2025 GMC Sierra 1500

These are unverified consumer reports filed with NHTSA, shown as submitted.

• 12/26/2025· VISIBILITY/WIPER,LANE DEPARTURE,BACK OVER PREVENTION

  I own a 2025 GMC Sierra 1500. The rearview camera is inoperable at night (image is too dark). Brought vehicle into to purchasing dealer with complaint. After service, I was told that there was nothing they could do to correct the issue. I then contacted GMC customer service. They advised to bring the vehicle to a different dealer and upon completion to contact customer service again. I did as advised and took the vehicle to a second dealership with the same result. As you are aware, this is a violation of federal law and a serious safety issue for small children, pets or any object behind the vehicle in the dark. Based on what I have been able to discover there are many people with this same complaint. GM is not addressing this issue and is as unwilling to assist others as they have been to assist me.

• 12/26/2025· ENGINE

  Vehicle purchased 8/31/2025 October 20, 2025 "reduced acceleration" alert while driving on why up a significant grade with no way to pull off to the side of the road. Speed limitied to 35mph. Stopped by dealership pulled PO6DD code. Appointment made for November 12th. November 12, 2025 routine oil change and service noted "unable to duplicate concern on vehicly, currently no P06DD is present only DTC that was found in history was U1643 Lost communications with transmission control module can bus 2. cleared DTCs and test drove vehicle and is operating normal no issues. unable to duplicate." December 4th, 2025 driving on interstate and "reduced acceleration" alert...pulled into nearest dealer and code "P06DD" pulled. December 5th, 2025 returned to home dealership "Found Code P06DD. As per TSB#25-NA-307, checked the crankshaft end play, found the crankshaft has excessive end play. This is an indication of a worn thrust bearing. As per TSB engine Replacement is required." Vehicle currently has 6,800 miles.

• 12/20/2025· ELECTRICAL SYSTEM,UNKNOWN OR OTHER

  Onstar telecommunications module failed within 5 months of ownership. GPS and in car navigation goes crazy showing incorrect position which is distracting on the infotainmet screen. Been almost 4 weeks with no estimate of part availability from GM.

• 12/11/2025· STEERING

  Heated steering wheel gets so hot it almost burns to touch it. IR Thermometer readings at the 10 and 2 o'clock positions read between 119 and 125 degrees Fahrenheit. Bottom of the steering wheel is 127-130 degrees. Have made an appointment to have the dealer check for issues.

• 12/08/2025· POWER TRAIN,FORWARD COLLISION AVOIDANCE

  The contact owns a 2025 GMC Sierra 1500. The contact stated that while driving 75 MPH with the cruise control activated, the vehicle failed to accelerate as intended while depressing the accelerator pedal, and the vehicle decelerated to 10 MPH. In addition, the vehicle came to an abrupt stop independently. The contact’s upper body almost struck the front windshield. There was no warning light illuminated. The contact stated that shortly afterwards, the vehicle resumed driving normally at 75 MPH; however, the failure reoccurred after a short distance. The vehicle failed to accelerate as intended while depressing the accelerator pedal and abruptly came to a stop. The vehicle then resumed driving normally. No warning lights were illuminated. The contact arrived at the residence, and the vehicle was towed to the dealer. The vehicle remained at the dealer awaiting a diagnostic test. The manufacturer was not made aware of the failure. The approximate failure mileage was 7,800.

• 12/02/2025· ENGINE

  Truck started with a knocking noise in the engine that developed into a grinding noise. Dealer Service Department inspected and did a transmission tear down only to discover the issue is with the excessive play in the crankshaft. At 13K miles, the service department has stated the entire engine needs to be replaced.

• 11/28/2025· POWER TRAIN

  Intermittent shudder at 25-55 mph under light throttle (rumble-strip feel); 5-6 dealer attempts failed due to non-duplication; GMC corporate (case # 82769068] refused escalation. Safety risk: Distracts from road, potential loss of control.TSB 22-NA-182 is a known issue and dealer says they can’t repair without duplication.

• 11/24/2025· UNKNOWN OR OTHER,LANE DEPARTURE

  While driving in bumper-to-bumper traffic, my vehicle suddenly lost all engine power, the accelerator became unresponsive and the dash indicated "press start". There were no warning lights, no messages, and no prior symptoms before the failure occurred. I was in an active traffic lane when this happened, which immediately placed me and others at risk of being rear-ended. After several seconds, and pressing the start button, the vehicle regained power. But the odometer was indicating I was going 30+ mph when I was going less than 10 mph, so I pulled over to the side of the road. The vehicle is also was having issues with the lane keeping assistance was unavailable. This is is a new vehicle purchase directly from the dealer in August 2025, with approximately 4,500 miles at the time of the incident that occurred on, 11/18. The problem has not been reproduced by the dealership, and no diagnostic trouble codes were found. The vehicle has been at the dealer for inspection since 11/20, but I was informed that the issue would need to happen again before they could diagnose it. This type of sudden power loss while driving is a serious safety concern, especially because it occurred without warning and could happen again unpredictably. At this time, the cause it UNKNOWN, but the component or system responsible for the power loss should be inspected. The failure appears to be intermittent and without warning.

• 11/12/2025· ENGINE

  We were traveling when it went into limp mode slowing our speed way down. We got it to a dealership and they determined low oil pressure and metal in the oil. My vehicle only has 1185 miles on it.

• 11/11/2025· POWER TRAIN

  Transmission module went out at 20,989 miles.

• 11/09/2025· ENGINE

  I got 3200 miles on my 2025 gmc 1500 6.2 engine. The engine crash. Knocking. Skund like its going to jump out. Been at dealer in columbus. Since Thursday. No one touch it

• 10/30/2025· VEHICLE SPEED CONTROL

  The contact owns a 2025 GMC Sierra 1500. The contact stated that while tapping the accelerator pedal, the vehicle suddenly accelerated. The contact stated that the tires were squealing. The contact drove over a cement barrier after depressing the accelerator pedal. There were no warning lights illuminated. The local dealer was contacted. The vehicle was not diagnosed or repaired. The manufacturer was contacted but no assistance was provided. The failure mileage was approximately 7,800.

• 10/27/2025· ELECTRICAL SYSTEM,BACK OVER PREVENTION,FORWARD COLLISION AVOIDANCE

  My vehicle is equipped with multiple safety systems offered by general motors. Since purchasing my vehicle new, I have had a persistent and recurring issue related to the vehicle safety system, which is resulted in numerous collision detection and advanced cruise control service is not functioning as designed, creating safety issues for both myself and potentially other motorist on the road. Additionally, the parking sensors are not working as expected, presumably due to the same issue, which has resulted in numerous safety concerns, including the detection of vehicles or objects, which were not present, resulting in the systematic breaking function engaging posing a risk to myself and surrounding motorists. I initially reported the issue to GM on 2/20/2025, when the vehicle had 467 miles on the odometer. Since the issue initially began, I have returned to the GM service department at my local dealer a total of seven (7) times. The local service department has been in contact with GM corporate office related to the issue, however, they have been unable to rectify the issue and continue to send the vehicle back out on the road claiming the issue has been resolved only for it to recur shortly thereafter. I believe that GM providing the safety features in an inoperable state poses great risk to the general public, and the NHTSA should investigate this issue alongside the other active systemic issues GM is currently under investigation of. At this time, it is unknown what is the cause of the issue, multiple parts have been replaced, and the true cause of the issue has been undiagnosed.

• 10/23/2025· ELECTRICAL SYSTEM

  The vehicle will loose all interior audio to include stereo, turn signals, and all other audio safety features for several hours at a time. GMC has done three repairs and still no resolution. Lack on audio impacts the safety of the vehicle. Has happened dozens of times and appears to be larger GM issue that is u resolved. Has occurred at least 20 times since I bought the vehicle 10 months ago.

• 10/16/2025· EXTERIOR LIGHTING

  Backup camera is not usable at night, you cannot see anything on the camera unless it is a brightly it area. This causes safety concern for people and property. Dealer confirmed no issues with the camera and that is how it is. Had to add external light to ensure I could see at night.

• 10/16/2025· ENGINE

  The engine seized and locked up leading to a catastrophic failure of my three month old 2025 GMC Sierra Denali at approximately 3,181 miles. The engine, the 6.2L V8, was listed as a recall engine by GM for model years 2021-2024. My 2025 allegedly "passed inspection" yet had the same catastrophic failure. The vehicle engine made loud noises and it sounded like parts were breaking. The vehicle no longer starts and had to be taken via flatbed to the dealership where I was informed the engine had to be replaced.

• 10/13/2025· POWER TRAIN

  The vehicle has a vibration and stuttering feel during highway driving. Cruise between 70-75 has off and on again vibration is seat, steering wheel, and center console. The issue feels more pronounced between 60-65 and exhibits more of a hum, much like a washing machine drum that is out of balance. I have had the truck at 2 different dealerships and they have insisted it was a whee balance issue. I have also had the truck balanced at Costco. None of these issues have been alleviated with wheel balance. The dealership, where the truck was purchased, refused to test the truck at highway speeds and would only drive it for a short period at speeds up to 55mph. I have also reached out to GMC customer service, and they simply regurgitated what the dealer indicated about balance and testing at 55 mph or less in town. There seems to be a number of TSBs out on this issue. Most related to torque converter issues, but none of the dealers have indicated that my truck is impacted by any of the current TSBs, even though it exhibits all the symptoms. Not sure of the safety replications, but I am disappointed in the fact that the truck has had this issue since around 1,000 miles, and it seems like the dealer service departments are just ignoring it and refusing to do a thorough evaluation of the issue unless a code triggers or until a major failure occurs

• 09/24/2025· ENGINE

  - On 9/23/2025 while driving down the main street, the vehicle unexpectedly shut down (engine stopped running) and would not restart. The vehicle is currently at Elevation GMC (Boone ,NC) waiting to be diagnosed. - Safety was put at risk by the vehicle unexpectedly shutting down in the middle the of rush hour traffic and not being able to be moved. - When it is was towed into the dealership and explained to the service manager what happened; she said "there is a known problem with the gear select lever losing communication with the truck and not knowing what gear it is in". - As of 9/24/2025; dealership has not looked diagnosed what the problem is/was. - There were no prior warning messages before the engine shut down.

• 09/22/2025· ELECTRICAL SYSTEM,STRUCTURE

  --Radio power button inoperative --Radio channel change buttons, to left of steering wheel inoperative (everyday) --Radio volume inoperative -just stops working (sometimes) --Radio “HOME” button, left of radio power button inoperative --Driver door mirror wobbles when above 50 MPH (very distracting when driving) --Driver door hard to close and out of alignment --Dealership is selling the vehicles KNOWING some of the issues are present, but not advising the buyer. My safety is/was at risk due to having to move my hands off the steering wheel to touch the radio display to make any changes while driving. A certified GM service dept confirmed all my issues and could not repair. They quoted a PIT 6408. However, this particular PIT does not address my issues/concerns.

• 09/18/2025· ELECTRICAL SYSTEM,SERVICE BRAKES,ENGINE

  I purchased a 2025 GMC Denali a few months ago. At approximately 7,000 miles, the front brakes failed unexpectedly and were replaced by the dealership. However, by 14,000 miles, I began experiencing brake issues again. Before I could return the vehicle for service, I was driving on the turnpike when the engine suddenly seized without warning. This created an extremely dangerous situation—vehicles behind me nearly collided as I lost power and control. I managed to pull over safely, but the tow truck operator struggled to load the vehicle due to all four wheels locking up and the engine being completely seized. Once the vehicle was inspected at the dealership, I was informed that the engine had failed and would need to be replaced. I am aware of the recurring issues associated with the 6.2L GMC engines and related component failures, and I no longer feel safe driving this vehicle. Given the repeated mechanical failures and the serious safety risks involved, I am formally requesting that GMC initiate a buyback of this vehicle. I believe this situation qualifies under lemon law protections and warranty obligations, and I urge GMC to take immediate action to resolve this matter.

• 09/08/2025· ELECTRICAL SYSTEM

  Power button (to turn on and off) to radios does not work, the "home" button to the left of the radio power button does not work.

• 09/03/2026· ENGINE

  So I spent many months trying to aquire a GMC Sierra Denali and with all the issues with the 20 - 24 6.2 engines we were assured by the dealer that all the issues were resolved with the 2025 6.2 models. So we spent big to aquire an 2025. So I bought one new. My truck had 8000 miles on it with 2 oil changes. So we booked a trip to [XXX] at considerably a large expense and loaded up our Harley's on my light aluminum trailer, less than 3.5k pounds and headed that way from [XXX]. We made it to [XXX] and spent the night. Next morning we were heading to [XXX] and the truck blew up on the XXX. We were pulled over on a very busy hi way and had to get truck and trailer towed back to [XXX]. We were stuck there for 3 days while GMC installed a rebuilt motor in my 83k truck and totally missed our entire vacation. On line it said GMC would cover hotel and 40.00 dollars a day food. I am so disgusted after being reassured that GMC had fixed the 6.2 and putting our life in danger blowing up on a major highway, and afterward GMC only gave us 200. For our inconvenience. Our room alone was more not counting the money lost on out trip accommodations. I am so completely disappointed with this truck that we bought new and spent more than we ever had on a vehicle, and am afraid of ever taking another trip in it. How can GM be allowed to do this to people. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

• 09/02/2026· UNKNOWN OR OTHER

  Safety Complaint – 2025 GMC Sierra 1500 Tailgate While driving our 2025 GMC Sierra 1500 and towing a trailer, the tailgate unexpectedly opened and dropped down while the vehicle was in motion. No one touched the tailgate button, key fob, or any other controls to activate the tailgate. We were unaware that the tailgate had opened. When we made a turn, the trailer contacted the tailgate and crushed/damaged it. This occurred without any intentional activation of the tailgate release. We believe this presents a significant safety concern because an unexpectedly opening tailgate while driving, especially while towing a trailer, could result in property damage, loss of cargo, or a more serious accident. We are requesting that this issue be investigated to determine whether there is a defect with the tailgate latch, release mechanism, or electronic controls on the 2025 GMC Sierra 1500.

• 09/01/2025· ELECTRICAL SYSTEM

  The cameras will work after the vehicle sits for awhile like after it cools down. But once driving or letting the vehicle run awhile the cameras shut down. I think the Video Processor Module gets hot and shuts down. General Motors is looking into this issue

• 09/01/2025· ELECTRICAL SYSTEM,BACK OVER PREVENTION,FORWARD COLLISION AVOIDANCECrash

  I drove into my driveway put vehicle in park put my window shades up and vehicle went into drive and hit my garage.i had no warnings and this was caught on my ring camera.the ring camera caught my headlights lite up on outside edge and lights kept blinking off an on like there was some kind of glitch.my.the vehicle did not brake either.i saved the video. [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

• 08/29/2026· ENGINE

  Engine making noise during a trip took to dealership and they reported engine is bad and needs to be replaced because it would freeze on the road. Vehicle has 7000 miles.

• 08/29/2026· ENGINE

  FROM DEALER ASSESSMENT Concern - CUSTOMER STATES WHEN VEHICLE IS ACCELERATING THERE IS A RATTLE Correction - test drove and was able to duplicate rattle/knocking from the engine. checked oil level and condition verified both are good. checked for bulletins and followed 23-NA-170. compared vehicle noise to noise is video and noise is nearly identical. removed oil filter and inspected for debris, found heavy amounts of metal debris present in the filter. performed crankshaft end play mesasurement and found that the crankshaft end play is way over spec at 1/4 of an inch. recommend replacing the engine assembly per bulletin Parts) 1x ENGINE 2x (S)GASKET $0.00 $0.00 6x (S)BOLT 1x BOLT 1x exhaust pipe connector gaskets both sides $0.00 8x (S)GASKET 1x fuel feed pipes all $0.00 1x (S)SEAL KIT 1x (S)GASKET $0.00 1x (S)SEAL 1x W-(S)RADIATOR $0.00 1x (S)HOSE 1x coolant $0.00 1x oil filter 1x oil $0.00 Approved 2026-08-18 Labor: $0.00 Parts: $0.00 $0.00 $0.00 $0.00 $0.00 $0.00 $0.00 $0.00 Subtotal Line B: $0.00 *Subtotal is before Shop Charge and Taxes

• 08/29/2026· POWER TRAIN,UNKNOWN OR OTHER,ENGINE

  ENGINE STARTED KNOCKING AT 18K MILES AND TOOK TO DEALER AND THEY FOUND METAL IN THE FILTER AND INSTALLED A NEW ENGINE AND ALSO REPLACED THE MIDPLATE GASKET ON THE VALVEBODY DUE TO A HARSH DOWNSHIFT WITHOUT CODES IN THE SYSTEM THIS ENGINE IS GOING ON 2K MILES AND IT SEEMS TO BE FINE NOW BUT THE PROBLEM WITH 6.2 WAS ONLY SUPPOSED TO BE ON THE 21-24 MODELS AND MINE IS A 25 MODEL AND ALREADY HAD A REPLACED AND NOTHING FROM GM WAS SAID TO EXTEND THE WARRANTY ON THIS MODEL AND POWERTRAIN

• 08/28/2026· POWER TRAIN,VEHICLE SPEED CONTROL,ENGINE

  I own a 2025 GMC Sierra 1500 Denali equipped with the 6.2L V8 L87 engine, VIN [XXX]. The vehicle had approximately 35,000 miles when the engine experienced a catastrophic engine failure. Prior to/during the failure, the vehicle experienced abnormal engine noise and a loss of power. Multiple warning/alarm lights appeared on the dashboard, including the Check Engine and Traction Control warning lights. The engine failure resulted in a loss of motive power and made the vehicle unsafe to operate. PHONE# [XXX] The sudden loss of engine power while driving created a serious safety hazard because the vehicle could no longer operate normally in traffic and could potentially cause a crash. I am requesting that NHTSA document and investigate this engine failure as a potential safety defect involving the GM 6.2L L87 engine. I am also requesting that NHTSA determine whether 2025 GMC Sierra 1500 vehicles equipped with this engine should be included in an appropriate safety recall or other corrective action. The vehicle is a 2025 GMC Sierra 1500 Denali with approximately 35,000 miles. The engine failure and warning lights occurred during normal vehicle operation. The vehicle and repair records can be made available for inspection, and I can provide dealer repair orders, diagnostic information, photographs, and other documentation concerning the failure. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

• 08/28/2026· ENGINE

  Confirmed as catastrophic engine failure by dealership. New engine has been ordered.

• 08/27/2026· ELECTRICAL SYSTEM

  I pulled up to a local store and parked. Just as I was getting out I saw smoke coming from the upper seatbelt area of the rear drivers side seat inside the cab. I jumped in back to see if there was a fire. As I was trying to pull out the top cushions of the interior roof, trying to locate a possible fire, the rear driver-side window suddenly "exploded" - broke in a web pattern across the entire window. I then broke out the center of the glass in case a fire started. I could smell a burning scent. The, suddenly the rear passenger-side window exploded in the same web pattern across that entire window. When my wife arrived to pick me up she could also smell the scent of burning wire. After researching the internet for this issue, we found out that this is a known issue. We discovered at least 6 websites describing this exact issue - one being a GM Customer Satisfaction Program #N192265660 dated January 2020. Apparently the component that has been determined to have failed is the rear window defrost (particularly in models with an electronic sliding rear center window) overheats and causes the smoke and the window breakage. After our truck being at the dealership for approximately 1 month while GMAC supposedly researched the issue, we received word today verbally (Aug 27, 2026) that they declare this issue is not a manufacturer's defect, and they will not cover the repairs. We have requested written confirmation and haven't yet received it. Not only do we currently have the original warranty on this vehicle, we also purchased the extended warranty for the vehicle. The vehicle was inspected by the dealership from which we purchased the vehicle and they stated they couldn't find any issue that would create the damages that the vehicle incurred. Prior to the incident there were no warning lamps or symptoms of any problem.

• 08/26/2026· ENGINE

  Engine shut off. It did restart after placing it in park. I did own a 2022 Sierra Denali and the motor failed on that vehicle. I swapped out to the 2025 to get away from what I thought was a problem on that vehicle and now learning this is an inherent problem with the 6.2L motors that include this year. As a consumer, I am very infuriated that the problem has been in place for years and still is today. The DOD system in these motors is also a problem and will eventually rear it's head out of warranty. You can go purchase a DOD delete kit and pay someone to remove and install the kit but at an additional 2500 in expense for parts and labor. This needs to be addressed!

• 08/26/2025· ELECTRICAL SYSTEM,LANE DEPARTURE,FORWARD COLLISION AVOIDANCE

  On August 15th, 2025, I brought my new 2025 GMC Sierra 1500 Denali to Bill Cramer GM Dealership, 2251 W 23rd St, Panama City, FL 32405, due to a complete loss of audio in the cabin. This affected the turn signals, radio, and critical safety alerts, including collision warnings and seatbelt reminders. Given the vehicle's high cost and its status as a new premium model, this malfunction was both disappointing and alarming, particularly due to its implications for safety. This occurs about every third time I drive the vehicle. The dealership retained my vehicle for over a week to diagnose and address the issue. I received an email stating that the service was complete and the truck was ready for pickup. However, upon arrival, a service technician informed me that they could not identify the cause of the audio failure and, consequently, no repairs were made. I was told the dealership would continue consulting with General Motors' corporate engineers to determine the cause and solution.

• 08/24/2026· ENGINE

  The 2025 GMC Sierra 1500 with 18,675 miles and the 6.2 gas engine failed during a road trip. I was on my way from [XXX] to [XXX] on the Interstate when about 7 hours in, just outside [XXX]. I was noticing a lack in power when I pulled out of a rest area. The truck would not accelerate over 60mph. I slowed down and as I was pulling off the side of the interstate, the truck died. There was knocking sound as I started to pull over. I attempted to restart the vehicle; it did not restart. I called roadside assistance and the tow truck to myself and the truck into Edwards Chevrolet Cadillac in [XXX]. They diagnosed the issue as spun or bad bearing in the engine, and it would need replaced. They told me that the last 6.2 engine took 60+ days to receive and they were now on backorder, plus they already had a truck in the shop waiting for one. There were no warning indicators on the console, and all my service has been done at GM dealers. The biggest safety issue was being stuck on the side of the interstate with rushing semi's going by. I was also going to be stuck in [XXX] until a resolution was found. I ended up purchasing a new 2026 GMC Denali Ultimate with the 3.0 diesel. It was the closest package that was on my 2025 and I wanted to stay the same, minus the 6.2 engine. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

• 08/24/2026· VEHICLE SPEED CONTROL,VISIBILITY/WIPER,FORWARD COLLISION AVOIDANCE

  Cruise control activates at speeds between 1-5mph, which frequently happens while turning, parking, or going through a drive-through. The cruise control activates by a toggle on the left spoke of the steering wheel, which can be easily bumped while doing low-speed maneuvers like parking. When bumping the toggle, the cruise indicator shows a set speed of 15-18 mph, and the vehicle surges forward trying to attain that speed. Since this occurs while maneuvering to park, it creates a dangerous situation if anyone is nearby and you are unable to react in time. This is an ongoing problem that can be duplicated at will. Rear backup camera very dark at night it’s unusable.

• 08/24/2025· UNKNOWN OR OTHER,ENGINE

  I’m filing this safety complaint in addition to a previous complaint, 11678151. which occurred on August 1, 2025. On Friday, August 22, 2025, I experienced a 2nd Traction Control alert and engine failure lights on my 2026 Sierra Denali Ultimate truck which again caused the acceleration to drastically decline while driving home from work. Thank God my kids were not in the car with me this time.  I am extremely appalled and confused as I've NEVER experienced this level of substandard operation from a new vehicle. I have informed the leadership team team at Cavender GMC West San Antonio, TX of the situation. The dealerships recommended (2) paths to exit the vehicle: GMC Customer Assistance and dealership trade-in.

• 08/23/2026· SERVICE BRAKES

  On [XXX], while driving my 2025 GMC Sierra 1500, VIN [XXX], near [XXX], California, the vehicle suddenly experienced a severe brake failure while traveling on a public roadway. When I attempted to apply the brake pedal, the vehicle failed to brake normally and I was unable to safely stop the truck using normal braking. I was forced to reduce speed and allow the vehicle to coast until I was able to enter a side road and bring the vehicle to a stop. I was extremely fortunate that traffic conditions were light at the time. A vehicle traveling in front of me, an intersection, pedestrians, or heavier traffic could have resulted in a serious or fatal crash. After stopping the vehicle, I discovered a metal retaining ring/clip on the floor directly underneath the brake pedal area. At approximately the same time, multiple brake system failure and warning indicators illuminated on the instrument panel. I immediately contacted GMC through the vehicle's SOS system and reported the brake failure. The vehicle was subsequently towed and delivered to a GMC dealership/service department for diagnosis and repair. This appears to involve the mechanical separation or detachment of a component associated with the brake pedal assembly. I have retained the metal component, video evidence of the condition and warning lights, towing information, and dealership repair documentation. A sudden loss of braking caused by the separation of a brake pedal component presents an immediate and potentially life-threatening safety risk. I respectfully request that NHTSA investigate this failure and determine whether similar failures have occurred in other 2025 GMC Sierra 1500 vehicles. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

• 08/22/2026· ENGINE

  One evening while driving home from work, the transmission warning light illuminated on my dashboard, indicating that the vehicle would soon stop. The notification specifically stated there was a transmission problem. The following morning, I brought my truck to GMC for service. After running a diagnostic, GMC confirmed an issue with the transmission. A few days later, GMC informed me that they were waiting for a replacement part to arrive. The part did not arrive for almost a month. During this waiting period, I was forced to pay for a rental car. Since my truck was still under warranty, GMC should have covered the cost of the rental car for the weeks my vehicle was awaiting repair.

• 08/21/2026· POWER TRAIN,ENGINE

  On July 25, 2026 when starting my vehicle, it began to shake violently and I receive numerous errors, including a check engine light and displays in the infotainment, indicating there were engine and transmission errors with the vehicle. I received a text message notification and in app notification from GMC indicating that there was a critical error and provided error code P0352. This appears to be an error related to a faulty engine, this is the 6.2L V8, which is known to be problematic by GMC. Had this happened while I was driving on the interstate three minutes later, it could’ve resulted in great bodily harm or death to both myself and the general public around me. GMC was later able to reproduce the issue at the dealer, confirming the faulty equipment on the vehicle with less than 16,000 miles on it. The component was replaced by the dealer, however, the vehicle is available for inspection.

• 08/21/2026· SUSPENSION,ELECTRICAL SYSTEM,EXTERIOR LIGHTING

  The truck when put in parking it still roll forward a little bit. Back up camera can’t not see during night time. Dealership stated they will not solve that problem and tell us to do manually by turn around look back. The suspension really bouncy but the tech stated that is normal. Spoke to other 3rd party tech they said that not normal at all.

• 08/18/2025· ENGINE

  The contact owns a 2025 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle experienced a loss of automotive power. No warning light was illuminated. The vehicle was towed to a local independent mechanic, where it was diagnosed and determined that the engine had seized and needed to be replaced. The local dealer was contacted. The vehicle was not diagnosed or repaired. In addition, the contact related the failure to an unknown recall; however, the VIN was not under recall. The manufacturer was made aware of the failure. The failure mileage was approximately 75,000.

• 08/17/2026· ENGINE

  The engine shuts off while slowing down. It cuts off cleanly and the entire dash lights up and the transmission shifts to neutral. The driver display says to put the truck in park and hit the start button. After you do this the truck runs fine for about 2k-3k miles and does it again. I has done this 5 times within 10k miles. The dealer says nothing is wrong with the truck because the computer doesn't record any codes. This happens regardless of whether the auto stop/start feature is on or off.

• 08/13/2026· POWER TRAIN

  Truck vibrates at speeds from 25-45 mph while maintaining speed

• 08/08/2025· UNKNOWN OR OTHER

  Driving down interstate highway and sunroof “exploded”. Raising glass sunroof up about 2” above the body. Vehicle had 387 miles on it. This occurred at about 6:55 am and outside temperature was about 74 degrees. The rupture was loud and very startling and I exited the interstate pulling over to see what occurred. There was no damage whatsoever to any other body component and no “flying” debris was observed at anytime that could have struck the vehicle. I requested GMC dealer to look at onboard cameras and save video but they seemed dismissive. Had the interior sunroof shade not been closed I would have been showered in glass while driving.

• 08/06/2025· ENGINE AND ENGINE COOLING

  The contact owns a 2025 GMC Sierra 1500. The contact stated that while at a stop light waiting to make a left turn, the vehicle stalled. The vehicle failed to restart. No warning lights were illuminated prior to the failure. The contact stated that the failure was related to NHTSA Campaign Number 25V274000 (Engine and Engine Cooling). The vehicle was towed to the local dealer to be diagnosed, and the contact was informed that the engine had seized. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 21,100.

• 08/06/2025· ELECTRICAL SYSTEM,VISIBILITY/WIPER,BACK OVER PREVENTION

  The backup camera visibility at night is poor, making it very difficult to see behind the vehicle. This poses a potential safety hazard for pedestrians who may be in the path while reversing.

• 08/05/2025· UNKNOWN OR OTHER

  The drivers side grab handle (a pillar trim piece) is cracked through completely at upper bolt mount location, causing the grab handle to be weakened and unable to safely support while using and could pull away from vehicle while in use potentially causing the driver to fall and become injured. I replaced the original with a genuine OEM replacement from the dealership and it cracked in the exact same place. I posted an inquiry to a Facebook group of fellow GMC owners and there were numerous reports of this having to them and having the dealership replace under warranty, only to have the issue occur again. This structural failure seems to happen with or without use of the grab bar.

• 08/04/2025· POWER TRAIN,VEHICLE SPEED CONTROL,UNKNOWN OR OTHER

  I am writing to express my extreme disappointment and serious concern regarding a critical safety failure I experienced with my 2025 GMC Sierra 1500 Denali Unlimited (VIN: [XXX] ), which I purchased brand new in April 2025 from Cavender GMC, San Antonio, TX. On Friday, [XXX], with fewer than 9,000 miles on the vehicle, I was driving on the highway at about 65 MPH, with my minor son in the vehicle when the dash suddenly displayed a Traction Control (TRC) Fault message, followed immediately by "Acceleration is Limited." The truck experienced a severe and unexpected power loss, severely restricting my ability to accelerate or maintain safe highway speeds. I was forced to pull off the road abruptly to avoid a potentially dangerous situation. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

• 07/29/2026· ENGINE

  Engine started making a loud knocking noise and it sounded like the engine was about to throw a rod. Turned engine off and called GM. Vehicle was towed to dealership and it was diagnosed with a thrust bearing failure. My truck only had 14k miles on it. To fix the bearing issue, it will need a new engine. GM does not currently have engines to replace the faulty ones so it has sat at the dealership for 3 weeks with No ETA as to when it will be fixed. This is apparently a common problem in the 2025-2026 models LZ0 3 liter diesel. They are still selling these affected vehicles currently, knowing that they may have a problem. GM needs to issue a recall and take these vehicles back.

• 07/28/2026· ENGINE

  Going down the highway at highway speeds engine fully seized up almost cause an accident,, totally locked up engine, got towed to dealer and they said total engine failure just like in the priare years., been waiting for a new engine for almost 3month due to these failing on other cars,, they will be replacing my old engine with same engine that in prone to locking up. only a matter of time till the new one does the same thing. i want a buy back but they say it has 70k miles and its over the warranty and they wont buy back