Have a 1969 Mustang 428 CJ, C6 PGB-Af1 automatic transmission. The case is damaged and needs replacing. Unable to find the correct transmission or a case. What other C6 transmission is compatible? Engine, Felxplate, starter and shifter linkage
The case is a case . I really don’t think welded case is junk .sand work down the weld glass bead it , call it done for me
You have a proper C6 CJ trans with the cast iron tail housing. You should be able to use any FE C6 case with all of your guts transfered over. There could be some small casting differences but should be OK. Biggest loss would be your vin number right there on top of the case in front of the tail housing.
Shouldn’t be too hard to find a core C6. Be sure to keep the r-code servo, the governor, cast iron tail shaft housing. Looks like a pretty good repair, whoever did it.
Have you considered using a newer transmission from Ford or GM? You'd need a controller, but the advantage of having more gears and OD might be worth the cost.
What is the end goal here? I ask because that will determine what your options are. If your goal is to keep all the numbers matching: Your best bet is to get on some of the FE and Mustang forums and find a similar date coded C6 case or transmission that can be swapped out. This will be the hardest to find. If you goal is to replace the case and not worry about the numbers, any C6 with an FE bellhousing will work. As others have said, transfer the guts and bolt on bits to the replacement case and move one. The down side is Ford hasn't built an FE engine for nearly 50 years and good FE C6 transmissions are getting harder to find. Mid 70's pickups are your best option. If your goal is to get it back on the road, with any functioning automatic tranny, then you could also look for an older Cruis-O-Matic or FMX built with the FE bellhousing. These transmissions were typically found in full size cars of the era (Galaxies, Lincolns, etc.) Any more modern transmission will require an adaptor (Add $1000) to mount to the FE engine. An adaptor does open up the possibility of using AOD's, Small and Big Block C6's, E4OD's, E6OD's, and even some Chebbie stuff, but comes with additional costs.
Is it the correct flexplate? 428 flexplate has an external counterweight, 390 does not. Correct starter for the application? Are the block dowels in place? Is the engine to trans midplate installed? Do you know what caused the original damage to the trans bellhousing?
You have the reinforcement ring installed right? If not it will crack the flex plate around the bolt holes.
Correct Flex plate with external counterweight Correct Starter Pin in place Midplate Yes I don't know, however, if I lay a straight edge across the bellhousing in the repaired area, there is a 1/8 difference
I would find something more rigid and dead flat and then check for straightness. Those mid-plates tend to warp a bit, at least the couple spares I have for 429-460’s.
The problem I have with that repair is the dowel pin. Was the piece welded back in the right place, not pulling the trans off center. As for the gap, it's wrong and probably pulled when welded. Should of kept it bolted to a block for welding. Anyway I would try building up that gap with some aluminum expoy, carefully sand it back down to a flat surface, that is if you feel the dowel pin is in the right place.
We never did find out what case casting number it is. That's the starting point for finding a replacement.
FWIW, F series til '76 used 360/390 FE engines and C6. So there should be, at least, a decade worth of FE C6 cases available Date/casting codes on the other hand...
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