Does the noise get bad when decelerating in any gear? If so, maybe pull the differential cover and take a look at the differential. I would bet if there are metal flakes in the oil, then you've found your issue.

Rebuilding a differential isn't for the faint of heart. But transmissions are basically inspecting and replacing parts (some are unobtanium, however.)


Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.