Complaint volume
487 consumer-submitted complaints are matched to this model year. Treat the count as a research signal, then read the actual summaries for repeated symptoms.
Complaint records
2021 GMC Sierra Complaints
487 consumer-submitted complaints on record for the 2021 GMC Sierra, grouped by component category.
487 Total complaints
5 Crash reports
6 Fire reports
2 Injury reports
Complaint data reflects consumer-submitted reports. A complaint is not proof
of a defect, recall, or manufacturer fault. Enriched severity fields come
from official bulk records when the complaint can be matched by ODI number.
Buyer interpretation
How to use these complaints before buying
Complaint records are most useful when they turn into inspection points, seller questions, and comparison checks against nearby model years.
Pattern to inspect
The most common categories are engine, power train, engine and engine cooling. Use those categories as a test-drive checklist instead of judging the vehicle from the total count alone.
Severity flags
Enriched records include 5 crash reports, 6 fire reports, 2 injury reports, and 0 fatality reports. These fields come from complaint records and should be read in context.
Mileage clue
Mileage is available on 104 complaints, with an average reported failure mileage of 51,093 miles. Compare that with the mileage on the listing.
Questions to ask the seller
- Have you had any problems related to engine, power train, engine and engine cooling?
- Can I see recent maintenance and repair records?
- Has the vehicle ever been towed, involved in a crash, or repaired for the same issue twice?
- Can we also check the recall record for this 2021 GMC Sierra?
Used-car checklist
Use these complaints before the test drive.
Build a buyer checklist to turn these issues into questions and inspection points.
2021 GMC Sierra
Build buyer checklist Compare with other years Sends year, make, and model to pre-fill your checklist.
How severe are the 2021 GMC Sierra complaints?
5 Crash
6 Fire
2 Injury
0 Fatality
30 Towed
3 Medical attention
What are the most common 2021 GMC Sierra complaint categories?
ENGINE 156
POWER TRAIN 59
ENGINE AND ENGINE COOLING 37
POWER TRAIN,ENGINE 29
ELECTRICAL SYSTEM 26
UNKNOWN OR OTHER 14
STEERING 13
UNKNOWN OR OTHER,ENGINE 12
ELECTRICAL SYSTEM,ENGINE 9
SERVICE BRAKES 9
487 total complaints on record
Latest complaints
| Date | Component | Summary | Severity | Mileage |
|---|---|---|---|---|
| Oct 2022 | ENGINE | The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle went into Limp Mode with the check engine, DEF tank, and emission warning lights illuminated. The vehicle was taken to the dealer, and the dealer replaced several unknown sensors; however, the failure recurred. The dealer determined that the computer needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 35,000. | Crash: No Fire: No | 35,000 |
| Oct 2022 | STRUCTURE | The contact owns a 2021 GMC Sierra 1500. The contact stated that after parking the vehicle, it was discovered that the electronic multifunction tailgate had erroneously opened. Also, during the failure the tailgate struck a scooter lift that was attached to the vehicle. Both the tailgate and the scooter lift were damaged. The contact indicated that the failure had occurred on multiple occasions. The vehicle was taken to the local dealer who was unable to determine the cause of the failure and the vehicle was not repaired. The manufacturer was also notified of the failure. The contact was concerned that if a heavy load was being carried at the time of the failure it might have fallen onto a busy freeway. The failure mileage was 6,000. | Crash: No Fire: No | 6,000 |
| Sep 2022 | UNKNOWN OR OTHER,VISIBILITY/WIPER | The driver-side mirror on my 2021 GMC sierra is unusable at freeway speed. When traveling at freeway speed the glass moves due to wind and causes the reflection in the mirror to be blurry. The reflection from the mirror is blurry to the point that I'm unable to identify objects in the mirror and it is difficult to gauge size and closing speed of any objects in the mirror. The issue has been with the vehicle since I purchased it new in June of 2021. The issue has been reproduced by two different dealership service centers and the entire driver-side mirror assembly has be replaced twice with the issue persisting. I have videos showing the issue but they are too large of files to upload on this form. | Crash: No Fire: No | Unknown |
| Sep 2022 | STEERING,SERVICE BRAKES | I start my car and I went to pull off and the steering wheel locked up and I couldn’t turn it and it was just stuck going to sit power steering EC something. And then came home parked the car few days later try driving it and then the ABS brake light came on warning me not to go over 65 mph and my brakes pad feel really loose now. | Crash: No Fire: No | Unknown |
| Aug 2022 | BACK OVER PREVENTION | The contact owns a 2021 GMC Sierra 1500. The contact stated that he had received an unknown Manufacturer recall notification related to the Back Over Prevention camera. The vehicle was taken to the dealer and the recall repair was performed. Upon return of the vehicle, the grid pattern on the camera was very dim and was not visible to the contact while in use. The vehicle was taken back to the dealer where he was informed that the recall was performed correctly and that no further repair could be performed. The manufacturer was notified of the failure and a case was filed. The contact was then referred to Bob Clapper Automotive (3601 E Milwaukee St, Janesville, WI 535460) for further assistance. The vehicle was taken to the dealer; however, the dealer offered no further assistance. The dealer provided the same information as the original dealer. The vehicle was not repaired. The failure mileage was 7,000. | Crash: No Fire: No | 7,000 |
| Aug 2022 | STEERING,SUSPENSION,LANE DEPARTURE | I took my truck to the dealership because of my issues and they said they had many trucks going in with the same issue but there was no fix to it. The issues Popping Noise Heard On Hard Turns and/or Going Over Speed Bumps, Creaking Noise While Turning Wheel Left and/or Right, Clicking Noise Heard On Slow Sharp Turns.Also when you go over a bump the truck makes a spring loud noise to the point that the whole truck bounces. shifter is also very hard when you try to change gears. | Crash: No Fire: No | Unknown |
| Aug 2022 | TIRES | The contact owns a 2021 GMC Sierra 1500 equipped with General Tires, Tire Line: Grabber HTS60, Tire Size: 275/60 R20, DOT Number: (NA). The contact stated while driving 15 MPH in a parking lot, the rear passenger’s side sustained a blowout. The contact stated that the low tire pressure warning light was illuminated. The contact was able to park on the side of the road and replaced the rear passenger’s side tire with the spare. The contact took the vehicle to the local dealer to be serviced. The vehicle was not yet repaired. The tire manufacturer had been informed of the failure. The failure mileage was approximately 18,700. | Crash: No Fire: No | 18,700 |
| Jun 2022 | ELECTRICAL SYSTEM | The contact owns a 2021 GMC Sierra 1500. The contact stated while attempting to start the vehicle, the vehicle failed to operate as needed. The service parking brake, check engine, and other unknown warning lights were illuminated. The vehicle was towed to the local dealer to be diagnosed. The contact was informed that the failure was due to damaged electrical wiring caused by rodents. The contact was informed by the dealer that the wiring insulation was made from soy-based materials. The vehicle was repaired three times due to the failure. The manufacturer was notified of the failure. The approximate failure mileage was 23,300. | Crash: No Fire: No Towed | 23,300 |
| Jun 2022 | ENGINE | Engine lifters failure, caused ESC light to come on and check engine light and other dash lights. Lack of power from engine causing dangerous driving in traffic. | Crash: No Fire: No | Unknown |
| Jun 2022 | FORWARD COLLISION AVOIDANCE | When using adaptive cruise the brakes have engaged aggressively without cause. This has happened several times prior to my discontinuing the use of this option. I have not had it in for service yet (we just returned from vacation). | Crash: No Fire: No | Unknown |
| Jun 2022 | POWER TRAIN,ENGINE | 1 June 2022, while driving, started hearing a clicking noise from front end, under hood. Took to local GM dealer, Mechanic drove with me, and he heard the noise, said he would order a part and safe to drive. So, I went home. 2 June 2022 started same vehicle, a very loud banging, clicking, shuttering noise from under hood, I took back to same dealer, Dealer said collapsed valve lifter. GM service notice says for dealer to fix under warranty. Apparently, a known problem with MANY 2021 GMC 5.3 L engines. PLEASE MAKE GM RECALL THIS ISSUE FOR REPAIRDS | Crash: No Fire: No | Unknown |
| May 2022 | SERVICE BRAKES,ELECTRICAL SYSTEM | The contact owns a 2021 GMC Sierra 1500. The contact stated that when pulling a trailer with electric brakes with their vehicle, a warning light stating to check the trailer would illuminate on their instrument panel. The warning light would also state that the electric brakes had disconnected and then reconnected shortly after. The failure would occur on a consistent basis. The main control computer system in the center where the radio is located would flash the message that the trailer brake gain not been recalled. The contact contacted the dealer who confirmed that the computer system was known to have an issue due to the interference between the electric brakes and the LAD lights on the vehicle, however, there was no recall. The vehicle had not been repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 21,000. | Crash: No Fire: No | 21,000 |
| Apr 2022 | ELECTRICAL SYSTEM | The contact owns a 2021 GMC Sierra 1500. The contact stated while using the GPS, the digital speedometer failed to operate as needed. The contact notified the dealer of the failure and the system was rebooted; however, the failure persisted. The manufacturer was made aware of the failure and a case was opened. The approximate failure mileage was 1,000. | Crash: No Fire: No | 1,000 |
| Apr 2022 | STEERING | As I was driving out of the parking lot my power steering suddenly was lost. A message appeared on the screen saying: Service Power Steering Drive with care and an esc message. A light also appeared. I was not able to steer at all and had to turn the truck off. I tried multiple times. After 5 minutes the message cleared as did the light. A day later (today- 4/19)the same thing happened in the parking lot. THIS IS VERY DANGEROUS. I have an appointment with the dealer. When looking up this problem it appears there are multiple recalls on other 2021 models but not the Sierra though I see many complaints about the same problem on the Sierra's. This is not safe and needs to be looked into further. | Crash: No Fire: No | Unknown |
| Apr 2022 | UNKNOWN OR OTHER,ENGINE | My truck shakes/shutters at random times. while steadily driving at constant speed and/ or shakes/shutters even more when I try to accelerate. | Crash: No Fire: No | Unknown |
| Mar 2022 | STEERING | The contact owns a 2021 GMC Sierra 1500. The contact stated while the vehicle was standstill, the steering wheel seized. The contact stated no warning light was illuminated. The contact called the local dealer and made them aware of the failure. The contact was instructed by the dealer, to remove the ground cable from the battery and reinstall. The contact stated he was able to reboot and the steering wheel was able to move properly. The manufacturer had been informed of the failure. The failure mileage was approximately 15,000. | Crash: No Fire: No | 15,000 |
| Feb 2022 | ENGINE | The contact owns a 2021 GMC Sierra 1500. The contact stated that the check engine warning light was illuminated and the vehicle failed to accelerate above 60 MPH. The contact took the vehicle to the dealer who diagnosed that the DEF tank had failed and needed to be replaced. The vehicle had not been repaired. The manufacturer was not made aware of the failure. The approximate failure mileage was 4,000. | Crash: No Fire: No | 4,000 |
| Feb 2022 | ENGINE | The contact owns a 2021 GMC Sierra 1500. The contact stated that after starting the vehicle, the check engine light remained illuminated and the vehicle would not properly accelerate while depressing the accelerator pedal. The vehicle was taken to the local dealer who diagnosed that the engine valve lifter was faulty and needed to be replaced. The vehicle was repaired. The manufacturer was notified of the failure. The approximate failure mileage was 11,000. | Crash: No Fire: No | 11,000 |
| Feb 2022 | ELECTRICAL SYSTEM,ENGINE | While driving, when approaching speed of 40 mph, the engine begins to have dull shutter intermittently as though I am going over pot holes or rumble strips when I am not. Regardless of time or day or weather the truck has performed in this way. I have had it to the dealership twice for the issue. The first time they said they didn’t feel anything and unable to duplicate the problem. The second time, the vehicle was with the dealer for several days trying to determine the other issue it was there for. I requested they again try to recreate the concern. The service assistance asked if I was willing to ride with the technician to see if I could point it out for him. In scheduled a time to do so, when I arrived, the technician was not there. I reside an hour away from the dealership. Making these round trips and getting no where with support or answers. When this happens, I become extremely anxious about the safety of the truck. Also- while 4 X4 is engaged, the truck has significant shutter when going up hill, as though the transmission is going to drop. The entire truck will violently shake. | Crash: No Fire: No | Unknown |
| Feb 2022 | ELECTRICAL SYSTEM | The console radio dash has gone completely black while both driving and while using it for the speaker/phone system. The incident resulted in the entire system restarting. | Crash: No Fire: No | Unknown |
| Feb 2022 | ENGINE | Vehicle has less than 10,000 miles. Started making a loud noise and shuddering in the engine while at speed on the highway. Made it to dealer but was concerned we were going to break down before making it safely there. Service manager strongly suspects engine lifters (he drove it briefly with me and says this is a known issue with this truck & they currently have 3 other trucks in the shop with this same problem. He said parts are a 3-4 month wait and vehicle is not driveable, will break down, but couldn’t say when - could be 10 minutes, an hour, or a day. This happened to me on 2/1/22, while out of town on vacation. An hour on the phone with GM and was passed around to 3 different individuals. GM would not provide a loaner vehicle - leaving me stranded out of state. I had to get a rental vehicle on my own, GM claims they will reimburse me for a portion of this after 6-8 weeks. GM will not tow the vehicle home to Virginia (vehicle is in NC). I had to turn in rental car once I returned home because I can’t afford to keep paying for this on my own and it’s not a truck, which I depend on. Dealer is unable to fully diagnosis and document until end of week 2/7 or early week 2/14 as they are very busy. Unacceptable on ALL levels. | Crash: No Fire: No | Unknown |
| Jan 2022 | POWER TRAIN,ENGINE | 8 lifters in my vehicle needed to be replaced. While driving my vehicle (12/4/21), after the auto stop feature was activated my truck experienced a lack of power and hesitation. I then turned the truck off and upon starting it was making a knocking noise. I immediately checked the oil as I wanted to make sure there was oil in the engine. I had warning lights on the dashboard and drove it about 3 miles to the dealer to be repaired. While driving it to the dealer, it did not sound right and shook. I also experienced a lack of power and was concerned for the vehicle to stall out while in traffic. The dealership informed me this is an issue with the 2021 GMC Sierra with a 5.3L V8 engine. I had seen online that GMC issued a service bulletin to have the lifters replaced in the 2021 GMC Sierra that were on the lot before they were sold (early December 2021). If this is a known issue why weren't the lifters replaced in vehicles on the road before the ones sitting on the lot. 8 lifters were replaced by the dealership but there was a shortage of parts due to the nationwide problem. There were no warning lamps, messages prior to the failure. The only symptoms I had was shaking and lack of power as indicated above after the autostop feature was activated. I then drove about 2 miles and went into a store before coming out and having the loud knocking on startup followed by warning lights and messages. | Crash: No Fire: No | Unknown |
| Jan 2022 | UNKNOWN OR OTHER | The only way to get the heater to work on your feet is to turn off defrost, turn on only feet, turn on AC and sync both sides. I live in North Idaho and when you do this your windshield fogs up and freezes. I have taken this to the dealership and was state "Works as designed by GMC". To me this is unacceptable. I drive 90 miles each way to the airport and have to decide what condition i can live with. Completely frozen feet and a clear window or the reverse. | Crash: No Fire: No | Unknown |
| Jan 2022 | POWER TRAIN | When shifting into drive after reversing, truck will occasionally do a small thud and hesitate to move forward. This is from a stopped position after reversing, then braking, putting the truck into drive, then it happens when starting to move forward at very low speeds (I would say about 1-2mph). Vehicles recovers quickly, however it seems like a transmission mount or something may have issues. If another car were coming up quickly, or started going expecting you to start moving, the delay the thud and hesitation causes may be enough to cause a minor incident (assuming no high speed traffic coming up behind someone as they reversed out). This issue does NOT occur every time. I have owned the truck for 4 months, and it has happened only about 4-5 times in total. | Crash: No Fire: No | Unknown |
| Jan 2022 | POWER TRAIN,ELECTRICAL SYSTEM,ENGINE | Can turn vehicle off while in gear (drive specifically). When you let off the brake, the truck acts as if it is in neutral. Discovered in my driveway when accidentally forgot to shift into park when I pulled in and pushed the stop button. Truck turned off, which would only expect if in park (or neutral), let off brake, and it began quickly rolling backwards as if it was in neutral. Fortunately the brakes were working, but had any children been riding a bike on the sidewalk or walking by, my truck may have hit them. Had I been more distracted and not noticed initially, it could have rolled into the road and hit my neighbors truck. This behavior can be reproduced every single time, and I can easily supply video. | Crash: No Fire: No | Unknown |