My 1966 Motor Manual doesn't list your axles, but the Rockweel name is in () and they are made by Timken..Maybe you can get the info from Timken..

Happy hunting..

Geoff
49 Chev 4400
59 Apache 32
52 GMC 350


Geoff


68 GMC 3800
56 JD420C w/JD90 Loader