That part was cast in 1966. On the foundry stamps alpha digit denotes decade (ie. C = 60 D = 70 and so on), the next numerical digit is the year. The 3rd digit denotes intended vehicle, 4th is engineering division.
When I took the pic I was just looking for numbers on the flexplate then I noticed the weight was removed so they must have had a 0 balance. So the flexplate is no good to me. The trans I was looking for the numbers on the RH side but they are on the LH side. It’s from a 1972 Torino. When I decided to go to the dark side (Ford), I never realized what a crapshow everything is. My plan was to find a nice complete running S197 or possibly S550. When I saw this fox body I knew I had to have it, just wish I could have gotten it complete instead of a roller. Still waiting for my engine to be completed. Getting kinda discouraged but when it’s on the track it will be worth the hassle. 😊
the A servo was used from 1966 through 1983 as I remember and was probably the most common servo
the servos are marked with a letter which designates it's "size", which in turn dictates how the trans was originally built. R servo's were "usually" in cleveland powered cars. R servo shifts a lot better than A, and it holds the int band tighter-reducing slippage. There is A, C, H, R, O, Z, N, B and I know I'm leaving out at least one more. Those are just OTOH. They are all different and all have different original applications.
Then there were a bunch of C5's out there too, basically same as a C4 with differnet case-which is a little better from a performance standpoint. Use of C4 guts in a C5 case is kind of a normal deal. C4 and C5 are very similar externally and a non-ford person can't tell the difference.
there is normally a tag on the servo cover that has all the information, similar to a T5's tag
oftentimes, during a rebuild, the tag is tossed in the trash to never be seen again.
so without the tag nobody knows what you have, assuming that it is the original tag, until you take it all apart which I do on all of them anyway. They're decades old and have been apart how many times in that time period? And what was done inside when they were apart?
C4's are not all created equal, there were a ton of variants. Case fill, pan fill....completely different cases between the two, and each takes it's own style of bellhousing, of which there were different "sizes" depending on the application. 157t and 164t, and then there were some 4 cyl, again different. Then some had 5 clutch forward drums, some were 4.
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