10.0

really awful
Crashes / Fires:
1 / 1
Injuries / Deaths:
0 / 0
Average Mileage:
9,583 miles

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problem #174

Nov 042025

Sierra 1500

  • miles
At 96,000 miles (3,000 miles after the extended warranty expired), I noticed the "GM tick" more prominent and had more of a metallic sound than it ever did. Upon further investigation, it was found that a collapsed lifter may be the culprit. The truck was brought to the dealer and it was confirmed that the #1 hydraulic lifter had collapsed and needed replacement. This work was approved and tonight, I received a call from Rivard Buick GMC saying that the collapsed lifter also caused significant wear on the camshaft which also now requires replacement. Loss of power on the road poses a significant risk as I carry my children in the vehicle. No warning lamps, messages, or other indicators appeared before or when the issue occurred. The issue was reproduced by the manufacturer/dealer. The dealer Service Manager confirmed that this is extremely common with these trucks with the 6.2L engine and said it was a design flaw due to Dynamic Fuel Management, as well as the oil viscosity recommendation from GM being too low. The year group before and after the 2020 has been recalled along with TSB's issued, however, this group is not part of it. I contacted GM Customer Service (Case [XXX]) and was offered a 10% discount on the repair, being told that this is a "great deal considering the vehicle is out of warranty". GM Customer Service has now resorted to not answering any further questions after several attempts to reach someone. This is also after replacing the 10-speed transmission that was also not part of any recall but that was such an issue that the dealer was only able to source used transmissions rather than new parts. Clearly GM won't make the right decisions to back their products or customers, so NHTSA intervention is necessary. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Riverview, FL, USA

problem #173

May 012025

Sierra 1500

  • miles
The motor went to knocking and lost power. Cost us about 3500. To fix. Lifters went down cam went down which caused major motor knock and loss of payer

- Elkton, KY, USA

problem #172

Feb 252026

Sierra 1500

  • 37,061 miles
The contact owns a 2020 GMC Sierra 1500. The contact stated that while driving at various speeds, the steering wheel became stiff and difficult to steer to the left or the right. The power steering and check engine warning lights were illuminated. The vehicle was towed to a local dealer, where it was diagnosed with a corroded body ground strap. The error codes were cleared, and a test drive was performed. The vehicle was repaired out of pocket. Upon further investigation, the contact related the failure to the GMC Customer Satisfaction Program: N252515590; however, the VIN was not included. The manufacturer was not made aware of the failure. The failure mileage was approximately 37,061.

- Joliet, IL, USA

problem #171

Jul 102024

Sierra 1500

  • miles
Misfiring due to DFM which is a common issue. Running a scan confirmed. I have installed a AFM/DFM disabler which seems to fix the issue.

- Elizabeth City, NC, USA

problem #170

Jan 022026

Sierra 1500

  • miles
Have not had my truck in over a month while it-??s getting repaired had engine failure sure to faulty hydraulic lifters and camshaft failure due to the Dynamic fuel management system purchased warranty for my vehicle but this needs to be looked into it is unfair as a consumer that they are not doing anything about 2020 models and earlier they are just focusing on 2021 and up. They almost had me crash my truck due to power loss

- Connor Township , ME, USA

problem #169

Feb 202026

Sierra 1500

  • 44,000 miles
The contact owns a 2020 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, there was a loud rattling sound coming from the engine. There was no warning light illuminated. The vehicle was taken to the dealer, where it was diagnosed with crankshaft failure. The contact was informed that the crankshaft could be replaced; however, the dealer suggested that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 44,000.

- Tuscaloosa, AL, USA

problem #168

Nov 012024

Sierra 1500

  • miles
I had a complete engine failure that I had to pay out-of-pocket for I really think that this vehicle should-??ve been included in the 2021 and beyond engine recall for 6.2 GMC Sierra-??s. I drove to work one morning Fein after work I turned my vehicle on, and the engine started shaking violently and smoke coming out of my exhaust like I-??ve never seen it before dealer said engine was completely blown and had to be repaired again I paid for this out of my own pocket. It is now coming to my attention that this vehicle is being looked at as an engineering analysis in line with the recall for the 2021 in above GMC Sierra-??s what do I need to do?

- Otawa, IL, USA

problem #167

Jan 022026

Sierra 1500

  • miles
My engine is projecting a ticking sound. Oil consumption is extreme.

- Oviedo , FL, USA

problem #166

Jan 282026

Sierra 1500

  • miles
Engine failure as related to RQ26-001. engine misfires after following recommended maintenance schedule for 6.2L engine. Vehicle is at dealership and available for inspection and dealer is recommending engine replacement. Engine light came on and was brought to GMC dealership same day.

- Lake Helen, FL, USA

problem #165

Jan 262026

Sierra 1500

  • miles
Catastrophic engine failure at 62,445 miles. Dealer state excessive oil in cylinder 7, ring failure. Recommendations; remove and replace engine.

- Dewey, AZ, USA

problem #164

Jun 162025

Sierra 1500

  • miles
I purchased my 2020 gmc sierra 1500 6.2L in September 2024 with 80,000 miles. 9 months later the lifters gave out. Had them replaced and 6 months later, the lifters again were bad and was knocking. They are now replacing the lifters and cam. I am so disappointed that this is happening. I hear that the 2019 and 2020 was not included in this recall! Why not!! If it-??s still doing the same thing and it is the same engine, why isn-??t my truck in this recall" I would like to know why? If it is doing the same thing as the recall, shouldn-??t it be covered by this recall" Best, [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- La Junta, CO, USA

problem #163

Feb 012026

Sierra 1500

  • 87,000 miles
The contact owns a 2020 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed and hauling a boat, the vehicle shook violently and made a loud banging sound. The vehicle failed to accelerate above 40 MPH. The check engine warning light was illuminated. The vehicle was towed to the dealer, and it was determined that there was a misfire in cylinder #6, and that the engine required further inspection. The vehicle was not repaired. The contact related the failure to NHTSA Action Number: EA25007 (Engine, Engine and Engine Cooling). The manufacturer was not made aware of the failure. The failure mileage was approximately 87,000.

- Ocala, FL, USA

problem #162

Oct 032025

Sierra 1500

  • miles
When driving at about 30 mph the truck randomly shut off and would not start or try to start. I was later told the engine crankshaft rod bearings seized.

- Marine City, MI, USA

problem #161

May 082025

Sierra 1500

  • miles
While accelerating on the highway the truck started to vibrate along with a loud tick, CEL came on for misfire and traction control, hard shifting to where I could park at a safe area to wait for a tow. Kids in the car with me 90 plus degree day on the side of the highway.

- Marine City, MI, USA

problem #160

Feb 262025

Sierra 1500

  • miles
Truck started to vibrate and loud tick sound, CEL for misfire and traction control. Hard shifting until I could pull to a safe area to call for a tow. Around 76k miles on the truck when it happened.

- Marine City, MI, USA

problem #159

Oct 132025

Sierra 1500

  • 123,000 miles
The contact owns a 2020 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the engine seized. No warning lights were illuminated. The contact disabled the stop-to-start feature, and the failure ceased. The vehicle was taken to the dealer, and the contact was informed that the repair was not covered under recall. In addition, the contact was informed that the vehicle needed to remain with the dealer for two weeks while performing diagnostic tests on the vehicle. The contact was unable to be without a vehicle for two weeks. The vehicle was the only means of transportation. The contact stated that the failure was a known failure with the vehicle and that the manufacturer needed to repair the vehicle. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The manufacturer was made aware of the failure, and a case was filed. The contact was informed that the repair was not covered under the recall. The contact was advised to take the vehicle to the dealer for a diagnostic test. The failure mileage was approximately 123,000.

- Forest Hill, TX, USA

problem #158

Jan 162026

Sierra 1500

  • miles
The bearings in my engine failed while on the road! The dealer says I need a full engine replacement for $16,000. There were no warnings or indication there was a problem. The vehicle has been maintained perfectly since it-??s purchase.

- Caseyville, IL, USA

problem #157

Jan 142026

Sierra 1500

  • miles
Sudden engine issue. Knocking, power loss, brake and steering warnings. Severely damaged engine. Mechanic says 2 cylinders are irreparably damaged and entire engine must be replaced

- Franklin , TN, USA

problem #156

Jan 112026

Sierra 1500

  • miles
Driving to the lake on the highway towing a trailer, a loud tapping noise started followed by vibration. Engine seems to have lost power during acceleration.

- Newalla, OK, USA

problem #155

Jan 132026

Sierra 1500

  • miles
My 2020 gmc sierra has had poor gas mileage problems i have taken it to gm a few times with them not able to dind anything wrong through diagnostic. A couple years later my horrible gas mileage came back and service ecs and stabilitrack message came back on and disappeared. I spoke to another shop and they advised me its the dfm lifter issues that everyone has been talking about. So the shop performed the well know fix and has fix the issue. A month after now the valve body gave me a p2817 code showing that the solenoid is stuck in the off and was also advised that this is a know issue being addressed. Currently the truck is in the shop. When is enough enough with all the issues across the nation whwn is gm going to make it right

- Mustang, OK, USA

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