My 2010 X3 (standard transmission) started flashing the 4x4 in yellow and the car would start bucking. It only last a few seconds each time it happens. This happens occasionally when in first gear and pulling away from a traffic light. At first it threw a lot of codes and my mechanic replaced the transfer case motor and it was fine for a few weeks and it started again. But only very occasionally. Has anyone else had this? Can you tell me what i need to tell the mechanic to check? It is no longer throwing codes so he doesn’t see what the issue is and since it only happens occasionally i can’t get it to do it when we are driving it together