When I shift from first to second I hear a thunk which is obviously coming from either the transmission or engine. Its in the center of the car just forward of the shifter. Under normal shifting there is no thunk. The faster I let the clutch out the louder the sound is. So I'm guessing engine or transmission mounts. Is this normal? The car was in an accident which took a front end impact on the passenger side. If it's kind of a normal thing how can I fix this?