My 1979 F100 FWD LWB has over the past3 yearsdeveloped an extreme transmission viabration type noise in top gear under light throttle conditions, to the point that the vehicle has become completelyundriveable and unreliable.

The transmission and clutch assembly has been removed and replaced with new parts approx6 occasions, each time after an approx distrance of 2-3,000 miles, each time to no avail

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