C4 vs. C6

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Sep 3, 2009 | 11:48 PM

hot_bod_247

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C4 vs. C6

i hav a 78 F150 custom with a 302W and a 3 speed auto C4.
my question is is a C6 bolt patern and spline teeth identicle 2 a C4?

Sep 4, 2009 | 01:01 AM

85e150

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C6 for the 302 will have the same bell pattern, probably the same splines, but I think you need a torque converter for the C6.

You swapping trans due to a failure or other reason? The C4 is strong enough for your application. And the rebuild on a C4 is probably not a lot different price wise than the trans swap, esp. if you have to buy a TC....

Sep 4, 2009 | 06:04 AM

RTM

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Double check on the output shaft splines. I think the C4 is 28 splines and the C6 is 31 splines?

Sep 4, 2009 | 10:35 AM

hot_bod_247

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well im going 2 have 2 replace the drive shaft so i wont have 2 worry about the output shaft yet. and the problem with my C4 is that i've lost drive and reverse and it was run so long without an oil or filter change that the oil looked worse than used engine oil. my other question is is which tranny is best for 4X4?

Sep 4, 2009 | 04:45 PM

85e150

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How long did the C4 run?

A C6 is stronger, but eats more power, and will require some adapting.

I would simply swap a reman'd C4 in there, maybe add a little beef to it.

Sep 4, 2009 | 04:54 PM

hot_bod_247

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well i'd rebuild the C4 myself if i knew what i was doing or if i even had the tools.
should i have this one rebuilt by a shop or should i find a different one in a junk yard?