10.0

really awful
Crashes / Fires:
0 / 1
Injuries / Deaths:
0 / 0
Average Mileage:
4,750 miles

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problem #4

May 122023

Sierra 3500

  • miles
Engine Coolant Low error constantly appears. GM Service provider states that engine coolant level is fine, but sensor may be defective.

- Portsmouth, NH, USA

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problem #3

Nov 252024

Sierra 3500

  • 19,000 miles
The contact owns a 2020 GMC Sierra 3500. The contact stated while driving approximately 60 MPH, the vehicle jerked, lost motive power, and almost stopped unintendedly. There was no warning light illuminated. The contact was able to pull into a parking lot, where the vehicle shut off. The contact stated that while attempting to restart the vehicle, the diagnostic trouble code: P129F was displayed, and the vehicle failed to restart. The vehicle was towed to the residence. The local dealer was contacted and advised the contact that the failure might be related to the fuel pump control module and that the part was on backorder. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The failure mileage was approximately 19,000.

- Kailua-Kona, HI, USA

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problem #2

Nov 132022

Sierra 3500

  • miles
Plugged in engine block heater and the car erupted in flames. Total loss.

- Lawton, OK, USA

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problem #1

Jul 072020

Sierra 3500 4WD 8-cyl Diesel

  • Automatic transmission
  • miles
The computer lights up the dash reducing power and turning off power to trailer brakes. This has almost caused an accident on several occasions. It happens a couple of times per trips. This vehicle has been in the shop a couple of times per month since it was put into service. Glenn Polk Chevrolet has worked on it each time and the problem is still there. This truck has also had several injector issues. There is an open case with this vehicle with General Motors with no resolution. I have filled out forms on each of my 2020 GMC's 3500's.

- Irving, TX, USA

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