8 speed transmission jerking, the torque convertor has been replaced 1 time already and having same issues as before. This time while in parking lot at store, was pulling into parking space, truck lundge forward during hard downshift hitting cart of person walking in front of truck. No damage and luckly barely hit the cart and not the person. I have also had the truck lunge forward when parking in my garage and hitting the garage wall in front. My truck is back at dealer again after hitting the cart in the parking lot. The 8 speed transmission issue from GM is a safety issue. My truck has already had first torque converter replaced and now having same issue with the new torque convertor