[SCW001]

My midstates cobra utilizes a Ford 4 speed toploader transmission and a Ford 9" rearend. I notice a harmonic hum
at relatively low engine rpms (1500 - 2000) when the throttle is slightly depressed, like when you are easily cruising on level road.
As soon as you let off the throttle completely or increase the throttle the hum dissappears. It seems to depend on throttle position and the lack of any real load on the drivetrain by the engine or the road. Any suggestions on correcting this hum would be greatly appreciated.

Thanks Steve