I'd have to agree with Dan. Someone beat the snot out of the tube back around the rear dowel pin hole, too. Might be time to replace the differential and torque tube (you don't need to replace the whole rear axle, but you could. Might be an opportunity to install a 3.55 ratio ring and pinion at the same time.

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.