I have built many Model T rear axles and Ruxtells over the years, but I ran into something this evening that I have never experienced before. (On my own car, of course!) Its a 1911 runabout, and it had a later through bolt style differential casting in it, which was worn where the thrust washers go. So, I picked a decent replacement out of the pile, but its a later stud type, with no thru bolts. After getting everything cleaned and ready to re-assemble, the differential casting would not bolt together tightly with the axles and spider gears in place. On closer examination, the shaft size on the differential spider gear trunnion, where it fits into the casting is .610" However, the hole in the casting is only 9/16" (.562") Not being at the shop where the pile is, I only had one other trunnion here with bronze bushings in the spider gears and center bore, but the shaft size on it is .510", and it is straight, not stepped for strength. WTF?? Did Ford make 3 or more different sized spider gear trunnions over the years? Are the later ones smaller than the teens and 20's ones, but the earliest ones smaller than the late ones? I have never seen this before. Thanx, Jeff
According to Bruce's C-D Parts Book info
2526 9/16" arm 1909-11
2526-1/2 5/8" arm with bronze bushing 1911-14
2526-B 5/8" arm, no bushing 1914-1927
So, my differential casting with 9/16" bores has threaded in studs rather than trough bolts. I was always under the mis-conception that the threaded studs were 26-27, not earlier.