There are 10 owner-reported powertrain & transmission complaints for the 2020 GMC Yukonin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
The 2020 Yukon started to have serious loss of speed and decelerating issue when the vehicle would slow down and down shift to a lower gear. The issue with this is that once it downshifted it woul not engage in a gear again and leave me stranded on the road. I had to turn off the car and restart it for it to reengage in a gear enough to get it moving again and sometimes I had to try more than once to get it moving once it no longer wanted to engage in a gear. So in the 10 mile drive, I was left stranded at least 15 times. Each time I had to restart and restart again for the vehicle to engage in a lower gear. Once moving, it would sometimes it would engage in a higher gear and sometimes it would not. Thank goodness I wasn't traveling on the highway when this happened. Beware to anyone if this was to happen on the highway while in the middle lane while in traffic. And the check engine light never turned on and thus no code to help detect the issue. Took it the day before to have it looked at and was told nothing was wrong with it since there was a code and they could not duplicate the issue I described. WHAT?? They reset some transmission computer setting but it only made it worse by the next day. Now this 6 yr on 2020 GM Yukon is at the dealership service department requiring a new transmission for 7200. Said that the transmission fluid was showing particles of stuff and color was 'burnt', I think. Transmission fluid was changed at it's regular check up time so that didn't cause the issue and nor should it have bits and pieces in it and discolored. Is there any recourse to GM and it's crappy transmissions??
Transmission started slipping a little and then literally stopped working all with in an hour. And was doa in the parking lot.
The contact owns a 2020 GMC Yukon. The contact stated that while driving at an undisclosed speed, the vehicle inadvertently lost motive power, prompting the contact to pull over to the shoulder of the roadway. The contact became aware that the vehicle continued to move forward while shifted into Park, Neutral, or Reverse. The contact stated that the message "Transmission Overheating" was then illuminated. No warning lights were illuminated. The vehicle was not taken to the dealer or an independent mechanic. The vehicle was not repaired. The manufacturer was notified of the failure, a case was opened, and the contact was referred to the NHTSA Hotline for assistance. The failure mileage was 119,000. The contact declined to provide the VIN.
The contact's wife owns a 2020 GMC Yukon. The contact stated the vehicle was taken to an independent mechanic for a tune up. The contact stated that upon picking up the vehicle and driving, the transmission was slipping in and out of gear. Additionally, the contact stated while at a complete stop and depressing the accelerator pedal, the engine revved; however, the vehicle hesitated to respond, and the vehicle jerked while responding. The contact stated that the vehicle slowly picked up speed, and the transmission was slipping in and out of gear. There was no warning light illuminated. The contact stated that his wife had noticed that the vehicle made an abnormal sound while driving. The vehicle was taken to the dealer, where it was diagnosed that the torque converter had failed. The dealer determined that the transmission needed to be replaced. The vehicle was repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 107,267.
Vehicle started jumping and switched into 4WD while reversing. There was no inclement weather or slipping to prompt this. Service 4WD warning had been showing intermittently for a week or two and service appointment had been scheduled. At service appointment, confirmed that 4WD switch was faulty and needed to be replaced.
6L80 transmission complete failure while driving. Vehicle started shacking then check engine light came on .
Shortly after the warranty expired my torque converter went out and damaged the transmission. After speaking with several transmission shops this is a known problem with this vehicle! The torque converter and transmission are poorly made, and no matter if you get all of your services this will still happen to you! This should be a recall on this vehicle. Less than 4 years old and I am having to spend over $5,000 to replace a transmission. The vehicle just hit 100,000 miles. If this is a known issue with this vehicle why has it not been recalled? The dealership tried to tell me I just needed battery cables replaced. I decided to get a second and third opinion and as I suspected the transmission is gone. There were NO warning lights, the car just suddenly started not wanting to change gears while driving. At the red light it jumped and wouldn’t move which made the car behind me almost hit me. There were no other symptoms until the gears started not wanting to change. No noises, smells, or any indication that something was wrong. The vehicle is now at a transmission shop awaiting repair. This needs to be a recall if this is a known issue.
2020 GMC Yukon transmission failed at 103.000 miles
Transmission slipping and damage
The transmission is out. Prior to it going out, I experienced loss of power, gear slipping, shuttering and not being able to go among other things. This is very dangerous and can cause serious accidents to occur. This should not be happening on such an expensive and newer vehicle.
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026