I decided to remove the modern replacement rear shackles with zerk fittings on Betsy and go back to standard Ford shackles with oilers. I replaced the bushings in both the spring and perches and picked out the two "best" stock shackles from a bunch that I bought at Hershey last year. One side went in just fine, but the other side wouldn't go in.
No problem, the bushings probably just need to be reamed. Nope, a 1/2 inch drill bit slid right through without removing any metal. I went back to my stash and picked out a different shackle and it slid right in.
So, I measured the oddball shackle and both arms measure out at 0.560 - 0.565!
What do I have here, a TT shackle, or an oversize T shackle?
Shackles are approx. 9/16".
Ok, thanks Steve. Sounds like I found a pair of used shackles that are a good fit into un-reamed bushings.
I guess I need to get the proper reamer and a pair of new shackles.
So, I went to Lang's website to order the reamer and a pair of shackles, and I see in the description of the shackles:
"original design correct for show car".
I seem to vaguely recall that some of the reproduction factory-looking shackles are too soft and don't last long in regular usage, is that why these are described as "for show car"?
Looks like I have one original shackle that measures the full 9/16, does somebody have another original shackle that also measures the full 9/16 that they would be willing to part with?
Your car uses the standard U shape shackle. They are on ebay all the time. Get you mikes out, and when you install them, be sure to put them in the correct way. I see them all the time put in backwards! I was lucky when restoring my '25 about ten years ago, I was able to locate NOS script shackles. I prefer brass bushings for mine so as not to wear out the shackle, and I ream them with an adjustable reamer for a good fit.
I'll look on Ebay. I put the nuts facing the rear, like it showed in the Ford service manual.
I have the reamer on order from Lang's and will swap in the unworn shackles once I have them and the reamer in hand.
These types of reamers are handy.
A 14mm drill bit also works.
It is slightly smaller than 9/16".
Bob Bergstadt just came through with an NOS shackle to match the unworn one that I already have, thanks Bob!
A 14.5" drill bit or reamer will put the bushing hole back to standard size. .560-.565 is about right for an unworn shackle pin (not sure of the true exact size). I know the 14.5mm size equates to .570" .
Glad Bob was able to fix you up with a good shackle.
I must be one of those doing it wrong, I put the nuts on facing the front. Oh well.
If in doubt, I always refer back to the Ford service manual. It shows the nuts facing the rear of the car for both the front and rear shackles.
It's probably just dumb luck, but my worn shackles fit the un-reamed bushings pretty well, certainly well enough to make a few test drives before the unworn shackles show up.