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Dec 3, 2001 | 03:34 PM

Craig

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From: Campbell U S A

trans change...

I may have asked this before, but I don't remember getting an answer.
Will the C6 transmission I want to put into my '56 fit up the flexplate on my 351C that is currently hooked up to an FMX transmission? And if not, what might be a good choice for a new flexplate? I assume the engine would have to come out for a flexplate change, but I'm not sure as I've never had an automatic to play with before. Thanks folks!
Craig from Campbell

Dec 3, 2001 | 08:48 PM

mtflat

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From: Kalispell, MT

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Craig,
Unless you have one of the 'baby' C6's the flexplate is the least of your worries. The built-in bellhousing of the C6 only matches the pattern on the 351M, 400, 429, 460 engines.
Your 351C is the small pattern bell.
I'm not sure about the flexplate question - I'll watch for an answer with you.
Tim

Dec 3, 2001 | 09:10 PM

cobraguy

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From: San Diego CA

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Yes the flexplate will work on a C6 as long as it is the correct flexplate for the Cleveland. The hard part is finding the C6 with the smallblock bolt pattern. They are available but pricey. Your tranny options on cars with the Cleveland were FMX, C4, and C6. Most of the C6s would be found in Mustangs MachIs and such. Good luck, Rich

Dec 3, 2001 | 10:29 PM

Craig

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From: Campbell U S A

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Oh man the small block pattern! I knew I was forgetting something. Thank God it was cheap. I just came back from my garage. Looking at the junk yard yellow ink it came out of an '84 van with a 302. How's that sound?

Dec 4, 2001 | 01:48 AM

mtflat

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From: Kalispell, MT

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If the tranny came off a 302, then it will fit your 351C. Chances are good that it's a C4 instead of a C6.

Dec 4, 2001 | 09:28 AM

truckfarmer

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From: Illinois

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the trucks and vans used C6's. It should bolt up to your Cleveland. The flexplate will be the same. It will be longer than your FMX. An 84 van would be pretty close to when they started putting AOD's in them. You can tell an AOD because it has no vacuum line going to it.

Dec 5, 2001 | 09:46 PM

Craig

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From: Campbell U S A

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Thanks for the input guys.
The year is actually '81, I used the drop light to read it tonight. I found an old file I got from this site a while ago that shows the shape of the pans on various transmissions. The C6 picture fits exactly with what I have. I also got the numbers off the tag bolted to the case. It reads, "PGD BN11 E20 E1UP GB012831". Just for background information, does anyone have a clue as to what it all means?