2020 GMC Terrain power train problems

“While driving my 2020 GMC Terrain, I experienced a sudden loss of normal braking assistance. I had been traveling on the highway and exited onto a main road. As I approached a red traffic light at approximately 50 mph and attempted to brake, the vehicle would not stop normally. I was unable to stop for the red light and went through the intersection before I was able to safely get the vehicle off the roadway. Fortunately, there was no vehicle directly in front of me and I was able to make it through the intersection before any other cars, so no collision occurred. The vehicle was subsequently inspected and diagnosed by a GMC dealership. A diagnostic scan performed after the incident showed code P0556 for the brake booster pressure sensor circuit range/performance. The GMC dealership later diagnosed problems involving the vacuum pump, exhaust camshaft, and timing components and recommended replacement of the vacuum pump, exhaust camshaft, timing components, and related parts.” The sudden loss of braking assistance created a serious safety hazard and could have resulted in a collision, serious injury, or death. The vehicle is currently available for inspection.”

“Having the start stop issue on my terrain and recently over the last few months, it has been using oil everything that sounds exactly like the recall but mine is not included. My start stop is not working and I have to get him since it had only 60,000 miles on it years ago, but nothing was done.”

“Because of the intentional failure of GMC and there promise of “We are Professional Grade”, I almost got plowed down by a semi when the car began to quit on the highway going 60. After pulling into the next driveway, which happened to be a Parker’s Kitchen, and ending up on the curb spot, thanking God I wasn’t dead, I sat there for a moment wondering what just happened. As I went to restart the car, it wasn’t having any of it. 40,000 miles, not professional grade GMC, circus grade. Towed it to my home, figuring it has to be something minor and a diy fix. Bought the hyper-tough code reader delivered by Walmart and it delivered professional grade results: U18A2, P1787 and P187E. I am beyond pissed. I could have died due to your intentional negligence in manufacturing. I have a car that will not start, with payments. I have searched the internet and found your “save ourselves plan” and let’s do a voluntary recall starting with 2021 on the same failed parts I am dealing with at the moment. Thanks GMC, who is the ringleader of your circus?”

“The contact owns a 2020 GMC Terrain. The contact stated that while driving 35 MPH and depressing the accelerator pedal while driving uphill or making a left or right turn, the tires were skipping, and there was a clicking and whining sound coming from the front of the vehicle. There was no warning light illuminated. The contact stated that a friend test-drove the vehicle and informed that the vehicle had experienced transmission failure. Neither the independent mechanic nor the dealer was contacted. The vehicle was not taken to the dealer or an independent mechanic to be diagnosed or repaired. The contact related the failure to NHTSA Campaign Number: 20V668000 (POWER TRAIN); however, the VIN was not included in the recall. The manufacturer was notified of the failure and informed the contact that the VIN was not included in the recall. The failure mileage was 104,000.”

“The intercooler has been a document problem on GMC Terrains for awhile now. I had my intercooler replaced and now less than 10 months it is having the same problem. The vehicle will go into reduced power mode which would be a safety hazard because it will also stall sometimes when it is having performance issues. That could lead to someone colliding into me if it suddenly stops when someone is behind me. I believe this part should be recalled and fixed for free.”

“The contact owns a 2020 GMC Terrain. The contact stated that while making a turn, the transmission shifted into neutral and briefly lost motive power and stalled. No warning lights were illuminated. The contact was able to restart the vehicle; however, the vehicle failed to function while shifting to drive(D) or reverse(R). The contact opened and closed the door to see if the vehicle would reboot. After several attempts, the vehicle returned to normal functionality. The contact stated that on a separate occasion, the transmission was leaking transmission fluid. The transmission was constantly slipping. The check engine warning light was intermittently illuminated. The vehicle was taken to the dealer, where it was diagnosed that the START/STOP accumulator in the cap was missing bolts, which caused the transmission to fail. An unknown code was provided to the contact. The vehicle was not repaired due to the cost. The vehicle was taken to various independent mechanics who confirmed that the transmission had failed. The manufacturer was made aware of the failure. The failure mileage was approximately 94,000.”