Complaint volume
520 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
520 consumer-submitted complaints on record for the 2021 GMC Sierra, grouped by component category.
520 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 109 complaints, with an average reported failure mileage of 51,910 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 169
POWER TRAIN 64
ENGINE AND ENGINE COOLING 41
POWER TRAIN,ENGINE 29
ELECTRICAL SYSTEM 26
UNKNOWN OR OTHER 16
STEERING 13
UNKNOWN OR OTHER,ENGINE 12
ELECTRICAL SYSTEM,ENGINE 10
SERVICE BRAKES 9
520 total complaints on record
Latest complaints
| Date | Component | Summary | Severity | Mileage |
|---|---|---|---|---|
| Jan 2023 | ELECTRICAL SYSTEM | My truck’s battery is dead after sitting for a few days. There is a manufacturing deficit causing parasitic draw. This is a safety issue because it leaves us stranded after parking the vehicle for a few days. The General Motors dealership refuses to do it anything about it. They claim it’s normal. | Crash: No Fire: No | Unknown |
| Jan 2023 | EXTERIOR LIGHTING | During winter/snow driving snow accumulates on the headlights and causes a partial to total loss of visibility. This has happened multiple times during winter months. Cleaning the headlights requires exiting the vehicle in a potentially dangerous situation. This may occur after every few miles or less depending on the conditions. | Crash: No Fire: No | Unknown |
| Dec 2022 | ENGINE,FUEL/PROPULSION SYSTEM | 15000 MILES LIFTER FAILURE IN TRAFFIC HIGHWAY AT SPEED 70 MPH LOST POWER ENGINE FAILED MULTILANE HIGHWAY RUSH HOUR TRAFFIC NO WARNING FAILURE | Crash: No Fire: No | Unknown |
| Dec 2022 | UNKNOWN OR OTHER | I have a 2021 GC Sierra 1500, The guidance lines in the display when in reverse go from non-existent to barely visible and are not usable especially in sunlight. The service man at Miller Chevrolet in Marianna Fla says GMC is aware of the problem, that it was caused by the last update download and will be fixed by another download to correct the problem. He also says the same issue is nationwide and all trucks have the issue which I find hard to believe. 1.If that were true it would be a simple matter of a few lines of code to correct the problem. 2. I have been chasing this problem since October and have now made four trips to the dealership. 3. I cannot believe all trucks have this issue and also I suspect the same backup system is in all GMC vehicles regardless of type. 4. I cannot believe GMC would allow such a problem to exist since the last update download which was months ago. 5. I contacted GMC Customer Care in October after the dealership told me they had no idea what was causing the issue. I have had a case number [XXX] since that time. I was told on the first call that if necessary a Tech would be sent to fix the problem. Today I called asking for a tech to be sent only to be told I had to take it to another dealership and try them before a Tech could be sent! I have two questions, can you help with this and does this qualify as a "lemon law" case? Any assistance would be greatly appreciated. INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6). | Crash: No Fire: No | Unknown |
| Dec 2022 | SERVICE BRAKES | All 4 brake rotors are warped according to my local GMC dealership. They also told me all of the inside brake pads are worn twice as much as the outer pads, which in my opinion indicates a manufacturing and/or computer controller issue. Safety is an issue when the inside brake pad wears down to metal while the outers are still over 75% of new thickness. GMC dealer told me they're seeing this on countless Sierra trucks made in the past few years but there is no recall and GMC will not cover it under warranty. First symptom was slight pulsing while braking downhill. 2-3 weeks later my brake pad wear indicator read 82% front, 88% rear. The following day it gave me an error message saying "service brake monitor" so I took it to my GMC dealer which is when they told me my brake pads and rotors all need to be replaced but the truck only had 22800 miles on it at that time. They said it could still be driven and pass inspection. Since then I have contacted GMC about them covering it and I have not made any progress. GMC has had numerous brake issues resulting in recalls in the past 3-6 years but unfortunately this particular issue has not yet reached recall status. I hope this gets resolved before I am forced to pay for brake replacements out of pocket, which nobody should have to do on a vehicle with so little miles on it. The work order invoice I uploaded indicates ""pads at wear limit, both front and rear" but it does not specify what the technician and service advisor told me regarding only the inside pads are worn. However I do have a recording of the service advisor telling me that if needed. You'll also notice that I uploaded a copy of the state inspection done by them that same day which indicates my brake system passed the requirements. Please help. | Crash: No Fire: No | Unknown |
| Nov 2022 | FUEL/PROPULSION SYSTEM,FUEL SYSTEM, DIESEL | Within 100 miles after purchasing this truck from GMC (used with 74K miles)I got messages both on my phone and later through inspection at GMC service center that the DEF system had a problem. The check engine light came on then off as well.I was getting messages saying I only had so many miles before the DEF system needed more fluid even though the tank was full or near full. The dealer here in Tucson indicated there was a bulletin on this problem and ordered parts for the repair. I was informed it was not a recall and I would have to pay over $800.00 for this repair. To date the dealer has had my truck for 2 weeks. Additionally, another message said insufficient coolant flow so they are installing a new coolant pump to be paid for by an after market warranty which I purchased at the time I bought the truck. This repair is over $1000.00 | Crash: No Fire: No | Unknown |
| Nov 2022 | SERVICE BRAKES | The contact owns a 2021 GMC Sierra 1500. The contact stated that the grandson was driving in stop-and-go traffic, the braking system suddenly malfunctioned causing the vehicle to crash into the rear of a second vehicle. The grandson was driving approximately 10 MPH when suddenly while pressing the brake pedal to stop the message "brake failure" displayed before the vehicle crashed into the rear of the second vehicle. During the crash, no injuries were reported and a police report was taken at the scene. The vehicle was taken to the local dealer who replaced the master cylinder and brake booster and the failure was remedied. The failure mileage was 21,539 | Crash: Yes Fire: No | 21,539 |
| Oct 2022 | ELECTRICAL SYSTEM,ENGINE | The contact owns a 2021 GMC Sierra 1500. The contact stated that while operating the vehicle, the dashboard gauges, instrument cluster, and infotainment center malfunctioned and became inoperable. Additionally, while starting the vehicle, there was a loud cranking sound coming from the engine compartment and the vehicle would not immediately start. The vehicle was taken to the local dealer, but the cause of the failure was not yet determined. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 100. | Crash: No Fire: No | 100 |
| 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 |