Presently there is a gear whine noise issue in a vehicle transmission. Our NVH team captured the noise signal using a microphone and then did an FFT of the signal and gave us a frequency plot. What exactly can I take out of it? Can I assume every harmonic belongs to a noise generated by a gear having the same meshing frequency? Then, what are those harmonics which don't match with any gear order? An irrelevant question - Does excess PCD runout of a gear cause whine? How to prove if that is the major cause?