GMC Sierra Complaints (2021)
671 consumer complaints on file.
- #11664796June 4, 2025FUEL/PROPULSION SYSTEM
- #5 injector failure, no. - Once the injector failed, the vehicle would violently shake when trying to accelerate. - Yes, was not covered under factory warranty but replaced by third-party extended warranty. -Yes, replaced by the dealership. -No warnings prior, once the injector failed warning for brake system check and vehicle mileage limits set in warning.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11664514June 3, 2025POWER TRAIN
received my truck back after replacement of the front transmission pump and idle gear, the same day the transmission had horrible down shifts, sometimes it would just downshift into neutral and bounce off the rev limiter. the service advisor told me that my transmission had to "relearn" my driving habits when I called him and would take 200-400 miles.. i drove it one more day and drove it back to the dealer to have them drive it. the agreed that something was wrong, but didn't know what and had to contact gm engineers. 2 days later they told me that the valve body needs to be replaced. I dropped it off to find out that it had been ordered with zero ETA of when they will receive it.. so now im stuck with a loaner and no ETA on when parts will be available.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11664640June 3, 2025ENGINE AND ENGINE COOLING
The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was unavailable. The dealer was not contacted and confirmed that parts were not yet available. The manufacturer was not made aware of the failure. The contact had not experienced a failure. VIN tool confirms parts not available.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11664456June 2, 2025AIR BAGS, WHEELS
• The airbag system failed to deploy during a collision that resulted in the total loss of the vehicle. Additionally, the vehicle was operating with a 17” spare tire (undersized compared to the standard 20” wheels), which may have contributed to the accident. The vehicle has been totaled and is currently in the possession of the insurance company, but may be available for inspection upon request. • Despite the severity of the collision, none of the airbags deployed, which could have resulted in serious injury if the circumstances were different. The use of an undersized 17” spare tire may have affected the vehicle’s stability, braking, or performance, contributing to the crash. • No. The vehicle was declared a total loss and has not been evaluated for defect reproduction by a dealer or service center. However, I am aware of related recalls and lawsuits regarding both improper spare tire sizing and airbag non-deployment in 2020–2021 GMC Sierra models. • The vehicle has been inspected by the insurance company during the total loss evaluation. A police report was also completed at the scene of the accident. To my knowledge, the manufacturer (GM) has not inspected the vehicle at this time. • No. There were no warning lights, messages, or symptoms prior to the crash. The vehicle gave no indication of any issue with the airbags or tire compatibility leading up to the accident. I was involved in an accident in my 2021 GMC Sierra. At the time, the vehicle was operating with a 17” spare tire installed, which I later discovered may be significantly undersized compared to the standard 20” wheels. During the crash, the impact was severe enough to total the vehicle, but none of the airbags deployed. Fortunately, there were no injuries, but I believe the non-deployment of the airbags represents a critical product safety defect. I’ve since learned that GM has recalled similar vehicles for incorrect spare tires, and that lawsuits have been filed regarding calibration issues.
- Crash:
- Yes
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11664458June 2, 2025ENGINE
Engine seized while at idle speed and has to be replaced. It was a catastrophic event, but not covered under the current recall for 6.2L L87 engines.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11664208June 1, 2025VISIBILITY/WIPER
I don't believe this needs to have an investigation, but i would like it documented and brought to GM's attention for future body designs. I have never had as many rocks/debris hit my windshield as I have with this truck. I have had one chip in a windshield in 30+ years of driving, until this truck where I have had several that needed repairs, and this last one has created a Crack large enough where my windshield needs replaced. It may be bad luck, but I've talked to multiple other Sierra owners and most of them have had the same issue. A couple have had the windshield replaced almost yearly. Please at minimum inform GM engineers to possibly determine the cause (I assume aerodynamics) so they can incorporate the flaw (if there really is one) into future designs. The photo I included happened almost immediately after the impact. The crack has grown several inches since as expected.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11664233June 1, 2025ENGINE, SERVICE BRAKES, STEERING
While traveling on the interstate the vehicle lost all propulsion and started to rapidly decelerate. Shortly after propulsion was lost the engine turned off completely affecting the steering and braking of the vehicle. The vehicle was towed to the GMC dealership that we purchased it from. repairs have not begun so I assume it would be available for inspection. We were traveling on a three lane interstate up a grade at 80 MPH. Had I not been able to safely get the vehicle stopped and out of traffic or had we lost control going down a grade we would not have been able to stop the vehicle and there would've potentially been a catastrophic accident most likely resulting in injury or death. No the dealership has not diagnosed the failure physically. The service writer did suggest that it sounds like the failure reported from the recall not being addressed. I did contact the dealer about the recall on Saturday May6th. At which time I was informed there was not a solution for the vehicle for my vehicle at that time. There were no warning prior to the incident. After the engine stopped operating there was a warning produced on the instrument panel that read "Engine Oil Hot" and the instrument panel no longer registered any oil pressure.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11664081May 31, 2025POWER TRAIN
Reached the 100,000 mile mark and the truck started shuddering. Took it to the dealership and they tell me the torque converter is coming apart and I need a new transmission.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11663930May 30, 2025POWER TRAIN
front idler gear for the transmission pump failed at 39500 miles. was fixed under GMC warranty. but now after getting the truck back the transmission has extremely harsh down shifts. still waiting for GM to figure out what to do next..
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11664010May 30, 2025POWER TRAIN, ENGINE
My truck has a known recall from GMC which results in total loss of propulsion. It has not failed yet, but this is dangerous to me, my family/kids, and potentially others on the road. I have made multiple attempts to speak with GMC about the issue and also my local dealer. Neither group will provide concrete information as to when they can look at/service my truck even though there is a known remedy - [XXX] I brought my car into the dealer December of 2024 for brakes and also a rattling noise since it was uncharacteristic. Noises can be indicative of this larger problem (which I know now and didn't then) but they "didn't hear a rattle" and the "condition could not be duplicated" which is patently false since it still makes the noise/has gotten worse. Since then, I have taken the following actions: - I called and spoke with the local dealer service team on 5/5 - was told since it's showing incomplete, no remedy available there was nothing they could do - Spoke with GMC on 5/5 - they directed me to the local dealership - Made an appointment online on 5/10 to get my truck serviced and to check for this problem - They immediately called me first thing on Monday 5/12 to cancel my appointment and again tell me there is nothing they can do about this issue - I have continued to express my safety concerns to both parties - I spoke to GMC today, 5/30 and was told that there is no timeline for the issue (with my VIN) even though the remedy is known - An appointment is scheduled on 6/12 with my local dealership, but if I recall status hasn't changed, they will not check for this problem INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11663728May 29, 2025POWER TRAIN, ENGINE
The truck ever since of bought it has been nothing but issues. Starting with the fuel pump issues then electrical issues and most recently the coolant flow control valve. This is my work truck and now I’m out of a truck with no loaner and the dealership has no eta.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11663566May 28, 2025ENGINE
I’m filing a complaint regarding GM Recall N232404000/N232404002, which affects the L87 6.2L V8 engine in my 2021 GMC Sierra 1500 AT4. This recall is tied to a serious defect that can cause sudden loss of propulsion due to internal engine failure. My vehicle has shown symptoms since purchase — including engine ticking, unusual noises, and low oil levels — all documented by dealership service records. GM originally instructed dealers to replace engines based on build date, which made sense given the nature of the defect. But now they’ve changed the remedy midstream. Instead of replacing potentially defective engines, they perform a PicoScope test, and if it “passes,” the only action taken is replacing the oil with a different grade. This does nothing to resolve the underlying issue. How does a manufacturer go from replacing engines due to internal failure risks to simply changing the oil and calling the problem solved? This undermines the purpose of a safety recall and places future liability on the consumer. A known internal mechanical defect cannot be fixed with an oil change, yet GM is closing out cases this way. Now I’m stuck with a vehicle I can’t fully trust — one that may still fail unexpectedly — and possibly face diminished resale or trade-in value due to an engine that other buyers will view as unreliable or patched over. GM is leaving owners with the long-term risk while clearing their books of liability. I urge the NHTSA to investigate whether this revised approach truly meets federal recall standards.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11663217May 27, 2025ENGINE AND ENGINE COOLING
The contact owns a 2021 GMC Sierra 1500. The contact received notification of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was unavailable. The dealer was contacted; however, the contact was informed that parts were not yet available for the recall repair. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts not available.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11662754May 23, 2025ENGINE
Unknown There is a recall on the this model but with different motor but when I took mine in they said it was a.manufactured defect but I was out of warranty because I purchased it cash and didn't get extended warranty now im having to replace and pay for a head and new engine over 10,000 when vehicle doesn't even have 70,000 miles it started with a engine light going on amd off for 2 weeks then it just stopped working It's too coincidental that the sister truck make n model to this had a recall for exactly what is wrong with mine
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11662535May 22, 2025ENGINE
We have the 6.2 liter GM engine that has lost propultion. We are not covered in the recall and are 30,000 miles above the milage warranty, but still within the time portion of the warranty. GM payment assisitance has only offered us $1600 to help with replacing our engine. The dealership told me their warranty parts price was higher, so it really didn't offset any cost. This is our ONLY vehicle for our small appliance repair business. Our vehicle was manufactured at the plant in Canada where all the other faulty engines were manufactured. Please consider widening the recall to include our vehicle.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11662387May 21, 2025SERVICE BRAKES
Parking brake locking up. There is recall on the brake module for my year make and model but my vehicle isn't on the list and I feel it should be. I'm having the same issues as they are. I can't drive it until it is fixed. Very dangerous.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11662109May 20, 2025ENGINE
My GM 6.2L V8 engine has seized in less than 100K Miles. Thankfully not whilst driving and being potentially harmful to myself or others with the catastrophic failure. This problem is being widely report and continually occurring. GM is saying that I am not included in the massive recall for this, However NHTSA notes the vin range as NR and indicates incidents are still occurring. Seems to be a real lemon situation here and even bigger a letdown to uphold consumer safety.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11662126May 20, 2025ENGINE, POWER TRAIN
Engine has stopped a couple of times at low speeds, Was able to restart and continue. Engine will occasionally make a "straining / Dieseling sputtering sound" when execellerating from low speeds or Stop. Transmission will make strange and strained shifts from time to time. This is reaccruing problem that comes and goes over the last approximately 2 yrs since about 9000 miles to current approx 25000 miles.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11662133May 20, 2025ENGINE
The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the low oil warning light illuminated. The vehicle was taken to the dealer but was not diagnosed or repaired. The manufacturer was made aware of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 67,600.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11661854May 19, 2025ENGINE
code P1098. Engine light comes on, power is reduced, coolant fan runs on high. Temp gauge fluctuates. This last for 20 minutes or so. The engine then returns to normal. After a few days the engine trouble light goes off. This happens every several weeks. Parts are backlogged and I understand this is a common problem with this engine. I have 64000 on it.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0