MTFCA Forum

I just picked up a "pair" of TT radius rods. I put pair in quotes because they're not exactly alike. While they're both the same length and appear to be a functional pair, one has a long constant taper, while the other tapers down from the rear, going forward, then has a more pronounced stepdown. Are AA radius rods similar to TT? Would this explain the inconsistent tapers between the two rods? Neither one appears to have been altered in any way.

Hi Jerry, Like the passenger car parts, TT parts were up-dated/changed during production. There were at least 4 major changes in the car radius rods, (some people say there were as many as 8 versions). The TT had at least 2 versions. The one with the "continuous taper", (early), and one that was "stepped", (late). I know of at least one other version, but I've only seen one rod of that type so I won't go into that right now. I'm not exactly sure when the rods were changed, but I suspect it was about the same time Ford started supplying factory cabs, (1923-24). The change to the stepped rods could have been as late as 1926-27. The Model AA radius rods have a completely different casting where they connect to the differential housing/backing plate. I hope this helps some. Regards, Bill

Thank you Bill, that's exactly the info I was hoping for!