2020 GMC Yukon Complaint Log

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??

I had an incident in my 2020 GMC Yukon, where the forward collision crash alert went off and there was total loss of brakes. The brake pedal went to the floor. After the crash alert ended, the brakes returned. This happened on the highway and could have turned into a disastrous event. The dealership has been unable to diagnose or recreate this issue. They claim they did not find anything and the vehicle is safe to drive. I have turned off the collision detection system in the meantime. I feel strongly that this is a software issue that needs addressed. GM has replied that they support the dealership but if I want a second opinion I can go to another dealership for input.

Transmission started slipping a little and then literally stopped working all with in an hour. And was doa in the parking lot.

MISFIRE ON #6 CYLINDER. DIAGNOSIS REVEALED THE INTAKE VALVE IS NOT OPENING DUE TO COLLAPSED VALVE LIFTER. No message prior to engine light coming on and car shaking after driving back from the store (speed less than 45 MPH).

The contact owns a 2020 GMC Yukon. The contact stated that while driving at an undisclosed speed, the check engine warning light was illuminated. The vehicle was taken to the residence, the contact exited the vehicle and discovered white smoke coming from the exhaust and started to smell coolant and then discovered that the coolant level was low. The contact added coolant, and the check engine warning light was no longer illuminated. The contact’s husband and son, who were knowledgeable about vehicles, had self-diagnosed the vehicle and determined that the head gasket or the lifters might need to be replaced. The contact stated that the failure had occurred on several occasions and the contact consistently added coolant; however, the check engine warning light was illuminated every 300 miles once again. The contact researched and was made aware of an unknown NHTSA Campaign Number; however, the VIN was not included. The vehicle was taken to an independent mechanic, where it was diagnosed and determined that there was an unknown internal issue with the engine that was possibly associated with coolant leaking into the engine. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 52,000.

total engine failure with 90,000 miles on the car.

I purchased a new 2020 GMC Yukon in May of 2020. Between May 2020 and November 2025 the vehicle was routinely serviced on or before the due date recommend by the manufacturer. I had not experienced issues with the vehicle until November 2020 when the check engine light abruptly appeared and the vehicle began driving very rough. I immediately took the vehicle to the local mechanic who identified two codes (P0300 and P050D) related to the engine issues. The vehicle was towed to the dealership due to the fact that I was instructed it was unsafe to drive long distances without additional diagnostics. The dealership disassembled the engine and found coolant leaking into cylinder six. There were no cracks or otherwise clear means of entry for the coolant into the engine. The dealership instructed us that we would need a complete engine replacement. Upon further research of this issue, it was uncovered that a Service Bulletin had been issued for this very issue. The reference number is 20-NA-166, updated March 2024.

My vehicle went from driving perfectly to startling and not going pass 45 in a matter of two days. I was getting all maintenance done at dealer always on time had just service it. When all of a sudden it started making a jerking/ skipping feel as if I was accelerating too hard. Took it to get checked and the code that came up was (TCC)torque converter clutch. I spent 6000 to rebuild the transmission and kno the engine has a tap tap noise. Once again I took it in and now it’s the lifters in the engine. No warning light have ever popped up

We purchased the vehicle used in April 2025 with 79,851 miles. All service records were documented via Carfax. Vehicle was in impeccable condition. We drove it for approx. 8,000 miles until July 10, 2025, when a loud knocking sound started coming from the engine - approx. mileage 87,600. We drove the vehicle home 350 miles. The knocking sound continued and got slightly worse. We drove it to the nearest dealer (30 miles) and the mechanic said it sounded like a camshaft problem. However, they could not get it in for over 60 days. We drove to another dealer (45 miles). The mechanic said he thought the entire engine was bad. We left the vehicle there and about a week later they were able to confirm that it was TOTAL BEARING FAILURE. Mileage 88,054. We were told that a new engine was needed as well as a radiator and new oil lines, etc. Total estimate $18,000. They also said there was no timeline they could guarantee because of the current GM recall. Of particular note and concern...at no time did the 'check engine' light come on or any other warning system activate. Both mechanics were genuinely perplexed at this. The repairs were ordered and the vehicle is now repaired. However, GM has not confirmed a cost share for the repair billing and we are now almost 60 days since they received the paperwork from the dealer so we still do not have our vehicle back. We filed a complaint with GM and a case number was assigned so they are fully aware of the issue as is the dealer who did the repair.

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.

While driving to Lake Placid, NY, I experienced sudden loss of propulsion as I was driving approximately 60 mph. I was able to brake and pull over to the shoulder. I was not able to restart the vehicle - engine was dead. We were flat bed towed to a garage in Lake Placid where it was confirmed that the engine was inoperable. The vehicle is now at. GM dealer in Potsdam, NY. I believe this engine should be part of the recall!!

Hello, I’m calling about the GM transmission recall recently announced in March 2025 affecting 2020 Yukon vehicles. My Yukon experienced what I believe is the exact same issue described in the recall. Our vehicle lost forward gears and almost caused a crash. A certified mechanic confirmed the transmission fluid was burnt and full of clutch material, with internal transmission damage. We are asking for this to be handled under the recall, as the issue directly matches GM’s known safety defect. We need this resolved immediately — the vehicle is unsafe to drive and the failure happened before we even knew about the recall. Our GMC Mechanic stated the following : Needs immediate attention Recommended service Transmission: test drove verified no forward gears after 3 minutes of driving. fluid brown and burnt full of clutch material. internal damage to transmission. A transmission flush is a process that makes it possible to clear the old transmission fluid from the vehicle's transmission. This process also helps to remove residue of older transmission fluid from the converters, coolers, and cooler lines that often are part of the design for the transmission.

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 .

I purchased my 2020 Yukon Denali on July 8, 2024 from Classic Buick GMC in Painesville, Ohio. The check engine light started going on and off a few months after purchasing the vehicle. When I called a mechanic he stated that I should wait until the light is on and then bring in the vehicle. In early May 2025, I took my vehicle to Mike’s Automotive in Middlefield, Ohio after the check engine light began coming on during extended drives (approximately five hours or more). The shop ran a diagnostic scan and advised that the oil pump needed to be replaced. Seeking another opinion, on May 14, 2025, I brought my vehicle to Classic Buick GMC Service, the dealership where I purchased my GMC Yukon. After diagnosing the vehicle, they advised that the check engine light was related to an Engine Oil Pressure Control Solenoid stuck in the off position (P06DD). This fix would cost $3,584. This fix would require the oil pump to be replaced as indicated by the previous repair shop. On May 29, 2025, I took the vehicle to Avenue Auto Clinic in Painesville, OH, where the oil pressure valve and sensors were replaced. The mechanic also advised that I change the oil every 3,000 miles, use OEM oil filters, and thicker oil. He also advised me to check the oil every 1,000 oil and add as needed. I do have to add oil approximately every 1,500 miles and I change the oil every 3,000 miles. I am concerned that my vehicle has the same engine-related defect as the Yukon engines currently under recall. Multiple mechanics have informed me that my vehicle is equipped with the same engine as those affected by the recall. I am requesting that my vehicle be added to the recall. Yes, my vehicle is available for inspection.

The contact owns a 2020 GMC Yukon. The contact stated that while refueling the vehicle, the fuel filler neck was not allowing fuel to flow into the tank. There were no warning lights illuminated. The vehicle was taken to the dealer, who diagnosed a failure with the fuel filler neck. The contact was informed that the fuel tank filler assembly needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure but provided no assistance. The failure mileage was approximately 42,000.

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

Ambient temp was 100 degrees for reference. Had been driving about 5 hours. Went to stop and had no power assist for brakes. This continued for at least 20 miles. Stopped and confirmed vac hose was connected. I tried to remove vac hose to check for vac at booster but was afraid I might break the part. Electrical plug at vac hose booster connection was secure. Continued driving and it began to work again. Condition: brake pedal took considerable foot pressure to apply brakes. Zero power brake assist was available. My qualifications; a past ASE master teck.

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.

TL* THE CONTACT'S WIFE OWNS A 2020 GMC YUKON EQUIPPED WITH CONTINENTAL TIRES, TIRE LINE: CROSSCONTACT LX SPORT, TIRE SIZE 245/50/R20. THE CONTACT STATED WHILE DRIVING 65 MPH, THE DRIVER'S SIDE FRONT TIRE EXPERIENCED A BLOWOUT. THE VEHICLE WAS TOWED TO DAVID BALES BUICK GMC (1327 JACKSBORO PIKE, LAFOLLETTE, TN 37766, 423) 562-8431) WHERE THE VEHICLE WAS STILL AWAITING A DIAGNOSTIC TEST. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS NOT INFORMED OF THE FAILURE. THE FAILURE MILEAGE WAS APPROXIMATELY 14,900.

TL* THE CONTACT OWNS A 2020 GMC YUKON. THE CONTACT STATED WHILE REVERSING, THE BACK OVER PREVENTION CAMERA WAS OBSTRUCTED AND THE CONTACT WAS UNABLE TO SEE A PROPER IMAGE WHILE THE VEHICLE WAS IN REVERSE. THE CONTACT STATED NO WARNING LIGHT WAS ILLUMINATED. THE VEHICLE WAS TAKEN TO THE LOCAL DEALER SHELTON BUICK GMC, INC. (855 S. ROCHESTER RD, ROCHESTER HILLS, MI 48307, (248) 266-2156) TO BE DIAGNOSED. THE CONTACT WAS INFORMED THAT THE CAMERA FUNCTIONED AS DESIGNED. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS INFORMED OF THE FAILURE. THE FAILURE MILEAGE WAS APPROXIMATELY 6,000.

THE RENTED 2020 TAHOE WAS STATIONARY. A PASSENGER SITTING IN THE LEFT THIRD ROW SEAT BECAME STUCK IN THE SEAT BELT. SHE WAS UNABLE TO OPEN THE SEATBELT CLASP AS IT GOT STUCK AND FAILED TO UNLATCH. THE MORE THE PASSENGER STRUGGLED TO UNLATCH THE SEATBELT, THE PROGRESSIVELY TIGHTER IT BECAME. PASSENGER COULD NOT DISENGAGE THE SEATBELT CLASP BY PRESSING THE TINY RED BUTTON. THREE OTHER PASSENGERS TRIED TO RELEASE THE SEATBELT AND COULD NOT. PASSENGER WAS TRAPPED WITH TIGHT SEAT BELT HOLDING HER IN. OTHER PASSENGERS CALLED EMERGENCY PERSONNEL WHO ALSO COULD NOT RELEASE THE EVER TIGHTENING SEAT BELT. PASSENGER WAS RELEASED WHEN THE RANGER CUT THE SEAT BELT WITH A SEATBELT CUTTING EMERGENCY TOOL. IT WAS A VERY SCARY AND DANGEROUS EXPERIENCE. LATER, SOME OF OUR GUESTS FIGURED OUT THAT YOU HAVE TO PRESS THE TINY RED BUTTON ON THE LEFT LATCH WITH A PIECE OF THE RIGHT BUCKLE. A PASSENGER SHOULD BE ABLE TO RELEASE THE SEATBELT BY DEPRESSING THE RED BUTTON. A PASSENGER CANNOT EVEN REACH THE BUTTON FROM THE SEATED POSITION AS THE BUTTON IS TINY AND CANNOT ACCOMMODATE AN ADULT FINGER TO DEPRESS IT. THIS IS THE WORST EXAMPLE OF ENGINEERING I HAVE EVER EXPERIENCED. I AM FRANKLY AMAZED THAT THIS DESIGN PASSED ANY SAFETY TESTS. PLEASE ADDRESS THE ISSUE BEFORE SOMEONE IS HURT OR KILLED BY BEING TRAPPED IN THE VEHICLE AND UNABLE TO ESCAPE. *TR

LINE KEEP ASSIST NOT WORKING PROPERLY. ASSISTANCE SYSTEMS FOR PARKING OR BACKING NOT WOKING PROPERLY. LANE CHANGE ALERT NOT WORKING PROPERLY

TRANSMISSIONS ISSUES. Not transitioning/ shifting into gears smoothly or at all. When it does transition/shift it is rough and harsh. When my car transitions to a lower gear then it will not transition back up to a higher gear causing my vehicle to drop speed significantly that I am a safety hazard on the road. Example: when it shifts to a gear high enough that the vehicle can reach 40 mph and there is a need to decelerate it does but once it drop to lower gears it cannot engage again to a higher gear leaving me stuck going at most 10 mph with not opportunity to excelerate in traffic to a higher speed. The transmission control module (TCM) software was updated with no improvement.