Hi, I am new to this forum. Hopefully someone will have some advise for me. Last Tuesday, August 20, 2019, I was driving my wife's 2017 Acadia All Terrian from home to the airport. This is an approximate 2 hour drive. Prior to leaving I checked the diagnostics as usual. The voltage was at 12.7. This seemed low to me but since I am not a vehicle technician or mechanic it did not set off any alarms. While driving I did get a weird feeling that something might be wrong with the steering. After all the vehicle has warnings for everything, I thought. About an hour and 10 minutes into the trip I went to the left lane to avoid something on the interstate. Prior to moving back into the right lane the vehicle suddenly took control and jerked right. Panic sounds came from the back seat and my wife asked me what happened? All I could say was "I have no idea". I slowed down considerably for the next 45 minutes trying to figure out if it was something I had done. The steering in this vehicle is quite sensitive which makes it easy to drive. Once at the hotel I considered my options. The next morning I called the dealership and asked them about what could have happened and if they had heard of an incident like this before. My service advisor also asked if it had happened since to which I replied "No". They recommended on my way back home I stop in and let them look at it. They also said if I was concerned with driving the vehicle to have it checked out by a local GMC dealership (We were an hour away). I chose to take it to the folks I know and trust so nursed the vehicle back to the dealership. After checking the Acadia the technician stated that the voltage had dropped to low and it was either the battery or the alternator. Imagine my surprise when I asked him if this could cause the Acadia to suddenly take control of the steering...his reply was yes. I then asked him why there was no warning on the idiot panel (that's what I call it) and he stated the warning for this incident was below the threshold of it happening. What????? When I asked the service writer about it she stated that it was not within the control of the dealership but I could contact GMC which I did. The problem has been escalated and I am working with an advisor. As he stated Safety is one of GMC's biggest concerns. When I asked him to put this, as well as the incident into an email and send it to me his answer was no he could not. At that point I stated that I may have to pursue other avenues. His reply was if you are going to contact a lawyer he could not longer talk to me. I would have to be referred to the legal department. I explained that was not my intent. But I also emphasized that this was very concerning to me. My wife drives this vehicle and as she said, after the incident, she would have panicked and had no idea what could have happened. The week prior she had taken the same route we were on at the time of the phantom vehicle take over. My concern is if I had been passing a Truck or another Vehicle this situation could have had major consequences. I will keep you posted as to what GMC's fixes are. I am just posting to let you know that stuff happens and some of this stuff could be deadly. I am hoping the company will stick to it's policy of safety first and resolve the problem. I am also very concerned with my wife ever taking this vehicle out of town again.