2021 Chevrolet Silverado Trail Boss with transmission valve body problem. Truck nearly stalled while driving and towing my boat then a huge clunk in the transmission. The truck then rapidly accelerated, down shifted, brief wheel lock up and I was nearly sent in to the ditch with my trailer now swaying behind me. The entire situation felt extremely unsafe and dangerous to both me and oncoming traffic. The check engine light was then on and the truck went in to limp mode. The truck would also no longer go into reverse. I first brought the truck in in October. They finally diagnosied the problem on November 4th, 2024. It is now February 14, 2025 and GM can still not provide me and ETA for the part or for repair. I’ve opened a service ticket with GM and asked for a buyback as I do not feel safe driving this vehicle any longer. I still do not have resolution with GM or my local dealership.