NHTSA Complaint #11585881 — 2020 GMC SIERRA 3500

I was driving approximately 60mph pulling a trailer when the back tires locked up for approximately 2 seconds. This happened 3 times within 30 minutes. I've taken it to the GM repair shop. They have seen this happen to 3 or 4 vehicles. Due to not being able to replicate the fault it has been difficult to diagnose. They are going to replace the transmission valve body hoping that will take care of the issue. This is extremely dangerous to everyone on the road when this happens. There are many forums out there that I've read and have been close to deadly accidents involving cars, trucks, RV's, and semis as they've ran off the roads. This seems to be something worth looking into and ensuring GM puts out a recall for. In my case, I am going through an extended warrant for my 2020 3500 with 112,000 miles. The warranty company wants the GM technician to replicate the fault... which isn't possible without hooking up a trailer... also very dangerous which I refuse to do until the issue if resolved. In any case, I will have to hook up a trailer once the part is replaced... praying that it won't happen again.