2020 GMC SIERRA 1500 Complaints

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

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.

Vehicle is shifting hard when switching gears. Typical with the recall and the valve body being the issue. Dealership is saying it is not covered by recall.

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.

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

The brakes suddenly activate and cause the vehicle to rapidly stop with no warning of any kind and without any braking action being taken by the driver. Then, the brakes do not release and the vehicle cannot be moved as the brakes remain on. Turning the engine off and then restarting it or shifting to other gears does not release the brakes. The vehicle remains immobile and cannot be driven. After a few hours have passed, like overnight, the brakes release and the vehicle can started and driven just as if nothing had happened. A message briefly appears on the vehicle information screen each time this inadvertent braking occurs. It reads, “Brake Failure System”. These brake lockdowns occurred when driving on streets and in the driveway. No accident resulted but could have easily occurred. This is dangerous for a driver and occupants of a vehicle with this safety flaw as well as for other people and vehicles in the vicinity. This has happened five times. The last two instances resulted in the vehicle being loaded onto a tow truck and taken to a dealer of the vehicle’s manufacture. Thus far the dealership has not found what may be causing this intermittent braking problem.

The contact owns a 2020 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle unexpectedly sputtered. There was no warning light illuminated. The vehicle was taken to the dealer, where it was diagnosed with torque converter failure. The dealer determined that the torque converter needed to be replaced. The vehicle was repaired. The contact later stated that while driving at an undisclosed speed, the vehicle unexpectedly went into LIMP Mode. There was no warning light illuminated. On several occasions, the vehicle unexpectedly downshifted and lunged forward while stopped at a traffic light. There was no warning light illuminated during the failure. The dealer was contacted. The vehicle 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 97,000.

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.

On Friday, January 30, 2026 while driving our 2020 GMC Sierra 1500, we experienced sudden loss of power and the motor making a faint rattling noise. The motor soon after began making a horrible sound - - it was obvious something was very wrong. This vehicle only had 31,995 miles on it at the of the issue. We had the truck towed to the dealer the following day for evaluation. Upon inspection, it was determined that the #5 lifter had collapsed and the left bank of lifters needed to be replaced at an estimated cost of $4500. There were no warning lamps or alerts on our app for over 24 hours. Once at the dealer, we explained to the service advisor that our research concluded that GM is fully aware of these issues and that they are under investigation for possible recall. Our service advisor then made a call to GM who agreed to cover this repair under warranty (which we appreciate and feel was the right thing to do). However, after additional research, we are concerned that the right bank of lifters will fail next, or even worse, catastrophic engine failure that GM will refuse to cover. It is our understanding that NTSB is aware of these issues and is in the process of conducting an investigation. I would like to have our issue added to the investigation.

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?