this incident happen last saturday when i drove my e46 325i to genting to attend some function, as i almost reached the slope i accelerated harder to climb. after three hill climb i reached parking lot, as i was going to changing gear to reverse my car..some rough sound came out from the gear box------>(like this..."kuk") and my car was like moving a bit eventhough i have stepped on the brake and i do this again simultaneously from reverse gear to "D" gear the sound still there.so u jus left the car in parking lot and the nex day while i was preparing to come back the car become normal again, which means it doesnt have the rough sound again. May i ask what actually has happen to my car????is only 3 years old 
