My motor makes a weird harmonic noise when accelerating at around 55-60mph, all the way through to 70-75. It sounds like a ghost or a banshee. Tesla tried to reseat the motor but I was skeptical it would work and it did not. The noise is likely a slip frequency harmonic - around 400Hz. Try an online tone generator to see what 400Hz sounds like Now I am waiting on a new motor but they tore down the part of the assembly line for Roadster motors and are waiting to build it back! Wait time is not known. Anyway... Has anyone else experienced such a harmonic?