2020 GMC Sierra 1500 Power Train

The AFM/DFM system in these trucks are making the engines and transmissions go out around 70k miles. The lifters fail right around the same time factory warranty runs out then your left with a 6 thousand dollar bill to have it fixed. I hope this becomes a recall because numerous people I talk to are getting rid of they're gmcs and chevys and going elsewhere.

The transmission went at 67,000 miles and posed a safety issue when my husband was driving & suddenly couldn't drive above 1st gear. Vehicle is at the GM dealer and has been for weeks, but there have been so many issues with the transmissions of this year, make & model, that the transmissions are on back order and we are told it can be MONTHS before they get one in. The dealer already has another one that has been waiting for once since April. We know of others with this same issue on this make/model/yr, as well as engine issues, but yet there are NO recalls for this issue. The only warning that came on was when the issue occurred- no prior warning or indications. GM is involved but make no comment on why there isn't a recall for an obvious known issue.

Has happened three times. 1st and 2nd time driving down road towing trailer, rear wheels locked up for 12-15’ while driving 50-55mph. I had thought it was my trailer axel. Happened twice within 6 miles. 3rd time was 1 month later. Rear Wheels locked up driving on interstate at 70-75 mph. I estimate that i traveled 1,800 miles between the 2nd and third incident. Vehicle is at the dealership getting inspected for repairs No warning lamps before, almost every warning light came on after incident If this happened on a wet, ice, snow or dirt road this could have caused a serious accident. It would also be bad in a curve. Dealer took for road test but did not have any luck recreating the issue. They checked the differential oil And it didn't have any heavy metals. They are going to take the differential apart to inspect it to verify. They checked my battery and said it needed to be replaced. Also a wheel speed sensor needed to be replaced.

Bearing in transmission failed at 75000 miles. Took to dealership and they said truck needs new transmission. Truck makes rattling noise in transmission pan. Dealer said that oil was full of metal shavings. Dealer also said that this was second truck in 2 weeks with same issue. No warning lights or check engine lights came on. Dealer advised that the transmission could fail and to park it until I can pay $6000 for transmission replacement. Dealer heard rattling and confirmed metal shavings. Transmission failure could result in traffic hazard or accident if transmission loses all drive ability.

Consistent issues with my truck. It is a 2020 GMC Sierra 1500 vin: [XXX]. In April 2022, my truck started to exhibit concerning issues. I was worried about driving home from work and called the dealership I bought the truck at. They recommended that I take it to the the service center in Frankfort, KY where I work. I drove the truck directly to Neil Huffman GMC. They declared the truck unsafe for me to drive. They set up rental car for me to use and I left the truck at the service center. They initially said it was the torque converter. Over the course of two months they kept finding more issues. Repairs were completed at Neil Huffman GMC service center located in Frankfort, KY. My truck still has the following issues.. 1. Ringing sound 2. Grinding or clunking noises 3. Loud noise when I press the gas pedal 4. Delayed shifting and hard shifting problem I drive a hour back and forth to work everyday and don’t want the truck to have issues on the interstate. Driving with a bad torque converter is unsafe since it causes sudden stoppages and significant speed fluctuations. Worn or slipping transmissions have many warning signs. A damaged transmission creates a dangerous situation for me and for other drivers. I had an appointment at Adams GMC in Richmond, KY on September 1st. They said they couldn’t hear anything and no services were conducted. Neil Huffman GMC service department said they replaced basically the entire transmission. I don’t understand why there would be issues still. [XXX] INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).

My 2020 Sierra SLT always hesitates or stutters upon take off only on the very first start of the day every day. It appears to be a transmission gear issue or perhaps air/fuel issue. I also have had several different issues with my infotainment system. It screen changes from one screen to another on its own occasionally and it also has a very loud pop when I turn off my iphone Xr from the trucks sound system as if it will crack my speakers. I have taken it in to two separate Cavendar GMC dealerships in San Antonio on 3 different occasions and they claim it does not do either. This cannot be the case as it does it for me every single day since I bought it from the showroom floor. They have said they have updated or reprogrammed both systems but I still have both issues. I am about to lose warranty coverage and I am afraid this will never be addressed. I am taking it in 1 last time. I will never buy another GM product!

The contact owns a 2020 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle shuddered. The vehicle was taken to the dealer however, the mechanic could not duplicate the failure. The vehicle was then taken to Gilland Chevrolet GMC (3071 N US Hwy 231, Ozark, AL 36360) where the contact was informed that the vehicle already had new transmission fluid filled in the transmission. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 42,000.

TL* THE CONTACT OWNS A 2020 GMC SIERRA 1500. THE CONTACT STATED THAT UPON EXITING THE VEHICLE, HE NOTICED THAT THE VEHICLE WAS LEAKING AN UNKNOWN FLUID. THERE WAS NO WARNING LIGHT ILLUMINATED. THE VEHICLE WAS TAKEN TO SIMPSON BUICK GMC OF BUENA PARK (6600 AUTO CENTER DR, BUENA PARK, CA 90621) WHERE IT WAS DIAGNOSED WITH THE TORQUE CONVERTER NEEDING TO BE REPLACED. THE VEHICLE WAS REPAIRED HOWEVER, THE FAILURE RECURRED. THE MANUFACTURER WAS NOT INFORMED OF THE FAILURE. THE FAILURE MILEAGE WAS APPROXIMATELY 11,000. THE VIN WAS UNAVAILABLE.

TRANSMISSION KICKS WHEN COMING TO A COMPLETE STOP.

THE TRUCK RANDOMLY GETS STUCK IN PARK. CANNOT PUT IT INTO DRIVE, NEUTRAL OR REVERSE. THE CAR HAS BEEN AT THE DEALERSHIP SINCE JANUARY 27, 2020. GMC WONT SEND THEM THE PART, THE DEALSHIP BELIEVES IT MUST BE A PROBLEM WITH THE PART AND THEY ARE TRYING TO FIX OR REDESIGN THE PART BEFORE ITS SENT OUT. ALSO I WAS TOLD BY MY DEALERSHIP ANOTHER 2020 AT4 CAME IN WITH THE SAME PROBLEM. IT WAS TOWED TO THEM.