75 mph :

75 * 5280/3600=110 ft/sec

110/7.3=15.068 rev per sec

40/15=2.667

Should not be in the bearing nor CV axle. I would look into drive train.

4.1:1 differential. 15.068*4.1=61.779 hz so that shouldn't be it either.

Do the frequency test at a different speed. I have a feeling something is causing a harmonic but weird when not at a ratio of the wheel RPM.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)