10.0

really awful
Crashes / Fires:
0 / 5
Injuries / Deaths:
0 / 0
Average Mileage:
7,994 miles

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« Read the previous 20 complaints

problem #97

Mar 302025

Sierra 1500

  • miles
July of 2023, lifters failed on left side of engine. Lifters replaced and cam shaft replaced. January 2025, lifters failed on right side of engine. Replaced. March 2025. Engine seized on interstate. Truck lost all power while driving, no warning signs prior. Dealership has no rental vehicles and we are not old enough to rent from a third party company so family had to drive 9 hours to our location so we wouldn-??t be stranded. Three times this truck has failed us. GM is putting in a new motor as it-??s still under warranty, but the new motor has no additional warranty. So basically this new motor will be warrantied for less than 7k miles. They cannot say if the new motor has the remanufactured lifters or not. So we could be facing the same exact issues. Can-??t ever get ahold of anyone directly though GM.

- Colorado Springs, CO, USA

problem #96

Dec 122024

Sierra 1500

  • miles
Transmission recall was performed at a gmc dealership. Vehicle has been the the shop repeatedly since. Coolant control valve crank case position sensor new catalytic converter and dpf system. New low temp coolant loop pump. In the shop now for another low temp coolant pump that-??s been shorted out. Seems to have on going electrical issues since recall was performed

- Oneida , NY, USA

problem #95

Mar 152025

Sierra 1500

  • 80,000 miles
The contact owns a 2021 GMC Sierra 1500. The contact stated while driving 70 MPH, several unknown warning lights illuminated, with the message to shift to neutral displayed. The contact pulled over to the right side of the road and attempted to restart the vehicle; however, the vehicle failed to respond as needed. An unknown dealer was contacted. The contact stated that the failure had occurred on several occasions. The vehicle was towed to the dealer, where it was diagnosed that the engine was damaged and needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and offered a monetary payment. The approximate failure mileage was 80,000.

- Noblesville, IN, USA

problem #94

Apr 142025

Sierra 1500

  • 27,000 miles
The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, there was an abnormal sound coming from the engine compartment. The contact pulled over to the side of the road and discovered that the engine oil level was low. The check engine warning light was illuminated. The failure occurred on several different occasions. The vehicle was taken to a dealer, where it was diagnosed that the lifters needed to be replaced. The vehicle was repaired; however, the failure persisted. The vehicle was taken to a different dealer (Legacy Westbank Buick GMC; 3611 Lapalco Blvd, Harvey, LA 70058) to be diagnosed. The vehicle was not diagnosed or repaired. The contact was taken to a different dealer (Mossy of Picayune; 241 Frontage Rd, Picayune, MS 39466) where it was diagnosed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 27,000.

- Chalmette, LA, USA

problem #93

Apr 072025

Sierra 1500

  • miles
Driving 75mph towing a 24' trailer and the motor just shut down and almost caused a massive pile up on [XXX]. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Lebanon , IN, USA

problem #92

Apr 062025

Sierra 1500

  • miles
at 16,000 miles Bank 1 lifters fail and replaced under warranty. now at 90190 miles Bank 1 lifters have failed again this time damaging the camshaft. I have all the service records for this engine and I was verbally assured by GM in 2021 that they would cover this repair until 100,000 miles. I know from looking on Google and talking with service advisors at GM that the 6.2L ecoTec3 V8 engines are having multiple problems related to my issue. GM should be able to warranty this engine to 100,000 miles and from past experience this engine should last 200,000 with good service.

- Georgetown, TX, USA

problem #91

Mar 272025

Sierra 1500

  • miles
Engine failure. Engine Locked up and truck shut down in the middle of the Freeway. Barely made it to the side of the road.

- Navarre, FL, USA

problem #90

Mar 262025

Sierra 1500

  • miles
Driving on highway at approximately 70 mph and the engine completely cut off without warning. Error message on dash said put car in neutral and press the start button. After safely pulling over, the vehicle was never able to start or even crank. Towed back to the dealership. Catastrophic engine failure according to the dealership. Vehicle has the 6.2 V8 engine with known issues by GMC apparently. Only 32k miles and under warranty but dealership reports that replacement engines are on back order and they have not been able to source one.

- Haverhill, MA, USA

problem #89

Mar 282025

Sierra 1500

  • miles
Lifter failure resulting in damage cam shafts

- Weirton , WV, USA

problem #88

Sep 012024

Sierra 1500

  • miles
At cold start-up, engine (6.2) makes a metal-to-metal grinding sound for 60-90 seconds. After warm-up, a steady tick on the right side of the engine while running. I contacted GM and they said, " this was normal at start up". however, with me being a mechanical engineer, all of my school and working experience tells me anything grinding metal to metal is not good.

- Fort Worth, TX, USA

problem #87

Mar 302025

Sierra 1500

  • miles
Engine seized and now we need a new motor

- Radcliff, KY, USA

problem #86

Dec 182023

Sierra 1500

  • 20,000 miles
The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 30 MPH, there was an abnormal knocking sound coming from the engine compartment, after which the vehicle lost motive power. The contact was able to pull over to the side of the road. No warning lights were illuminated. The vehicle was taken to a dealer, who determined that the engine needed to be replaced. The vehicle was repaired. The contact stated that prior to the engine failure, the transmission was replaced. The manufacturer was not notified of the failure. The failure mileage was approximately 20,000.

- Beverly Hills, MI, USA

problem #85

Aug 022021

Sierra 1500

  • miles
My truck was part of a GM buyback program where GM Corporation bought the truck back to fix it around Aug 7th 2023 for engine problems. I am reporting this because I do not believe that GM ever reported this to NTSHA. There are also other issues happening at the same time period that should be looked into that may or may not be coincidences. At or before 10,126 miles the truck started having engine lifter and other engine issues. General Motors will not tell me exactly what was done other than lifters according to paperwork supplied. It may have had other issues like a spun bearing but it was never disclosed. Can NTSHA please look into this and information is found, could I please get the records. I asked for the paperwork of what was done while GM owned and troubleshot all the problems. I was told that information is only available to the original owner and I could not have it. It is very frustrating when General Motors Corporate use owner-??s personal data as a way to hide what was done and not have to disclose required information. I am asking for service records while General Motors owned it and the service records they did to fix it. I know that there are many more engine problems that are not documented on the vehicle summary. GM will not buy back the truck over a few lifter issues. The truck was later fixed and Art Gamblin Motorsv in Enumclaw Wa, purchased it. I am told it is fixed but have no real paperwork proving this, I was able to purchase an extended warranty just in case. There is also quite a few of battery and electronic issues that do not seem normal with the car as well. The battery was replaced at 10,126 miles at the same time as the engine issues and the battery module was replaced at 29,536 miles. At 29,875 miles and 29,965 some type of communications module and On Star module was replaced. This is the around the same time as the truck was having engine issues and was eventually bought back for what is called -??engine noise-??.

- Port Orchard, WA, USA

problem #84

Mar 152025

Sierra 1500

  • 63,000 miles
The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 60 MPH, there was an abnormal knocking sound coming from the engine compartment, after which the vehicle lost motive power. The contact was able to pull over to the shoulder of the roadway, where the vehicle failed to restart. The check engine warning light was illuminated. The vehicle was taken to an independent mechanic, who determined that the engine had seized. The contact was also informed that the fuse box needed to be replaced. The vehicle was repaired, but the failure reoccurred. After investigating the failure, the contact related the failure to NHTSA Action Number: PE25001 (Engine, Engine and Engine Cooling). The manufacturer was not notified of the failure. The failure mileage was 63,000.

- Santa Ana, CA, USA

problem #83

Dec 142024

Sierra 1500

  • miles
After 2 years of owning the vehicle, after every oil change, it would indicate low oil just before an oil change causing for us to add an additional a quart of oil to keep it running smoothly. We informed the service technician of the situation on multiple occasions and no further inspection was completed, and just an oil change was serviced. After a few months we noticed the engine was running rough and a white smoke coming out of the exhaust on acceleration then the check engine light came on. We brought the car to get tires replaced and to service the check engine light, the technician stated that the check engine light a failure in the catalytic converter. We brought the vehicle to the local GMC service center, where they indicated that the we required a replacement engine because of catastrophic engine failure. We reported that the check engine light was due to catalytic converter failure. The service technician ensured that the priority was the replacement of the full engine not indicating what was the main cause of engine failure stating that the catalytic converter could have led to the failure of the engine as well. We replaced the engine, and after 3 months of vehicle being in the shop the engine was replaced. Three days after receiving the vehicle, a check engine light came on. We did not drive the vehicle until we had to return it back to the service center. The service technician stated that it is due to a lack of communication from the engine to the ECU. The technician called the following Monday stating that the check engine light was due the catalytic converter. We told the technician that was the primary reason that the customer the vehicle in the first place. We asked if there was an alternative to replacing the catalytic converter since we already paid 12k for the engine replacement. We asked if they had taken apart the catalytic converter to confirm its not a sensor issue. They replied that the codes indicates its the whole converter.

- Parrish, FL, USA

problem #82

Mar 062025

Sierra 1500

  • miles
[xxx], I purchased a 2021 GMC Sierra 1500 from faulkner Chevrolet in bethlehem, pa. I test drove the vehicle before purchase and it showed no indication of any mechanical issues that I was able to detect. I was shown by the dealership the carfax and was informed that there are currently no recalls for the vehicle. I was led to believe that the vehicle was in good condition and safe to drive and, therefore, agreed to purchase the vehicle for the aforementioned price (including tax and title fees). I purchased the vehicle with 60,077 miles on it, and after driving it normally for only 5 days (on [xxx]) it broke down and I was stranded on the highway 16 hours from home. I was able to get the vehicle towed and paid $1,200 for the starter to be replaced, which is what the mechanic suggested but this ended up being entirely unnecessary as the real issue was due to a catastrophic defect in the engine. After the starter was replaced, I was driving the vehicle only a few days later (on [xxx]) and it suffered a catastrophic engine failure while driving 70mph on the highway. I lost control of the vehicle and nearly got in a collision with another vehicle. I was able to get the vehicle to the nearest auto shop and after inspecting the vehicle they informed me that there is a serious engine issue relating to a seized bearing and the engine will need to be rebuilt entirely. At this point it had been only 12 days since the purchase and the odemeter read 61,662 (1,585 miles driven since purchase). Due to the faulty vehicle, I was forced to pay to have the vehicle shipped from the location where it broke down to the dealership where I originally bought it (around $1,200). Faulkner Chevrolet knowingly sold me an unsafe vehicle that they were well aware had a defective 6.2L V8 engine. This defect is currently under investigation by the NHTSA and faulkner Chevrolet purposefully ommitted this crucial information until after the vehicle was sold. Clearly, this is an unethical bus information redacted pursuant to the freedom of inform

- Schuylkill Haven, PA, USA

problem #81

Feb 182025

Sierra 1500

  • miles
I was driving 50mph when my check engine light started flashing. The engine had very little power and there was a new consistent engine knock. I took to GMC dealership and they informed me that half of the engine lifters failed and a pushrod was bent. There was no warning prior to the incident. I have had the vehicle serviced only at the dealership and have only used premium fuel. The truck has 88,000 miles.

- Chesterfield, MI, USA

problem #80

Jan 022025

Sierra 1500

  • miles
I've now had 2 engines fail catastrophically, One at 19,191 miles and the second failure at 80,661. Both are the 6.2L engine. The first had crank bearings that were black. The second I was not informed of the cause but that it was seized leaving me stranded on the roadside.

- Holly, MI, USA

problem #79

Nov 062024

Sierra 1500

  • miles
Engine failed and had to be replaced. GMC was absolutely no help had to bring to local gas station where i had to pay almost $12,000 to get it fixed. The truck has been in shop frequently for oil issues with this motor but GMC just jerks you around. I am in sales and need my vehicle to support my family

- West Islip, NY, USA

problem #78

Feb 162025

Sierra 1500

  • miles
While driving the vehicle shut off in the middle of the roadway. It sat in the road till it got towed. Brought it to the dealership where it was purchased and they said the engine was blown. Themis vehicle is equipped with the 6.2 motor. It happened February 16th. The dealership confirmed the engine failed. It is siting currently at the dealership and could be available for inspection.

- Thorndike, ME, USA

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