The parts supply houses list 4th main bearings in .003, 005, and .010 oversize. My question-- what is the diameter of a standard tail shaft ?

Thanks

Mac's catalog,page180 lists ID for output shaft as 1.566-1.567 inches.

Thanks, Jack, that's what I needed. I could not figure way to know what oversize bearing one needs to order if I did not know the diameter of the original tail shaft. I knew the tail shaft must be larger than 1.50 but had no idea of how much larger.

Current 4th main from engine with broken crankshaft had .020 runout--- you think that might have helped trash the crankshaft ??

I'd bet it also trashed the center main.

If you have the trans apart, it wouldn't be a bad idea to check that the driving plate and output shaft run true. Polish the output shaft where the babbitt runs to near mirror finish too. A rough shaft will eat that thin babbitt in short order.

The output shaft is quite smooth, and the 4th main fits pretty tight. Since I have gone to the trouble of driving 535 miles to have the oil pan straightened on a KR Wilson machine, I thought it best to check the 4th main to make sure it was rebabbitted and bored concentric to the area that contacts the oil pan and hogs head. With the 4th main chucked and trued in lathe, indexed to the area that contact oil pan, then dial indicating the babbitt bearing, it was .020 out. With that wobble, I would guess that the person that bored the bearing chucked the snout around the bearing to hold the bearing being bored--- which resulted in a bearing that does not align with the oil pan and hogs head. That surely helped assure me of a broken crankshaft, and damaged block. Don't want that to happen again.

Doy,did you check run out on the tailshaft flange? I have seen them off a bunch! All that flexing has some strange side effects.