One could spend a fair amount of time with a thread file & get a nut to go on but it looks like it has had a "Okie knurl" job on the outer bearing surface of the axle as a "repair " after the bearing spun earlier in it's life.
BC 1960 Chevy C10 driver 261 T5 4.10 dana 44 power loc 1949 GMC 250 project in waiting 1960 C60 pasture art Retired GM dealer tech. 1980 - 2022
