6.9 conversion
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6.9 conversion
i am trying to put a 6.9 disel into a 78 f-250 4x4. the truck has a c4 trans and the engine came with a c6 trans 2wd. c4 does not bolt up to the engine. Need advice to do this the cheapest way possible. thanks
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Joined: Mar 2007
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Just a guess on my part, but I thought Ford only put C-6s in the 4X4s, at least that was true with the FE powered F250s. What I do know is the C-6 that came with your diesel engine will probably be too long and have the wrong splines to mate up to the transfer case on your project truck. The cure, I think, would be a tranny rebuild with the proper output shaft(proper length), and probably a new input gear to match for the T case. Almost everything else will have to be fabricated, or stolen from a donor truck -probably both. Man, it's been years since I've done anything like that.
'73 thru '79 F250s were my favorite. Good luck
'73 thru '79 F250s were my favorite. Good luck
Lead Driver
Joined: Nov 2003
Posts: 6,900
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From: Campbell River, B.C.
Go with the C6, and if the transfer case doesn't fit, would just get another one that does, there are more fseries truck parts out there than you can shake a stick at.
C6 was the only auto ever offerd behind a 6.9, 2wd or 4wd.
C6 was the only auto ever offerd behind a 6.9, 2wd or 4wd.
i ain't rite
Joined: Mar 2005
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From: Marlboro Mental Hospital.
or you can leave the trans as a 2 wheel drive assembly, and put a divorced transfer case in it.
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Joined: Dec 2006
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From: Byron New York
Also a point of interest the stock 78 frame is 3.5 inches narrower than the frame the diesel came from. The transfer case is pretty tight in the wider frames 80-97. My brother in-law and I are working on a 71 and we found it was going to be easier to mount the cab and everything else to the newer style frame.