2021 GMC Sierra 1500 complaints

I've been to the dealership a few times due to the truck jerking violently under very light acceleration when its trying to shift gears. also there was a few times that the rear wheels have locked up while driving.

L87 engine failure 4 months after it passed the recall test. Experienced shuddering and rpm fluctuation with the cruise control set. Was thinking torque converter. Got it replaced under warranty and the the issues were still there. A week after new TC the truck was running very rough driving down the road. Check engine light along with a low oil Pressure warning and Lost all engine power going 60mph. Would not re fire. Had to coast to a stop with no headlights on only fog lights. Truck is at dealership now will be needing a new engine. P0016 engine code. The truck was in the shop multiple times for misfire and rpm’s jumping and cruise control turning off on its own.

I am filing a complaint regarding a catastrophic engine failure in my 2021 GMC Sierra 1500 equipped with the 6.2L V8 engine. While driving under normal conditions, the engine suddenly failed without warning and threw a connecting rod, rendering the vehicle inoperable. There were no prior warning signs such as knocking, overheating, oil pressure issues or even a check engine light. The vehicle has been properly maintained, including regular oil changes using manufacturer-recommended 0W-40 oil. This failure created a serious safety concern due to the sudden loss of power while driving, which could have resulted in a dangerous situation, especially at highway speeds or in traffic. I am aware that General Motors has issued a recall and/or is aware of similar failures involving the 6.2L engine in certain 2021 vehicles. However, my vehicle’s build date falls just outside the currently defined recall range, despite experiencing the exact same type of catastrophic failure described in those cases. My build date is 12/20 and the recall was issued for 3/21. Given the similarity of this failure to known issues, I believe this defect extends beyond the currently identified recall population. This raises concerns that additional vehicles, including mine, are at risk of sudden engine failure without warning. I am requesting that National Highway Traffic Safety Administration investigate this issue further and consider expanding the recall to include additional affected vehicles outside the

The DEF tank in my truck is defective and its the second time in the last 14 months it has broke. The part is now back ordered and according to the dealership this is a nationwide issue regarding these specific trucks. I have contacted around 10 dealers in my area and all tell me the same thing that they have multiple trucks waiting on the same issue. I have not had my truck for over 2 months and have no idea when i will be getting it back due to dealership having no idea when the part will be released due to the back order. This seems to a huge issue with these trucks and GM is doing nothing to help resolve it. I've reached out to GM directly and get no assistance and now have made 2 payments on my truck and the dealership refuses to give me a loaner vehicle. i am looking for some help or relief on what to do to go about my issue

When my android auto does not connect, it essentially disables the whole infotainment system which is incredibly distracting and dangerous while driving. I am requesting that this be fixed so that I can still use some of the infotainment system but they are redusing to to do anything to fix the issue. The dealer has advised that they are unable to fix the issue because it is software related but yet the software team is saying it is a dealer issue. Please help me get a resolution to this issue!

The contact owns a 2021 GMC Sierra 1500. The contact stated that on Aug. 14, 2025, the PICO engine test was completed on the vehicle under NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling). The dealer stated that the engine had passed the test, and the engine oil was changed to a higher viscosity oil, and the oil cap, oil filter, and the page in the Owner’s Manual were updated. The contact stated that the vehicle was making abnormal sounds while idling, and the fuel consumption had increased. The dealer was contacted and advised the contact to bring the vehicle back to have the engine test performed again; however, the contact refused. The vehicle was not repaired. The contact stated that the engine test had not been performed on the vehicle and that the vehicle was unsafe. The manufacturer was informed of the failure and informed the contact that the vehicle was repaired. The failure mileage was approximately 44,000.

At roughly 5,000 miles had lifter failure which caused loss of power. That was repaired under warranty. Same issue at 86,000 miles - loss of power. New engine which I had to pay for. Same issue at 126,000 miles. New engine required. Covered under warranty. Side note. New engine will only have balance of warranty from 2nd engine or about 5,000-6,000 miles. first incident Feb 2001, second incident about Nov 2004, third incident Mar 2026.

Loss of power, and knocking from the engine while driving. Check brake system, check srs, check parking brake and check engine light flashing came on at the same time. The problem has been reproduced at a mechanics shop and has been determined that cylinder 6 is dead.

Following the remedy of the engine recall in 2025, the truck started having intermittent electrical issues (i.e. warning lights on dash turn on/off: service 4WD, Loss traction Control, etc) come one while the truck is being driven. If the truck is turned off while the dash warning lights are on, it will NOT Start for about 24 hours. If the warning lights are ignored, eventually they will go off on their own. Additionally, the truck is having "no-start" problems (randomly the truck does not start, then after a few days it starts). A New development, when backing up there is a scraping/squealing sound (possibly universal joint). Truck has been back to the dealership that replaced the engine block for the recall and they have failed to identify any issues as these problems are intermittent. Engine Recall Replacement Invoice (Attached)

Took it to dealer for engine sound said nothing was wrong 4 days later rod bearing went out while driving. Truck no longer able to drive

[XXX] we bought our 2021GMC Sierra 1500 from Dealer with 39842 on it. we drove the truck 2910 miles when we checked the oil it was 2 quarts low at 42752. we added oil at that time and called our local dealer to make appointment . appointment at Bowser route 51 Pleasant Hills PA 15236 They informed us they would have to charge us for an oil change to start an oil consumption test on 10/23/25 miles 43829. 11/24/25 brought back to Dealer they said the oil was full yet i checked it in morning it was1/4 low. 1/7/26 brought back to dealer this time they let our truck sit over night the best way to check it and found it to be 3/4 low with only 1,698 miles driven also the antifreeze reservoir was low also they topped off both. 3/8/26 I Checked it ,its now 1 quart low with 1,097 miles driven milage on truck now is 46,623. Summarize GMC will not even look into why my truck is using oil not once my truck is still under warranty where is the consumer protection. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Driving down the road and engine shut off and would not start back. Had it towed to dealer and it needed a motor replacement. Waited over a month for the shop to finish it. New motor has 3k miles on it and is making noise, transmission is stuttering hard and the air conditioning quit working all around the same time. Had to take the truck back to the dealer after the replacement motor was installed because of a faulty “new” starter.

Transmission Shuttering which was confirmed from from GMC dealership , but refused to do any repairs after confirmation or diagnostic and test driving. Demanded a 220$ fee be paid before releasing my vehicle back. Also gave GMC Bulliten # 25-NA-148 which states the same issues I'm currently having.

Rear tailgate on my 2021 Sierra opens or drops when wet. This seems to only happen in a heavy rain or after a truck wash. This problem has been recognized by the manufacturer and the dealer. There is no warning other than the constant clicking of the electric switch allowing the tailgate to drop. This problem has been recalled on the 3/4 & 1 ton trucks but not the 1/2 ton. The tailgate and switches are the same on all 3. Because my vin# does not show for this recall I had to pay for the replacement

The valve body failed, brought it in to a GMC dealership 3 months ago they told me the valve body is on back order. Last week they received the new valve body installed it and tried to program it. While programming it, the brand new valve body failed. So now I am stuck again with no ETA of when a new valve body will be sent to the dealership to fix the issue. this is obviously an issue with the make and model and in my opinion should be a recall. I do not feel safe if I ever get my truck back from this issue due to ongoing valve body failures nation wide and two on my end.

Engine developed a low knock type noise just above idle while beginning to move in the parking lot. It was also noted pulling away from an intersection at low rpm under light acceleration. Oil pressure was normal, 30 psi and approximately 50-60 at cruising speed. Low level knock began earlier in the day but no other symptoms. Oil level was checked and found to be at proper level. At mile 2 into my trip a chirping/ squeak type noise was heard under light throttle and light load at approximately 1500 rpm. The noise stopped when accelerator was released. Rough running sensation followed the noise under the load. Noise returned when the accelerator was pressed and then the engine stopped running while traveling 45-50 mph. Placed the shifter to neutral and attempted to restart, engine rolled slowly for a brief moment and then locked up entirely. Starter only clicks when attempted after that. Vehicle left me stranded with no heat on the shoulder of the highway in the dark in Northern Michigan on March 5, ambient temp was 28 degrees. Vehicle towed to closest dealership which is also where it was purchased for inspection on 3/6/2026. General motors customer care contacted and case opened. No assistance with repair at time of callback.

With the cruise set at 55-60 mph the Rpms will jump, along with a slight shudder feeling. Cruise control has turned off a few times due to this. Cruise set at 25mph and would shudder/lunge forward. Torque converter is showing it’s slipping and will need replaced. No check engine lights.

Per GMC dealership, this vehicle suffered a Transmission valve body failure and they are recommending replacement of the entire transmission.

My vehicles transmission is part of a recall but my vin is not registered for this recall repair. Please assist.

Engine coolant control valve failure. This is a widespread issue on 2020-2022 3.0L Diesel trucks and it hasn’t been addressed by GM, leaving owners to pay out of pocket for a faulty part.

Vehicle began to slip or shift hard when putting it in gear or coming to a stop. The next morning the vehicle would not move when put in drive or reverse.

I was driving on a highway on my way home from work. Thank god there was not a lot of traffic because my truck just shut off lost all power, then I received a message on the dash to put on neutral and restart. I tried multiple times to turn it back on. It never turned on and had to get it towed to nearest dealership. It took them a week to inform that the engine locked up even though I tried to take it for the recall they told me to wait and reschedule the appointment. Never got a new appointment until the engine failed and I got it towed to the dealership and have also not received a new kind of loaner from GM. This will be my last GMC truck I purchase.

The contact owns a 2021 GMC Sierra 1500. The contact stated that while operating the vehicle, the check engine warning light illuminated and remained illuminated. While driving at various speeds, the vehicle entered LIMP Mode, causing the vehicle to decelerate. Additionally, the radiator fan was continually activated while operating the vehicle. The vehicle was taken to the local dealer, who diagnosed that the coolant control valve was inoperative and needed to be replaced. The vehicle was not yet repaired. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 119,000.

The failed component is the engine coolant control valve on a 3.0L Duramax truck. The failure has been documented and confirmed by both an independent mechanic and an authorized dealership. The malfunction creates a significant safety hazard. Without warning, the truck will suddenly enter a reduced engine power mode while traveling at normal highway speeds. When this occurs, the vehicle will not allow acceleration beyond approximately 50 miles per hour. This is especially dangerous when operating on roadways with speed limits of 70+ mph, as the sudden and unexpected loss of power places myself and surrounding motorists at risk. The problem has been reproduced and confirmed by Steele GMC in Round Rock, Texas. In addition, the vehicle has been inspected by an independent mechanic, both of whom verified the coolant control valve failure. Prior to the initial occurrence of the failure, there were no warning signs. Once the malfunction occurred, the check engine light illuminated. General Motors has issued Service Bulletin #25-NA-185 (revised December 4, 2025), which addresses engine coolant control valve failures on 3.0L Duramax vehicles and outlines the proper diagnostic and repair procedures for this exact failure mode. This bulletin applies to 2021–2026 3.0L Duramax trucks. Additionally, GM has implemented Special Coverage program N252508341 for 3.0L Duramax coolant control valve failures, which extends coverage up to 15 years or 150,000 miles when diagnostics confirm the fail

I have had shuddering on the highway and a few hard random diwnshifts. Last week I went to start my truck and the transmission started grinding and rattling. I was told after towing to the dealer it needed a transmission due to pump not getting enough fluid and had failed. I was told I needed to pay, even though the part causing the problem had a extended 150,000 miles and the subsequent pump failure is a result of the control valve failure.

Had a P1098 code. The truck was diagnosed by a certified technician. Found to have a failing coolant control valve. GM has issued special coverage for this known failure. Special coverage is not including the VIN for this truck although it falls in the criteria for model, year, and engine model.

Engine failure without any warning. Car maintenance was kept up-to-date.

The engine has been burning oil since purchased but really highlighted when at 47k miles I got a dashboard message saying “reducing power to engine” I checked the oil and it didn’t register in dipstick. I added 3quarts of oil to show up on dipstick. When I changed the oil which I did at my own garage only 2.5qrt came out including what was in filter. It’s since take an average of 2.5qrt between oil change at 7500. Also the transmission is slipping which happened after warranty expired at about 69k miles and I don’t want it to repair or repair until gm fixes these issues which they know are problem in2020-2021 models but they haven’t addressed it. My truck has been serviced at the dealership except fo 3 oil changes. The issue are noted but the answer is car burn oil typically between changes. Yeah they do if it was 20yrs old not 3yrs. The issue lies with GM. It’s Needs to be addressed.

At 22,000 miles I experienced issues while driving on a 150 mile trip. We frequently take this particular drive. We choose to driver later in the evening to miss commuter traffic. This even we pull over for a late dinner and hear a loud ticking noise while the the truck seems to lose power. I turn the vehicle off and start it again and its worse, it barely idols and shuts down. I'm in a parking lot and drive down the block to a gas station where serves only gas and no mechanics onsite. I turn off the car and wait 5 mins and restart, same results but this time all the warning lights come on. We end up finding a hotel and in the morning i find a Chevrolet dealership down the block, I ask if I can take it in, there the advisor connects to my obd port and says there are many issues and needs to see a mechanic. I manage to get it towed 80's to the original dealership. Advisor says the engine is bad and replaces it. Now my vehicle has 38,000 miles and I run into the same issue, loud ticking sounds and low power. Immediately I drive it home and the next day have it towed to the dealership to have it looked at. The advisor said during their analysis they saw metal in the air filter so another engine has to ordered and installed.

Loss of power code p0016 now truck won't start

Burns excessive amounts of oil between oil changes.All cars were covered under the g.M recall mine fell, one month behind.But this motor is the exact motor that has been recalled to put in a heavier weight oil.Please expand the recall.So my truck can go in.

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving 65 MPH, the vehicle was shaking abnormally with the check engine warning light illuminated. The contact pulled over to the side of the road and had the vehicle towed to the residence. The contact referenced NHTSA Campaign Number: 25V274000) (ENGINE AND ENGINE COOLING) as a possible cause for the failure. A dealer was not contacted. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was 66,456.

4 months after bring my truck back to the dealership for a body valve issue on the 10 speed transmission. The truck went into limp mode while I was driving.

The oil consumption is abnormal and burns almost 2.5 to 3 quarts between oil changes. This can be a heavy risk to the engine if I don’t check on it every couple weeks. I don’t think after the price I’ve paid for this truck that I should have this concern and this should not be the case

My 6.2 engine locked up and left me stranded. Had it replaced with s new engine on 10/31/2025 and I'm having problems again with it. As well as my 10 speed transmission slipping and hunting for gears

On the afternoon of 01/20/26, I was merging onto the highway in my 2021 GMC Sierra 1500 when a loud bang was heard from the engine compartment at approximately 60 mph. Immediately after the ban was heard, several indicator lights on the dashboard were illuminated, including the ESC, check engine light, and parking brake light. A power loss was felt when attempting to accelerate and the banging noise worsened anytime the accelerator was depressed. I was able to drive the vehicle to the nearest GM dealership that coincidentally was at the closest exit off of the highway I was traveling on. The dealership performed diagnostic and determined that the damage was caused due to the ongoing GM recall associated with Safety Recall N252494000. My vehicle had previously been inspected as part of the recall and was found to have passed. Vehicle had been driven approximately 4,000 miles after recall was performed.

There is an active recall for the 6.2 L engines, which is what I have and it’s an issue with burning oil and catastrophic engine failure due to rods and bearings. And I just got this vehicle in November and I have already went through 15 quarts of oil in two months so I’m waiting for my engine to blow up going down the road to cause a wreck like has happened to multiple vehicles already and I also have a rod knock now due to this issue so it could be any time now that my engine fails and I end up getting hurt or my family I took it to the Chevy dealership and I have called GM to do an oil consumption test and to put in a claim so that way if it does fail, then it has paperwork to follow, but it is a major safety concern but something needs to be done considering there’s already 600,000 recalls on this issue already there needs to be more for the rest of the people that are having this issue like myself and I’m spending $50,000 on this truck for the engines to fail and me end up dying before something‘s done. and it’s also very distracting as you’re driving down the road and your vehicle tells you that you’re low on all so you have to try to find a way to get off the highway to have someone bring you all so you can continue to drive and it’s not just a cordial. It is up to 5 quarts of all at a time.

For the second time since I have owned the vehicle that was purchased brand new. The engine seized during driving on the highway and began making loud noises that was knocking and jerking the vehicle. The issue occurred initially around 15,000 miles and was diagnosed as lifter failure, was repaired and returned in July 2022. At 64,000 miles on January 15, 2026, while on an interstate the engine did the same thing and the vehicle went into limp mode. It has been diagnosed as lifter failure this second time and is awaiting appropriate repairs. Both incidents put myself in passengers at danger due to the nature in which the vehicle entered limp mode on the highway.

1-At approximately 40,000 miles, my transmission was replaced under warranty. It had been failing since approximately 2000 miles having a very hard time shifting between first and second gear. It was finally replaced at 40,000 miles. 2- At approximately 45,000 miles I took my truck into the dealership for this latest recall on the 6.2 L failure for inspection. Vehicle is inspected and I was told I would need to have an engine replacement. I was told that there was no ETA on when a replacement engine would be available and that I would be contacted when one was. Afterwards I was sent back home in the truck they just inspected for potential engine failure and said had a bad engine. As of now, I’m still waiting on a word of a new engine and my truck is still operating, but leaves me concerned that it could fail at any moment while driving it.

The engine has a knocking sound. I took it into the dealer and they replaced the exhaust system thinking that was the problem. However, the knocking still happens intermittently. I have video documentation of the noise.

Truck went in service 9/17/2025 because the wheels locked up while driving. Transmission was replaced. Picked up truck and 2 hours later the truck shut off while driving and was started back up and was limp mode. Was told wire chaffing and they taped and rerouted wires. Picked truck back up and next day it did the same thing. Took back to the dealer and they said wires again. They taped wires back up and we picked up the truck. We had it 7 days and while driving down the expressway the whole truck shut off and would not start up again. Clearly that is a safety issue. After sitting on the side of the expressway for 10 minutes it started up again and was in limp mode and taken to the dealer again. I don’t know what has been done to it yet as they are not great at communication but they have had our truck for 4 months minus the 7 days we had it before it had to go back to the dealer.

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 5 MPH, the vehicle lost proper steering ability, and the steering wheel became loose and spun around in a circle. The air bag message was later displayed on the instrument panel. Upon inspecting the vehicle, the contact discovered that the bolt connecting the steering shaft was missing. Due to the failure, the vehicle was towed to a dealer, where the cause of the failure was confirmed. The contact was then informed that there were no recalls or warranties on the vehicle. The manufacturer was notified several times about the failure and agreed that the part should never fail. However, the manufacturer then stated that the owner of the vehicle was responsible for the repair. The vehicle remained with the dealer unrepaired. The failure mileage was approximately 80,000.

The front camera stopped working, causing the safety systems to shut off. Codes U026A & U0078 "no communication failure". The camera was ordered and replaced.

Left rear parking brake actuator malfunction. The truck would brake unexpectedly. The brake would not completely release at times. Took it to the dealer on June 6, 2024 and they replaced the rear rotors and pads. I asked them if the parking brake actuator was faulty and may have caused the premature wear. They laughed and said no, it wasn't possible. On Aug 7, 2024 I returned the truck to the dealer with the fault codes C1114 & C060B caused by a failure of the parking brake actuator. It was impossible to use the emergency brakes when the codes were present. For several months after the repair, brake faults would appear and disappear randomly. Took it to the dealer, and they found nothing wrong. Electric-actuated emergency brakes should be illegal.

Unexpected rear wheel lock-up at 29000 miles. While engine braking from highway speed onto an off-ramp at approximately 50 mph, the rear wheels unexpectedly locked up. Due to prior rear brake actuator issues, I suspected the emergency brake had activated without my input. It was only momentary, and no fault codes or warnings were displayed. It happened again under the same circumstances two months later, with no fault codes. On May 9, 2025, the check engine light came on, and I scheduled service. The dealer addressed a recall regarding the transmission by installing software. In August 2025, I received a letter from GM regarding recall N242454440 for excessive wear in the transmission control valve, which was causing rear-wheel lockup. On October 31, 2025, while towing a small enclosed trailer at 70 mph on the highway with cruise control engaged, the truck suddenly decelerated, and I was nearly rear-ended by a semi-truck (no brake lights to warn them). The truck would not go over 50 mph unless I was going downhill. The transmission would not shift into higher gears. I returned it to the dealer, who checked the computer and found no record of the incident, so they said there was no problem. They informed me that the new software was designed to limit the truck's speed if a potential lockup was detected. This recall did not fix the transmission problem or the safety issue. It was simply a way to avoid costly repairs. There is a problem with the physical transmission valve that,

Muti pro tailgate has electric issues due to moisture. Tailgate will open up driving down the road.

The contact owns a 2021 GMC Sierra 1500. The contact stated that after driving on a trip, the contact noticed that the vehicle had lost 10 MPG after a software update was performed. The check engine warning light was illuminated. The vehicle was taken to Richardson Chevrolet (3825 S Huron Rd, Standish, MI 48658), who confirmed that the vehicle was working as designed. The check engine warning light was reset. The vehicle was not diagnosed or repaired. The manufacturer was contacted and opened a case, and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 57,000.

2021 gmc purchased brand new Truck had complete engine failure lifters and rods were replaced at 7000 miles under factory warranty lost complete engine power GMC says we are not on any recall and they refused to buy back the truck or give me an extended warranty they said this year 2021 with 5.3 doesn’t have engine issues.

I own a 2021 GMC Sierra 1500 equipped with the 6.2L L87 V8 engine and 10-speed transmission. The vehicle exhibits the following issues: Persistent lifter ticking noise audible from the driver-side wheel well, even when the engine is warm. Rough idle that is noticeable at stops and low-speed conditions. Transmission shifting problems, specifically harsh or delayed shifts when downshifting from 3rd to 2nd gear during deceleration. These symptoms raise concerns about potential lifter failure and transmission defects. I am aware of GM’s recall (25V-274) and NHTSA Engineering Analysis EA25007, but my vehicle’s build date (January 2021) currently falls outside the official recall window. Given the similarity of symptoms to those under investigation, I believe my vehicle may be affected by the same defect. Safety Concern: The rough idle and shifting hesitation could lead to unexpected loss of power or unsafe driving conditions, especially during deceleration or merging. Request: Please include this complaint in EA25007 and consider expanding the recall to cover earlier builds. I am willing to provide service records, videos, and additional documentation upon request.

Motor was chugging took to a dealership on march 22 was told I had a collapsed lifter I was told my cost would be 4800 gm would cover half which was fine then when the work was done the dealership took it for a test drive while they were on the test drive the motor locked up they originally told me it was a cam bearing later I found out through paperwork that was emailed to me that it was a main bearing which is consistent with the recall but my vin number hasn’t came up it’s a 2021 gmc sierra 1500 with a l87 6.2 and it cost me 6200 I was 10,000 miles out of warranty