Hello I hope someone can help I have 2013 Pete 386 with an Eaton fuller 13 speed. So the vibration happens only when I'm under a load. Usually when I shift from direct to over or vice versa when climbing a hill. So when the vibration starts the RPM needle bounces instead of holding steady RPM. Also if I pull the truck out of gear and Rev the motor to 2200 RPM and put it back in gear the vibration quits every time. I will post a video shortly.