra 1500 Denali (VIN: [XXX] ) from J.C. Lewis Ford in Pooler, Georgia. The dealership did not disclose an active federal safety recall (NHTSA Campaign Number: 24V-xxx / GM XXX) related to engine connecting rod and crankshaft defects that can result in sudden engine failure and loss of propulsion. The Blue Certified delivery document they had me sign includes a section requiring disclosure of any open recalls, but they left the recall section blank and checked that all recalls were explained to me. No disclosure of any recall occurred during the sale. The vehicle developed engine problems within days and is currently in GMC service. The nondisclosure put me at risk of driving a vehicle with a known safety defect. I am reporting this as a dealer nondisclosure of a federal safety recall. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact's grandson owns a 2021 GMC Sierra 1500. The contact stated that after the vehicle was purchased from a private seller and driven 258 miles, while his grandson was merging off the exit ramp, the engine seized. The low oil pressure warning light was illuminated. The contact stated that the check engine warning light was illuminated prior to the failure. The vehicle was towed to the contact's residence. The contact scanned the vehicle and retrieved DTCs: P0011, P0016, P006DD, and P0521, stored DTCs: P06DD P0011, and permanent DTCs: P0011 and P0016. The engine was replaced by the contact. The local dealer was contacted for parts. No further information was available. The manufacturer was not contacted. The failure mileage was approximately 100,148.

I just surpassed my extended warranty (5 year/100,000 miles) by a couple of thousand miles and my coolant control valve has gone out. The problem is so common that the part is on back order for months at a time. GM says that they issued special coverage for 2020-2022 models, but my dealer is telling me that my VIN is not covered. They want to charge me $2,400 to replace it. This is insane. It’s a very common problem that they know about and it’s going to almost break me. We need help!

ENGINE BURNING OIL AND BLOWING WHITE SMOKE OUT TAIL PIPES. HAVE TO ADD OIL EVERY 1500 MILES OR SOONER IF TOWING. HAS BEEN AN ISSUE SINCE FIRST OIL CHANGE. VEHICLE IS NOW AT 88057 MILES

The contact owns a 2021 GMC Sierra 1500. The contact received the recall letter for NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling). The contact called the local dealer, who confirmed there was no information from the manufacturer to move forward. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The contact had not experienced a failure.

While traveling to work at 75mph, a sudden an unexpected malfunction of internal engine components caused a loss of propulsion.

I was traveling home from work and lost all power to the vehicle while driving. No warning lights, check engine lights came on. I was able to cross traffic and park it in a business place. I had it towed to a chevy dealership for diagnostic. They said that the timing chain came off and i would need a new engine. I had it towed to a auto mechanic shop for a second opinion and they gave the same result. The vehicle is only 4 years old with 92,000 miles on it. When i lost all power to the vehicle, I did not hear any strange noises.

I am an active U.S. Air Force member. My 2021 GMC Sierra 1500 failed GM Recall N252494003 on Sept 29, 2025 (L87 engine loss of propulsion). GM states this defect can cause sudden engine failure and loss of propulsion, increasing crash risk. Despite the confirmed failure, Ocean Cadillac (Miami, FL) told me to keep driving the unsafe vehicle and refused all Courtesy Transportation. The Service Manager admitted in writing that the engine failed, the defect can cause loss of propulsion, and the replacement engine is delayed under GM National Control for up to 3 months — yet they still denied me a loaner or rental. His statements contradict the GM documents he attached: • GM Bulletin DCS7222 says Courtesy Transportation CAN be provided during L87 recall downtime and dealers MUST consider loaners/rentals. • GM FAQ N252494002 says Courtesy Transportation IS available for this recall. • GM FAQ lists recall symptoms (check engine light, hesitation, high RPM, reduced power) — NOT battery drain. • GM states: “If the engine fails, the vehicle WILL lose propulsion.” Ocean Cadillac ignored these rules and put me back on the road in a known unsafe vehicle. As an American manufacturer, GM has a responsibility to protect American drivers. Their failure to follow recall procedures placed me, my family, and other motorists at risk. I request NHTSA investigate whether GM/Ocean Cadillac are complying with recall safety requirements and whether customers are being told to drive unsafe vehicles aft

I was driving on the freeway and my gmc Sierra at4 received a notification that I could could no longer accelerate. I pulled off to the side as safely as I could in a slanted hill in a major freeway with no shoulder. I sat on the side of the road for 45 min and then ran out of diesel gas waiting for the tow truck. We took into gmc and they said nothing was wrong, we were out of gas. But I ran out of gas waiting for the tow truck. The truck never shut off and ac still going, I just couldn’t accelerate. We’ve had the truck in the shop every single month for the past year for sensor issues and replacements and have all the documentation of the last few years of similar issues. No extensions of warranty’s nothing. Well we started to smell something burning this week and now we were told today we have a faulty fuel pump that will cost us $1,000 to fix and is not covered under our warranty. The truck is still under warranty, so why is something in relation to the power train not covered? There is a current t recall on other gmc models of this year for this fuel pump issue and the safety recall is EXACTLY what happened to us on the freeway and the issue we have now. Why has this not been extended to other GMCs????? My entire family could have died on the side of the freeway!!

Took the vehicle to the dealer because of an engine noise. It had issues with the valves knocking when it had around 1000 miles. I took it in and now the truck has around 67,000 miles and I’m being told it needs a new engine because of a bent rod in the engine. I was told that I need a new engine. Previously I had a lot of other issues with the front wheel hubs clicking. But, this truck didn’t even make it to 5 years and now it needs an engine.

I own this 21 GMC Sierra with a 6.2L. This vin is not part of your current recall. But my truck is at a dealership waiting on a replacement engine. I was told that the engine locked up in the bay. Not sure if any lights came on before the engine failed, the dealer did not go into that much of detail. The truck is sitting outside waiting on the engine, not sure if gm made then do any failure analysis or just said its a 6.2 were sending an engine.

My wife was driving at highway speeds with all are kids when the trucks motor suddenly loss all power all check engine lights illuminated and what I'm assuming had major engine failure causing rod knock.

On [XXX], at approximately 15,873 miles and while on the freeway approximately 30 miles from my home, my GMC Sierra 1500 with the L84 engine experienced a failure of the DFM lifter assembly. This required a significant engine disassembly and the replacement of multiple valvetrain components. This repair was performed at Gold Rush Chevrolet in Auburn, CA, as documented in the enclosed service invoice. GM has issued Technical Service Bulletins and product communications addressing similar lifter failures in Gen V small-block V8 engines with DFM/AFM, including Service Update N212353840, PIP5776, #19-NA-219, and related updates. Industry coverage and owner reports and current Class Action Lawsuits indicate that these failures can recur, even after initial repairs, due to the high cycling frequency of the DFM lifters. Given the nature of the defect and GM’s documented acknowledgement of the issue, I am requesting that GM extend the powertrain warranty coverage for the engine and related valvetrain components for a period of 10 years,100,000 miles as a goodwill policy adjustment. A warranty extension would ensure customer confidence and protect against the significant cost of a repeat failure. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V27400 (Engine and Engine Cooling). The vehicle was taken to the dealer, where the contact was informed that the vehicle failed an inspection. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. In addition, the contact was advised that parts were not yet available. The contact was advised that it was unsafe to release the vehicle to the contact with the recall unrepaired. The contact was advised that the repair would take two weeks for completion. The contact stated that the vehicle had been at the dealer for more than two months. The manufacturer was made aware of the issue but provided no assistance. The contact stated that he needed the vehicle to use. The contact was advised that the vehicle was number 1,000 on the list for the repair. The failure mileage was 71,000.

After having transmission issues which was replaced under warranty, within 300 miles, the engine failed. The vehicle has now been sitting at the dealership since October 7, 2025 waiting for a replacement engine. There is no timeline available for the replacement engine as they are currently backordered. Absolutely ridiculous.

I just took my 2021 GMC Sierra 1503.0 Duramax diesel into Faulkner Nissan, today 10/18/2025 m, to have that recall fixed. I picked it up from the dealership and drove about 10 miles before it went into limp mode and reduced power mode while I was driving and started to shift very roughly and I’ve never had any issue like this before they supposedly fix this recall, I think the software patch made it worse in my case. Now my vehicle is throwing a bunch of different transmission error codes, that it has never produced , and it is going into reduced power mode,as I’m driving and going into limp mode as I’m driving, which you never has done before And it feels like it’s stuttering in early gears now and the idle was really rough it didn’t idle at a specific spot it went from 800 to 1300 back down to 800 when it should’ve just been idle at 800. I don’t know what to do. It seems like this recall made the problem worse for me and my truck in this case, I don’t know what to do and I don’t know where to go. I hope you guys can help us. Please make GMC take responsibility Before somebody gets killed. If they haven’t already this issue is extremely DANGEROUS AND I’M SURE IS DESTROYING THE TRANSMISSION. I don’t feel comfortable driving my family in my vehicle anymore because of this issue it is terrifying….

I was driving at highway speeds probably doing 55 and another vehicle pulled out in front of me forcing me to slow down rapidly. That’s when my wheels locked up and my vehicles wheels locked up in the middle of the highway. Screeching tires, almost like the vehicle went into park for a second. After about two seconds, I was able to continue driving a highway speed no check engine lights no error codes. It felt like I just hit something nearly gave me a heart attack. My family was in the car. It felt like we all almost died. It was terrifying. This transmission issue recall situation has happened to me more times than I can count. Now it’s almost a guarantee that if you have to shift too hard too fast it locks up the differential and it is terrifying. Every time.

This was the first time I had ever experienced the rear differential locking up at highway speeds in my truck. It was probably the day after I bought the truck. I was going down route one southbound going probably around 60 miles an hour and the wheels locked up and the vehicle felt like it was gonna come to a screeching hole. It felt like I hit something And then the wheels unlocked and it allowed me to keep driving. I thought that I might have hit the cruise control button on the steering wheel by accident and chopped it up to operator error which now I know is one of the most dangerous recall issues I’ve ever had to experience or indoor. Thank goodness my family was not with me at the time. But these issues continued on for months…

The retractable running board on the driver side retracted well my 3-year-old daughter was climbing into the back of the truck. She then fell off and to the ground. On more than one occasion, I was standing on the retractable running board on the driver side. I was buckling my daughter up in her car seat. The running board retracted in without me doing anything. I did not touch the door and had the driver's side driver door and passenger door open at the same time. This has also happened when just the passenger door was open. The running board retracts and knocks my shins into the truck body. This is quite dangerous and could easily cause great harm. I am not the only one with this issue and have read numerous complaints in online forums. I came across a potential remediation of the problem in an online forum. That remediation included disconnecting the rear toes switch that moves the running board towards the back of the truck, allowing a person to easily reach items that have slid all the way to the front of the bed. Since I disconnected that I have not had a problem with the driver side running board. The passenger side running board is not exhibiting this behavior. For clarity, the running boards are the factory installed running boards, not an aftermarket running board. Please get GM to fix this blatantly obvious safety concern. Thank you very much.

DTC CODE P1098 PRESENT RELATED TO FAULTY COOLANT CONTROL VALVE ON 3.0 DURAMAX DIESEL ENGIINE. THIS IS A KNOWN ISSUE WITH THIS ENGINE AND IS SUPPOSED TO BE COVERED UNDER THE 100K MILE POWERTRAIN WARRANTY. PREVIOUSLY TOOK VEHICLE INTO DEALERSHIP FOR REPAIR INVOLVING REPLACEMENT OF THE COOLANT CONTROL VALVE BUT WAS TOLD REPROGRAMMING OF THE ECM WAS REQUIRED FIRST STEP PER GM REPAIR BULLETIN. REPROGRAMMING COST ME $195 AND WAS TOLD THIS WAS NOT COVERED UNDER THE 100K POWERTRAIN WARRANTY. NOW, A FEW MONTHS LATER, THE SAME ISSUE AND DTC CODE P1098 HAPPENED AGAIN WHILE DRIVING ON FREEWAY AT FREEWAY SPEEDS AND CAUSED VEHICLE COMPUTER TO LIMIT SPEED OF THE VEHICLE WHICH CAUSED HAZARDOUS SITUATION IN CONSTRUCTION ZONE AS WAS NOT ABLE TO MAINTAIN SPEED OF TRAFFIC WHILE TOWING TRAILER WITH BOAT. I ALSO UNDERSTAND THAT GM HAS ISSUED SPECIAL EXTENDED WARRANTY RELATED TO THIS COOLANT CONTROL VALVE IN SEPTEMBER 2025 WHICH EXTENDS THE WARRANTY COVERAGE UP TO 15 YEARS AND/OR UP TO 150K MILES BUT I WAS TOLD AT THE DEALERSHIP THAT MY VIN# DOES NOT QUALIFY FOR THIS EXTENDED COVERAGE FOR SOME UNKNOWN REASON?

Vehicle showing signs of a failing coolant flow control valve and/orcoolant temperature sensor. - AC takes a long time to cool down - Engine fan will stay on after the vehicle is shut off - I often see the notice of “A/C Off Due To High Engine Temp” From what I can find, this issue I’m experiencing is a known point of failure in this vehicle make/model/year. On 10/10/2025, I took the vehicle to Fountain Buick GMC Service in Orlando, FL. The service manager recognized the symptoms immediately, and even knew right away that the part to fix it was on back order - further bolstering that it is an issue that GM is aware of and deals with regularly. Per the service manager, GM’s initial response was to issue a “pay to play” software update that is covered under the 3yr/36,000 warranty, but not the 5yr/100K. Out of warranty, this “solution” costs $499.99, and has a < 10% degree of success. If the update doesn’t fix the issue, then it would be covered. However, the need for the software update was not communicated to consumers. Regardless, since the issue is not yet severe enough to be recognized via code (despite symptoms, pictures, and video), GM will not take any action under warranty towards fixing it at this time. The vehicle’s 5yr/100K warranty expires on 10/15/2025. If the code throws on 10/16/2025, it will not be covered under warranty, but *may* be covered under dealer assistance. And regardless, the $499.99 charge will apply, independent of warranty coverage. More important

Transmission on my vehicle has failed three times since I bought the vehicle in October of 2021. Vehicle currently has 39,000 miles. First transmission issue was resolved by the dealership by replacing the transmission valve body. This solved the problem for approximately 12,000 miles. In September of 2025 with 39,000 miles the transmission suffered a catastrophic breakdown which lead to complete transmission replacement. After being “fix” the vehicle suffered another catastrophic transmission failure within 400 miles of the complete transmission replacement. This incident caused the vehicle to shut completely down and I was stuck in the traffic lane of the US Highway. Fortunately my vehicle and I were not struck while waiting 30 minutes for a tow truck. Presently the vehicle is back at the dealership awaiting repair. From my review of available on-line information it appears there are 10’’s of thousands of GMC Sierra pickups with major transmission issues. This needed to be addressed before someone is killed due to the poor quality of these GMC trucks.

The contact owns a 2021 GMC Sierra 1500. While the contact's husband was driving at an undisclosed speed, the contact noticed an abnormally bumpy ride. The contact felt as if the vehicle was driving over rocks. The check engine warning light was illuminated. The vehicle was taken to the dealer where it was diagnosed with engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, parts were not yet available for the recall repair. In addition, the contact stated that the vehicle had been at the dealer for more than two months awaiting parts. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 80,000.

I took my truck through a car wash and then parked at my parents house. While the vehicle was parked, the trunk latch kept releasing. The trunk popped open. I left it open but you could hear the latch continually releasing and the lights blinking. This went on for an hour and I was unable to drive home because my trunk kept unlatching! A recall was released for other Sierras but not mine. Please investigate my vin and others that may be affected.

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 45-50 MPH, the engine revved and the transmission unintendedly downshifted, causing the vehicle to decelerate unexpectedly. The transmission then seized, and the vehicle skidded. No warning light was illuminated. The vehicle was towed to the dealer, who determined that the transmission had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 127,000.

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign number: 24V797000 (POWER TRAIN), and the dealer performed an interim repair on the vehicle. In March 2025 the part was available, and the recall repair was completed. The contact stated that on one occasion, while driving at an undisclosed speed and then coming to a complete stop, the vehicle jerked and the transmission unexpectedly downshifted. The message “Low Power Mode” was displayed on the instrument panel. The vehicle then failed to accelerate as intended while depressing the accelerator pedal. The contact drove to a parking lot and turned off the vehicle. The vehicle was towed to Don Moore Chevrolet GMC, where it was diagnosed with transmission control valve failure. The contact was informed it would be months before the repair could be performed. The vehicle was towed to another dealer, where the transmission control valve failure was confirmed, and the contact was informed there were metal shavings found inside the transmission. The vehicle remained at the dealer unrepaired. The manufacturer was made aware of the failure. The failure mileage was approximately 115,000.

Constant engine issues, cams, lifters. Transmission problems. These engines in these vehicles need to be RECALLED. I have bought 6 of these trucks and all of them have the same issues. SPENDING 14k on new engines one after another is ridiculous. These are classified as “work” trucks and can’t handle “working”

Transmission failure at a little over 120,000 miles while towing a side by side on the highway. This highway has a speed limit of 80 which is dangerous when the vehicle stops working properly for myself and any other drivers in itself. Earlier this year the transmission had been updated due to a recall and was deemed to work good by the dealership but didn’t notice any difference. Had an engine light pop up a couple hours before but no messages or any other signs to inform me of the issue and was still working fine with no struggle until it gave out

Torque Converter failure confirmed by dealer: was driving at high way speeds when I noticed a slipping sensation from the transmission upon any sort of acceleration. No warning lights were illuminated or any symptoms leading up to the failure. This could have potentially caused me to lose any form of acceleration that would enable me to get off of the highway or away from a situation requiring sudden acceleration.

The 2021 GMC Sierra 1500 has an Electronic Parking Brake (EPB) that bolts on to the rear calipers. The EPB does not release, in order for service, you have to long press the parking brake, then the truck goes into service mode & will release the brakes for service, some newer models may not have this feature. The vehicle has 36,000 miles on it & the inside rear brake rotors are worn down from the EPB dragging & not releasing as supposed to, causing excessive premature wear & that could cause a safety hazard fleet wide. The EPB should not be in use while the vehicle is moving, but it is coded to not release, meaning whenever you press the brake it never moves back out away from the rotor, causing drag & or even can cause warping of the rotor. I do not understand the thought process in regards to not letting the EPB release, it acts like the screw type caliper that would have the same issues of every time it moves out it will not go in until taken apart & screwed in, again meaning the brake pad is constantly dragging on the rotor which could in turn also affect the miles per gallon. I see the thought process to use EPB as useful but not a good execution by the manufacturer.

I have contacted local GMC repair facility (Frank Brown in Lubbock Tx.) about the safety recall on my 6.2 liter engine to attempt to schedule an inspection of my engine and cannot get them to inspect the engine which the recall notice said they would do. They continue to stall and say the inspection isn't approved by GM. I've tried 3 different times to address this isuue without satisfactory results. I recieved the GM safety recall N252494000 notice for my vehicle in May 2025

The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The contact then received a notice that parts for the recall were available. The vehicle was taken to the dealer, and the contact was informed that the recall remedy was for the dealer to use a higher viscosity oil. The contact expressed concerns that the remedy was not a sufficient repair and that the engine was still vulnerable to failure. The vehicle was repaired under the recall. The manufacturer was not made aware of the failure. The contact had not experienced a failure.

Engine lifters bent a pushrod and scratched my camshaft in my engine causing me to be stranded with minor children. 3rd time since I bought this in 2021 that I have had engine faults in this truck.