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 |
|---|---|---|---|---|
| Jan 2022 | ELECTRICAL SYSTEM,ENGINE,FUEL/PROPULSION SYSTEM | Less than 300 miles on the vehicle and it has thrown an error code P2B60. Relating to the engine coolant flow control valve position sensor. I have taken it to my local GM service center and they cannot see me for weeks. As of this morning the check engine light has disappeared but my fuel economy has severely decreased. It seems suspicious and possibly dangerous that it showed a check engine light with a warning of reduction in engine power the night before and disappeared in the AM | Crash: No Fire: No | Unknown |
| Jan 2022 | STEERING,ELECTRICAL SYSTEM | Started vehicle up in public parking lot and it had service power steering and ESC messages. Vehicle could not turn and had to be towed to dealership. The problem has been confirmed by the dealer but they have had the vehicle for 2 days and cannot fix the problem. Dealer states code keeps coming up in BCM but they are not sure why or how to confidently fix it. There were not warnings or any symptoms of this problem as it drove to work fine that same morning. | Crash: No Fire: No | Unknown |
| Dec 2021 | ENGINE | Famous lifter issue in the l84 engine. Hundreds of documented complaints and current class action lawsuit. I had to stop on a busy highway and it caused unsafe passing and irritated humans. | Crash: No Fire: No | Unknown |
| Dec 2021 | ENGINE AND ENGINE COOLING | The contact owns a 2021 GMC Sierra 1500. The contact stated while driving 15 MPH and making a turn, the vehicle lost power steering assist functionality. Additionally, the brake pedal was depressed several times but failed to respond. The parking brake, traction control, brake, engine, and headlights warning lights were illuminated. The contact also stated that the warning message "Limited Power" was displayed. The contact stated that he depressed the brake pedal with his two feet from a standing position and the vehicle decelerated and he pulled into a driveway. The contact was able to continue to drive the vehicle. The vehicle was taken to the dealer who diagnosed that the vehicle software needed to be updated. The contact stated that the vehicle was repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 10,000. | Crash: No Fire: No | 10,000 |
| Dec 2021 | ENGINE | On 11/19/2021. While on the express way our truck started sounding really bad. We drove it slower to a gm dealer in Highland MI. They said we had a misfire. And there was nothing they could do at this time. We drove a little further and it got worse. We had to stop at a rest area. After dark and in the freezing weather. We had it towed to a dealer in Frankenmuth MI. Our truck has 11,800 miles . It has a diagnostics report of Valve lifter defects left bank. Starter had to be replaced. And now gm wants to only fix to affected bank . But on the unsold trucks they will repair both banks as stated in service bulletin N212353840 . If we have one bad lifter they should all be replaced as for this not to happen again. As of 12/08 2021 it is still in the shop [XXX] Thank you INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6). | Crash: No Fire: No | Unknown |
| Dec 2021 | ENGINE | 2021 GMC Sierra 1500 AT4 6.2L engine, Little over 15000 miles, Purchesed May 2021. Drivining down the interstate with out warning, engine starting making back fire sounding noise, with a noticeable loss of power, I requested On Star to do a vehicle diagnostics, no faults was reported, No check engine light, temp was normal, oil pressure normal. The noise was off and on at first and then remained constant. Fortunataly I was able to make it safely back to my residents. I parked the vehicle and did a scan code and it did not have any codes, I did a pending code scan and it had a P0300 code. I started the engine and the noise was louder at first and then got quiter after about 15 seconds of running the check enging light came on I shut the engine down and did another scan it gave me a P0302 code. I feel that the vehicle is unsafe to drive and could cause a accident if it locks up on the highway. I contacted GM and reported the issue, they said take it to a near by GM dealer, I told them that I felt the vehicle was unsafe to drive and they tried to contact me with road side assistance but I was unable to get anyone on the phone. I feel that GM is ingnoring a known issue and that this will result in accidents and possible loss of life. | Crash: No Fire: No | Unknown |
| Dec 2021 | POWER TRAIN,ELECTRICAL SYSTEM,ENGINE | Prior to this incident I had lifter failure on my 2021GMC SierraAt 8464 miles, I was on my way to work and I heard a loud bang and I had to pullover off the highway, my dad had to come all the way out To get the vehicle because it had major engine damage and it was on a holiday so no one would come help me.The vehicle was in the shop for over a week getting these repairs done, upon receiving vehicle it had been a week and I received service four-wheel-drive messages on the dash.Trying to use four-wheel-drive after this was a no-go every time I push the button nothing would happen it would stay in two wheel drive.After this I made an appointment with the dealership for this issue to be fixed, as I was going to get readyTo leave again with the truck having no issues other than what I’ve stated when I went to go start the truck nothing happened at all every light lit up on the dash and part of me thinks it’s an electrical issue but the Other part of me thinks the motor is locked up. Also the lights would not shut off when I turn the vehicle off so I’ll have a dead battery in the morning. | Crash: No Fire: No | Unknown |
| Nov 2021 | ENGINE | Valve lifter defects. June, 2021: 7,619 miles: left side valve lifter defect necessitating need for valve, push rod replacement on left bank of engine November, 2021: 13,171 miles: right side valve lifter defecting necessitating need for valve and push rod replacement on right side of engine | Crash: No Fire: No | Unknown |
| Oct 2021 | STEERING | POWER STEERING STOP WORKING | Crash: No Fire: No | Unknown |
| Oct 2021 | STEERING,ELECTRICAL SYSTEM,SERVICE BRAKES | I started my truck this morning, drove it 3 miles, and all of a sudden got an ESC warning, Parking break warning, and a degraded power steering warning all at one time. My steering wheel started vibrating vigorously, a clanking sound started under the hood somewhere, and none of my safety features worked after.. Cruise Control, Vehicle Collision Control, Vehicle Gap sensors, etc.. The vehicle is currently at the dealer being looked at. | Crash: No Fire: No | Unknown |
| Oct 2021 | TIRES | I noticed a sway in the vehicle while driving down the highway, bad enough to pull over and check the tires and suspension. Took truck to dealer where upon inspection I was told that the cause was the tires' sidewalls are not stiff enough and the tires try to follow the grooves in the road. The dealer recommended changing the tires but had to defer to General Motors who denied the tire change under warranty. GM informed me that this is a normal condition of the tires on roads that have grooves cut in and would not be covered under warranty. I explained that I do not feel safe towing a trailer behind this truck and was told that they could not replace the tires but offered me multiple options for my trouble including: Onstar, service voucher which cannot be used on tires, accessory voucher which cannot be used on tires, and a wheel and tire protection plan which would not cover the issue at hand. I declined all of the offers as my only concern is having a truck that is safe to tow a trailer behind and new tires are required in order for me to have that. The truck is designed to be able to tow a trailer and I am too concerned to tow behind my brand new truck because the truck would induce a sway into the trailer posing a significant safety risk to myself and other motorists on the road. If this is a known issue, which it seems to be, then General Motors should not include these tires on trucks sold in markets with grooved pavement to reduce the risk of accidents resulting in injury or even death. I shouldn't have to spend an additional $1200+ on new tires for a vehicle that was less than a month old when I took it into the dealership. | Crash: No Fire: No | Unknown |
| Oct 2021 | AIR BAGS | Vehicle purchased new in 2021; has less than 5,600 miles on it. Service Restraint System indicator light began coming on in September. At first intermittently, then every few seconds. Sent vehicle to dealer for repair on 9/27/21. Dealer states not safe to drive because airbag may not deploy in case of accident. | Crash: No Fire: No | Unknown |
| Sep 2021 | ENGINE | a lifter went out. While driving on a turnpike going 80 mph the engine starting knocking. The truck had to be towed to a GMC dealership where they confirmed a lifter went bad. the truck is a v8 with 8,000 miles on. the dealership advised what the problem was and replaced 4 of the 8 lifters. No warning was given, as soon as the lifter went out there were all sorts of errors that started showing up including emissions issues. | Crash: No Fire: No | Unknown |
| Sep 2021 | ENGINE | While driving on the highway my truck started to buck and had a loud engine knocking noise. Speed was greatly reduced so much so that I was going under 45 mph in a posted 65. The check engine light did not come on. While sitting on the side of the highway there was a severe engine knock only when the revs on the engine were increased. Oil pressure and cooling temps were as they should be. The next day on the way to the dealership the engine started knocking. This time the check engine light came on, speed was greatly reduced at this time. After about five miles the knocking stopped and the check engine light went out. The Dealership checked it out and stated the lifters were bad. It seems that this is a known issue with GM. I was told by the Dealership that there were two other trucks ahead of me with the same issue. Also, because this is such a prevalent issue with GM, they cannot keep up with the demand for parts. My Dealership is waiting for a head gasket. GM has known about the faulty parts for approximately two years, and they are only replacing some of the faulty, poorly made parts, hoping the other side of the engine will not develop issues and fail. I feel this is placing the driver and occupants at risk while driving down the highway and not being able to maintain posted speed limits, or just locking up and engine, and coming to an abrupt stop. | Crash: No Fire: No | Unknown |
| Sep 2021 | FUEL/PROPULSION SYSTEM | I have had my gmc sierra 1500 for 2 weeks and it has less then 200 miles on it the first week I lost power the check engine light, air bag and traction control light started flashing and since then my engine light has be solid with code P0300 and it will intermittently loss power and start flashing. The dealer has it now but cannot figure out the issue. Total unacceptable for a brand new vehicle. | Crash: No Fire: No | Unknown |
| Sep 2021 | ENGINE,FUEL/PROPULSION SYSTEM | The truck has 7500 miles on it and the check engine light keeps coming on then goes back off. It is impossible to schedule service as the light goes off before it gets to dealer. The when driving the truck many times the check engine light will flash for a minute or so and then remain on steady. This is very frustrating and the dealer has found nothing. It has happened probably 10 times since the truck was new and continues now. The truck was just serviced and the dealer found nothing causing this. | Crash: No Fire: No | Unknown |
| Aug 2021 | STEERING,SERVICE BRAKES,ENGINE | Driving the car it started backfiring and then the ESC light came on and the car engine seemed to become erratic as well as steering and braking error messages and the check engine started blinking. Very scary before I got it pulled over and very thankful I wasn’t on the highway etc. I’m seeing all the issues online sounds like the supposed fixes for the 2019 models having issues aren’t solving the problem. I bought mine in April and 4 months later it’s become unreliable. | Crash: No Fire: No | Unknown |
| Aug 2021 | SUSPENSION | On 22 December 2020, I received a 2021 GMC Sierra 1500 SLT X31 Truck. The day that I drove it I notice that the Truck was riding as though it had a low Tire issue. It was riding bouncy. I had no low tire light. I checked the Tire Pressure and they all was over inflated. I brought the pressure back to range, but the Truck was riding the same over rough and bumpy roads that the rear end of the Vehicle was shifting from side too side when you hit a bumpy or on rough roads. it felt like the rear end was coming off the ground very frighten. I called GM they assigned a case number and I took the Truck to Three dealership with the same answer that all bolts were tighten to Spec. Ok I get that, but did not address the problem that the truck is doing. I am not comfortable driving this truck especially when you have no I deal when your terrain will change and the back end of y0our Vehicle moves from side to sider on you. | Crash: No Fire: No | Unknown |
| Aug 2021 | ENGINE | Bought GMC Sierra 1500 brand new. At approximately 2300 miles the engine light started blinking. I took it in and they said they couldn't find anything wrong with it. At 3700 miles it started again and I took it in. It has a bent push rod causing engine failure. | Crash: No Fire: No | Unknown |
| Jul 2021 | ENGINE | GM has a lifter problem that causes complete engine failure. When this happens the engine completely locks up rendering the vehicle completely shutdown. This is happening over and over in early stages of 2021 Chevrolet and GMC Vortec V-8s. Mine happened at 13000 miles on a 2021 6.2L GMC Denali, and GM is only fixing the problem partially and as I understand with the same defective product that just failed. Also it is known this failure likely will happen again as it is a design flaw. If this happens in the wrong traffic situation it will be very dangerous. I am very concerned. When my vehicle was towed to dealer they had 7 other 2021 complete engine failures just like mine waiting for repair. | Crash: No Fire: No | Unknown |
| Jul 2021 | ENGINE | The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving in inclement weather, the vehicle stalled without warning. The contact looked under the vehicle and saw that engine oil was leaking from a puncture in the oil pan. The vehicle was towed to the local dealer however, the cause of the failure was not yet determined. The manufacturer was notified of the failure. The failure mileage was 5,800. | Crash: No Fire: No Towed | 5,800 |
| Jul 2021 | STRUCTURE | The contact owns a 2021 GMC Sierra 1500. The contact stated while driving 20-30 mph, she heard abnormal noises coming from the trunk of the vehicle, with no warning lights illuminated. The vehicle was taken to the dealer, where it was diagnosed that the dash line had detached from its holder and was rubbing against the frame of the vehicle. The vehicle was repaired, however, the failure persisted. The vehicle was taken back to the dealer who diagnosed that the drive axle, band, and rear pinion needed to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The approximate failure mileage was 420. | Crash: No Fire: No | 420 |
| Jun 2021 | AIR BAGS,SEAT BELTS | Airbag light and "Service Safety Restraint System" keep flashing on and off intermittently. Sometimes every 5 seconds. Sometimes once or twice a day. This is a known issue with 2021 GM trucks and SUVs. Trying to get vehicle in for service but dealer said they are booked 2 weeks out and won't given loaner vehicles at all anymore. The vehicle has less than 2000 miles on it. | Crash: No Fire: No | Unknown |
| Jun 2021 | LANE DEPARTURE | The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at undisclosed speeds, the Lane Departure Assist warning failed to activate when the vehicle drifted out of the driving lane. The failure was intermittent. The cause of the failure was not yet determined. The vehicle was taken to the local dealer who was unable to identify the cause of the failure. The contact was informed that the vehicle operated as intended. The manufacturer was notified of the failure. The failure mileage was 100. | Crash: No Fire: No | 100 |
| May 2021 | ELECTRICAL SYSTEM,ENGINE | This is the second time I stop at the grocery store for about 15 or 20 min, get back in the car push the start, then the truck keep cranking with no start for about 20 seconds. Then I try second time and it fires up. | Crash: No Fire: No | Unknown |