2021 GMC Sierra 1500 complaints

My power steering completely failed. This is a safety issue and could have caused bodily harm. I have looked on line and I am not the only one with this issue, and as I investigated it shows that this issue was recall situation on earlier models. My truck is currently in the shop and looks like it will cost $5,000 to do the full repair.

I am experiencing a recurring issue with my 2021 GMC Sierra where the dashboard displays a “Shift to Park” warning even though the vehicle is already in Park. This typically occurs when I attempt to shut off the vehicle. The doors unlock as expected, confirming the truck is in Park, but the warning prevents me from turning off the ignition immediately. After a few seconds, the warning usually disappears, allowing me to shut off the truck. This issue is more frequent in cold weather, suggesting a temperature-sensitive electrical or mechanical fault. Based on research and community reports, this appears to be a known issue across multiple GM vehicles, often linked to a faulty micro switch or wiring harness in the shifter assembly. I am concerned about the safety implications, especially if the vehicle fails to shut off properly or if the issue worsens over time. GM has not issued a recall for this problem, and I believe it warrants further investigation due to its widespread nature and potential risk.

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle inadvertently lost motive power. The contact was able to pull over to the shoulder of the roadway, where the vehicle failed to restart. No warning lights were illuminated. The vehicle was not taken to the dealer or an independent mechanic. The vehicle was not repaired. After investigating the failure, the contact related the failure to NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); the VIN was included, but parts were not yet available. The manufacturer was not notified of the failure. The failure mileage was 60,000.

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 15 MPH, the vehicle briefly jerked and jolted, prompting him to discontinue driving the vehicle. The vehicle returned to normal functionality, but the failure became a regular occurrence. The check engine warning light was illuminated. The vehicle was taken to the dealer, who diagnosed failures with the output shaft speed sensor and the transmission control module. The vehicle was not repaired. The manufacturer was notified of the failure but provided no assistance. The failure mileage was 89,000.

See attached document for complaint. I am writing as the owner of a 2021 GMC Sierra 1500 equipped with the 6.2-liter engine that has recently been included in a significant recall. I've been advised that the engine may need to be replaced entirely. As you can imagine, this is extremely concerning given the scale of the defect and the vital role this truck plays i'n my dayto- day responsibilities.

See attached document for complaint.

See attached document for complaint. This law firm represents [XXX] . [XXX] owns a GMC truck with VIN: xxxxxx which is subject to the above referenced recall. Please accept this letter as Mr. [XXX] 's written complaint due to his dealer's failure to remedy the defect covered under the above referenced recall. 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: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure.

Complete engine failure on July 17, 2025, related to current recall for defective engine parts on 6.2L V8 L87 engine. Towed to dealer same day. Dealer continues to report no ETA available on replacement engine. Dealer has had possession of my unrepaired truck for 46 days now and counting.

Coolant control valve failure. Instantly reduces power on truck. National back order on parts. No remedy.

Have owned my 2021 GMC Sierra 1500 with the 3.0 Duramax for a year and the check engine light has come on multiple times for a "Coolant Control Valve" issue. The truck runs the fans at 100% and puts the truck into reduced power at least once a day. I have read that GM sometimes will not cover this repair under powertrain warranty even though it's an engine problem. Please fix this issue! To answer the previous questions, the coolant control valve is malfunctioning, and the truck is currently at the dealer being inspected. Yes the dealer has said this issue is common on these trucks (confirmed by National GMC in American Fork, Utah). Yes the check engine light has appeared multiple times. These issues started appearing in June 2025

I receivd a recall on my 2021 GMC Denali 1500 , 6.2 engine Recall # N252494000. made an appointment with Carroll GMC, at 1455S. Tamiami Trail, Venice , Fl, on 7/29/25 at 11AM. I showed up for my appointment and they denied checking my truck on the recall stating they did not have the remedy to fix the problem so therefore they were not going to check my truck for the recall...... I have a trip coming up and now I a afraid to go on the highway in case my truck loses power and I get in an accident............ MY truck should have been checked for the recall regardless of the remedy to fix it..So at least I know weather it is safe to drive or not

The contact owns a 2021 GMC Sierra 1500. The contact stated that the engine was previously replaced under warranty. The contact stated that the vehicle had been experiencing excessive oil consumption and required three quarts of oil every 30 days. 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 stated that while driving 70 MPH, the vehicle shuddered abnormally and there was an abnormal metallic sound coming from the engine before the vehicle lost motive power. There was no warning light illuminated. The contact was able to pull over to the side of the road. The vehicle failed to restart and was towed to the residence. The local dealer was contacted and informed the contact that a service advisor would return the call. The vehicle was not diagnosed or repaired. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was not made aware of the failure. The failure mileage was approximately 129,000.

The contact owns a 2021 GMC Sierra 1500. The contact stated that while the vehicle was parked, the tailgate opened independently. No warning lights were illuminated. The contact stated that on a separate occasion, while the vehicle was parked at the residence, the contact approached the vehicle and the tailgate attempted to open independently. The contact moved the vehicle and turned off the engine. The tailgate attempted to open independently again. The contact moved the key fob away from the vehicle to prevent the tailgate from opening. No warning lights were illuminated. Most recently, the vehicle was parked at the residence in front of a toolbox, when the tailgate opened independently and dented the tailgate. The contact called the dealer; however, the vehicle was not diagnosed or repaired. Upon further investigation, the contact related the failure to Manufacturer Recall Number: N232426400. The manufacturer was not notified of the failure. The failure mileage was approximately 90,300.

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 local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure.

This vehicle experienced catastrophic engine failure while I was on vacation 400 miles from home. I have researched this failure and there is a class action lawsuit against GMC. My truck has been at the dealer for 25 days and still waiting for authorization from Fidelity Warranty Services. Considering it’s such a common problem I feel GMC should be paying for this. At the very least the warranty company is aware of this problem and purposely delaying the authorization to repair. I just bought a new camper which I cannot use. I am fisherman and cannot use my boat. My beach pass is also on the vehicle. So essentially my summer has been ruined by a company that produced a faulty vehicle and didn’t discord this information to me.

⸻ Background: •2021 GMC Sierra Denali – 6.2L V8 •VIN included in GM’s engine defect recall (connecting rod/crankshaft) •Recall status shows “No current remedy available” •Defect acknowledged by GM can cause “engine damage, loss of propulsion, or complete engine failure.” Timeline of Events: •~1 month ago – Truck began running rough with noticeable ticking/knocking noise. •Dealer could not schedule appointment for 3 weeks. •08/08/2025 – Dealer inspection confirmed failed lifters and damaged camshaft. •Repair estimate: $9,300 (see attached dealer estimate). Connection to Recall: •Lifter and camshaft are internal engine components dependent on the same lubrication and oiling system as the crankshaft/connecting rods cited in the recall defect. •The defect’s potential to contaminate oil and cause internal engine damage makes this failure consistent with recall-related damage.

This recall has been coming for some time now its out and GM still has no plan or action. This is our only auto and my understanding if this issue happens it could cause loss of life. I am concerned for my wife driving to work every day and what happens if we want to take a trip. We need resolution on this. Apr 24,2025 Manufacturer Recall NumberN252494000 NHTSA Recall Number25V274 Recall StatusRecall Incomplete, remedy not yet available [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

2021 GMC Sierra 1500 [XXX] miles 36,500. My childs seatbelt does not work and the lane keep assist does not work 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: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The contact stated that the check engine warning light was illuminated. The vehicle was taken to the dealer, where it was diagnosed with engine failure. The dealer informed the contact that there was no anticipated date for the recall repair parts availability. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 137,000.

What component or system failed or malfunctioned, and is it available for inspection upon request? The Coolant Control Valve has stopped working. How was your safety or the safety of others put at risk? While driving the truck can overheat very quickly which can lead to dangerous temperatures as well as cause me to make an emergency stop on the highway to allow the truck to cool down. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes, I have discussed with a dealership in person and independent mechanic who have confirmed the issue and confirmed it is a very common issue. So common that the only replacement part for the problem is backordered. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? No, they confirmed the issue without inspecting the vehicle because of how common it happens. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? There were no warnings before the issue. The issue happened and then the check engine light turned on as well as a "reduced engine power" message.

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 local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was not made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts not available.

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 stated that while driving 30 MPH, there was an abnormal knocking sound coming from the engine compartment, and the vehicle lost motive power. The contact was able to pull over to the side of the roadway. No warning light was illuminated. The vehicle was towed to a dealer, where it was determined that the engine needed to be replaced. The vehicle was repaired. The contact stated that prior to the engine failure, the transmission was replaced. The dealer was contacted regarding the recall remedy, but the dealer was unable to provide an estimated time of availability. The contact stated that the manufacturer exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the failure. The failure mileage was approximately 20,000. VIN tool confirms parts not available.

Fuel tank leaking.

Coolant Control Valve is faulty. Part number 24001355 for my GMC Diesel Sierra 1500. The check engine light goes on and sometimes the engine power will be cut in half to protect the engine. It can be inspected when needed. My truck cannot go as fast and the Engine fans sound very loud to cool down the engine. I was 3 hours away from my house when this happened the first time and I wasn’t sure I would make it home. I had to let the engine cool down for about 6 hours after I pulled off of the highway. This has happened two times so far and happens when the AC is on and sometimes when you use the remote start it won’t start the truck remotely and the check engine light goes on. The problem started in July 2025 with 51,000 miles. The engine control module code is P1098. I have asked my GMC dealership to look at the issue and they have told me that the part is backlogged for at least 2 months and they will not look at my truck until the part is available. I haven’t had any other issues with the engine so far and this was the first time a check engine light has gone on.

My rear electric window is leaking into my back seat area and the ceiling of the truck has water stains. It is coming from the roof and is leaking in 3 different areas. I am afraid I will now have mold in my car and I can’t have my grandchildren in the car to be safe for them. I had it checked at a local GMC dealer and I had to pay for a leak speacialist to verify and they confirmed the window has a leak. The leak started in April 2025 and has slowly gotten worse. The dealership said I will need to replace my back window to fix the issue and gave me an estimate of $1,100 and said my extended warranty will not cover this issue.

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving approximately 40 MPH, the check engine warning light started flashing and the vehicle was shaking with a misfire coming from the engine. Additionally, there was black and greyish smoke coming from the tailpipe. The Roadside Assistance request message was displayed on the instrument cluster. The vehicle was taken to a dealer where it was diagnosed with a misfire. The vehicle was not repaired. The vehicle was taken to the residence, but the failure persisted. The vehicle was taken to an independent mechanic to be diagnosed, and it was determined that the lifter had dropped, and the engine needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was unknown.

The plastic frame of the rear sliding window failed. This has allowed water to enter the cabin, which can cause mold and other health issues. This seems to be a common issue with these trucks. My truck has a certified preowned warranty and GMC said they would only cover part of it. They charged me $400 as a deductible, which there should be no deductible per certified preowned warranty. I feel like GMC needs to put out an official recall.

I own a 2021 GMC Denali with a 6.2L V8 L87 engine and 45,500 miles. I have confirmed the presence of metal shavings in the oil and oil filter, indicating that the engine is beginning to fail. When I took the vehicle to my local dealership, I was informed that there is currently no fix for this issue and was advised to continue driving the vehicle. This poses a serious safety risk—not just to me and my family but also to others on the road. A sudden loss of power could lead to a dangerous accident, and I do not want to be responsible for something preventable that could harm innocent people. My concern is that GM is aware of this engine issue but has instructed me to keep driving the vehicle, despite the known defect. How can GM be allowed to avoid accountability for such a critical safety matter? If a fatal accident were to occur, would the responsibility fall on GM or the NHTSA for failing to act? It’s also troubling that GM continues to profit by selling new vehicles, including the 2025 models, with similar issues, all while neglecting to provide solutions for affected customers like me. I purchased this $80,000 truck in good faith, but now no dealer wants to trade or buy these trucks without me taking a significant financial loss—something GM should be responsible for. As a taxpayer, I find it unacceptable that we bailed out GM in the mid-2000s, yet they continue to disregard accountability for their actions. I urge the NHTSA to take this issue seriously. A specific deadli

The contact owns a 2021 GMC Sierra 1500. The contact stated that there was an abnormal change with the RPM. There were no warning lights illuminated. 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 local dealer was contacted. The dealer received an email from the manufacturer, but the verbiage was incorrect to move forward with the repair. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The failure mileage was approximately 39,000. VIN tool confirms parts not available.

The coolant control valve (Part # 24001355) has failed. Apparently this is the case with many vehicles and GM will not/can not get replacement parts. This should be a recall.

P1098 Code - Coolant Control Valve on/off/on/off.

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle stalled, lost motive power, with smoke came from the engine compartment. There was no warning light illuminated. The vehicle was towed to the residence. The contact attempted to start the vehicle and noticed a knocking sound coming from the engine with the check engine warning light illuminated. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling). The dealer was contacted and informed the contact that parts were not yet available. The dealer informed the contact that the vehicle had a Salvage Title and would not be repaired under the recall. The manufacturer was made aware of the failure, and a case was opened. The failure mileage was approximately 48,000. VIN tool confirms parts not available.

AT AROUND 60,000 MILES I HAD EXPERIENCED SHUTTERING AND JERKING IN LOW GEARS AND THE VEHICLE SHOOTS FORWARD WHEN COMING TO A COMPLETE STOP. I WAS ABLE TO TAKE THE VEHICLE IN A SHORT TIME AFTER AND I WAS TOLD BY THE DEALERSHIP THAT IT NEEDED A TRANSMISSION FLUSH. I COMPLETED THE FLUSH AND AFTER A WEEK OR TWO IT STARTED DOING IT AGAIN. I TOOK IT TO A TRANSMISSION SHOP AND THEY ADVISED IT IS THE TRANSMISSION VALVE BODY THAT IS BAD. I BELIEVE THIS STARTED HAPPENING BEFORE MY WARRANTY WAS OUT BUT DUE TO ME BRINGING IT IN AFTER THE MILEAGE THEY WOULD NOT HONOR THE WARRANTY. THIS COULD CAUSE MULTIPLE HAZARDS AT STOPS AND WHILE DRIVING. NO WARNING LAMPS OR MESSAGE HAVE EVER APPEARED.

When I started my truck in the morning I noticed the check engine light came on and my engine fan started running really loudly. I shut my truck off and let it sit for 5 minutes and restarted it in hopes the check engine light would not appear. Unfortunately it did come back on and the engine fan began running really loudly again. I drove the truck to the nearest mechanic and you could feel the truck was trying to counter the problem by forcing me to drive it in a lower speed. After taking it to a shop to get it scanned to see what the code was. The mechanic said it was reading code P1006 three times. He said this coolant system and is why my engine fan was triggered to run really loudly. But the engine was not over heating as all other indicators showed that temps were normal. The mechanic believes it could possibly just be a faulty wire. However after talking to GM he said if it is this coolant part that needs to be replaced, it could take up to months to fix as the part is on national backorder. Doing more research, it appears others have had this same problem and GM even knew shortly after this model was released that this would happen.

The check engine light came on at one point. I took it to figure out why the check engine light was coming on and the scanner indicated that the NOX catalyst was below threshold. I researched it and it is a common issue. The check engine light eventually turned off after a couple of days. About 2 weeks later it came back on. I noticed as i was driving the coolant fans were running at 100% meaning that they were blowing long and hard. So I scanned it and it said that the engine coolant valve was at fault. This is also a common issue with the vehicle, particularly in the 2021 GMC Sierra 1500 3.0 Turbo Diesel. It is a faulty part and it costs thousands of dollars to replace. How can these two issues not be on a national recall by GM? They are too common and very expensive to repair. This issue is so common that now the valve is on a national back order. Meaning the parts may not be available for 30-120 days. The vehicle is not safe to drive with a bad engine coolant valve. I have now a rental car for the past 7 days while my truck sits waiting for a valve to arrive and pay thousands in repair just to drive it again.

Wn a 2021 GMC Sierra 1500 6.2L (VIN: [XXX] ), which is now experiencing a severe misfire, engine ticking, and diagnostic code P318A. I’ve confirmed this issue is related to GM Recall N252494001 for engine connecting rod/crankshaft failure. However, I’ve been told my VIN has not yet been activated for recall repairs, and both the local dealership and GMC support have refused to escalate my case or offer assistance. This is a known safety issue, and I’m now at risk of total engine failure and significant financial loss while waiting for GM to act. 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: 25V274000 (Engine and Engine Cooling). The contact stated that while driving at approximately 50 MPH, there was a loud squeaking sound coming from the front driver’s side of the vehicle before the vehicle lost power. Simultaneously, the check engine warning light started blinking. The vehicle was pulled over to the side of the road and the sound became louder, before becoming a knocking sound. The vehicle was restarted, and the failure persisted. The vehicle was towed to the residence. The vehicle was not diagnosed or repaired, but a dealer stated that there was as recall associated with the VIN; however, parts were not yet available to repair the vehicle. The manufacturer was not notified of the failure. The failure mileage was approximately 128,000. VIN tool confirms parts not available.

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 stated that while the vehicle was stopped, the vehicle idled intermittently. In addition, an abnormal sound was coming from the left side of the engine. The vehicle was not diagnosed or repaired. The local dealer was not contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was not made aware of the issue. The failure mileage was unknown. VIN tool confirms parts not available.

My 2021 GMC Sierra 1500 with L87 engine, covered by recall 25V274. None of my local dealers are inspecting for this recall. This truck is my daily driver and I routinely drive on interstates for my work. GM has been slow to address this major manufacturing defect and has not remedied the problem. My truck is no longer worth what is was previously and is lowering trade in or sale value. I am requesting that GM buy back my vehicle due to ongoing safety risks and loss of value.

Was informed from by GM that my vehicle is involved with a recall an still hasn't been repaired

On Dec 27 I noticed a skip in my engine when I started the truck. I took the truck to Cronic Buick GMC on Jan 6 for an inspection. They reported to me that the engine failed.Seized up. I reported the incident to my extended warranty company Warranty Solutions. They refused to do the repair because I was late for an oil change in 2022. After 3 weeks and no cooperation I contacted GM customer service. I was assigned an agent that help initiate the engine repair . The repair was completed on April 12 (3 months after the failure). I paid $4600 out of pocket for a portion of the engine repair .

What component or system failed or malfunctioned, and is it available for inspection upon request? The valvetrain system failed due to broken rocker arms, which resulted in additional internal engine damage. This failure occurred under normal driving conditions. The affected components have not yet been discarded and are available for inspection upon request.How was your safety or the safety of others put at risk? The failure caused sudden engine misfiring and knocking, reducing engine power while I was operating the vehicle. This significantly compromised acceleration and response time, especially during merging and lane changes, which could have led to an accident. Any unexpected loss of power or engine instability at highway speeds poses a serious risk to myself, passengers, and other motorists.Has the problem been reproduced or confirmed by a dealer or independent service center? Yes. The issue has been diagnosed and confirmed by an independent certified mechanic, who verified the broken rocker arms and resulting engine damage during inspection.Has the vehicle or component been inspected by the manufacturer, police, insurance representatives, or others? The vehicle has not yet been inspected by the manufacturer, police, or insurance representatives. Only a certified independent mechanic has inspected the failure thus far.Were there any warning lamps, messages, or other symptoms of the problem prior to the failure, and when did they first appear? Yes. The check engine ligh

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 stated that while driving at approximately 60 MPH, the check engine warning illuminated and the vehicle stalled. The contact pulled to the side of the road and attempted to restart the vehicle, but the vehicle failed to restart. The vehicle was towed to the residence. The contact stated that the failure had previously occurred several times while driving. An unknown local dealer was contacted and informed the contact that the recall parts were not available. The vehicle was not diagnosed or repaired. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was contacted and a voicemail message was left, but the manufacturer had not returned the contact's call. The failure mileage was approximately 70,000. VIN tool confirms parts not available.

The coolant control valve is faulty and is on national backorder causing months of my truck sitting in the shop. This is not an isolated issue. GM is claiming it is not covered under warranty, but the part design is clearly a serious issue.

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 stated that the vehicle was experiencing rough idling, with the RPM fluctuating while driving. The local dealer was contacted. The vehicle was not diagnosed or repaired. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was not made aware of the issue. The failure mileage was approximately 32,000. VIN tool confirms parts not available.

Replacement part needed is COOLANT CONTROL VALVE according to diagnostics at local GM dealer service department after noting check engine light was on. YES, it is available for inspection. Told unsafe to drive as it would very likely overheat or worse. It has been in the shop for a month (as of June 11, 2025) awaiting a backordered part, which we’re told is a national backorder. No loaner vehicle available and told by service department that they have had another truck in for same problem for several months and that this problem is very common. PLEASE HELP us with getting the part needed!

See attached document for complaint.

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving 75 MPH, the vehicle jerked and downshifted to overdrive. The message "Engine Power Reduced" was displayed on the instrument panel. The driver depressed the accelerator pedal, but the vehicle failed to exceed 4 MPH. The vehicle was taken to the dealer, where it was diagnosed that the valve body failed, which caused the transmission to fail. The vehicle was repaired. While the contact was driving home after the vehicle was picked up, the vehicle jerked and hesitated. The dealer was contacted and informed the contact that if the check engine warning light becomes illuminated the vehicle could be diagnosed. After several days, the check engine warning light illuminated, and the vehicle was taken to the dealer where it was diagnosed that the shutter valve had failed and needed to be replaced. The vehicle was repaired. The contact stated that the failure persisted. The contact received NHTSA Campaign Number: 24V797000 (POWER TRAIN). The vehicle was repaired; however, the failure persisted. The manufacturer was made aware of the failure and offered the contact assistance with the transmission repair. The failure mileage was approximately 119,000.

The coolant control valve on my truck is causing issues. From doing research, this is an ongoing issue with the 3.0 duramax. The part is on nationwide backorder and I cannot drive my vehicle in reduced engine power because the only way I can get to work is by taking the interstate. It is madness that GM has not issued a recall or done anything to rectify this issue. Many GMC owners are paying on vehicles that they are unable to drive which is assanine. This part needs to be readily available due to the NUMEROUS complaints that have already been submitted in regards to this part.