i have a 2020 2500HD duramax, while Towing my Camper roughly 12-13K, my Truck start a hard jolt while cruising down the highway, has anyone else felt this? started out doing it above 70, slowed down to 65 after a little while start at 65 then down to 60, 55 and so forth, never during accelleration or while slowing down just while cruising, faster the speed harder it hits, feels like something wants to lock up, thought maybe the camper but unplugged it and still the same issue. it's at the shop now but the only thing they are thinking are possibly a ECM/TCM update.