Topic: Differences between '65-'66 6cyl manual and 6cyl C4 Auto Driveshafts..?

[NEFaurora]

Subject: Differences between '65-'66 6cyl manual and 6cyl C4 Auto Driveshafts..?

Without me spending 2 hours going through books and Master Parts Manuals,

I thought that I would address this question here...

Does any know what the main differences are between the '65-'66 6cyl manual and 6cyl C4 Auto Driveshafts..?  Is it just the length of the driveshafts??  If so, What is the length difference?  Anyone know??   I have two to compare, but they are both installed in vehicles at the moment.. I'd have to put them both on a lift to check.  They should be 24 spline.

While we are still on the question, What are the differences between '65-'66 V8 manual and V8 C4 Auto Driveshafts as well ?

Much Thanks,

Tony K.

[C5ZZ]

Tony,
From what I have seen and found in the MPC 6 cyl AT and V8 AT use the
same driveshaft, 6 cyl MT uses smaller u joints and its a smaller diameter.
The yoke on the rear axle may be a different size as well.

[NEFaurora]

Really Good stuff...

 From what I have been able to find out, Most regular 6cyl 3spd driveshafts are identical to the 6cyl C4 Auto driveshafts (of the same year) thru the 1968 Model Year making a tranny swap really easy.  The same appears to hold true for the 8cyl 3spd driveshafts to 8cyl C4 Auto driveshafts. They are mostly the same, so you can re-use the same driveshaft thru '68.  I was not aware of this until today. I always thought that the 3spd and C4 Driveshafts of the same year were different and had to be swapped out when doing a 3spd to C4 and C4 to 3spd tranny conversion.  Not so.  Great stuff to know.  At worst, You might have to change U-joints because of some differences, and maybe a driveshaft yoke, but that's about it at most. The driveshafts are the same length.

Check out this chart below that someone directed me to..

http://mustangtek.com/differential/Driveshaft.htm

)

Tony K.

[J_Speegle]

Really Good stuff...

 From what I have been able to find out, Most regular 6cyl 3spd driveshafts are identical to the 6cyl C4 Auto driveshafts (of the same year) thru the 1968 .............

Tony, the statement does not seem to reflect what the chart you posted indicates. They appear that they will work but not the same. Example 66 200 6 cyl 3 speed 2 1/2 x 49 63/64  compared to 66 200 6 cylinder C4 2 3/4 50 25/32. These differences are likely the reason Ford had them marked differently

Same difference mentioned in all 65-68 applications shown. Also the site seems to be missing some application, likely just an oversight

Lots of parts will work in a swap - wrecking yards use to have a stack of 4" high books called exchange manuals to show them what they could sell to a customer from other applications

[NEFaurora]

Jeff, I can't attest to the accuracy of that chart, but what I can say is that I have spoken to quite a few people that have done tranny swaps using their same driveshaft in the swap, and just swapping out for a different tranny of the same year, just being opposite of what they originally had and the swap has worked out fine. Of course this is for just regular run of the mill 6cyl and v8 cars, not high performance models.  If you are referring to those old "Hollander" Interchange manuals.. I have a stack 1 foot high of them in my garage cabinet...lol..

PS: I also noticed on my 6cyl 3spd manual '65 convertible that the driveshaft Yoke is extended out about an extra 2 inches, meaning that my car could indeed accept a longer driveshaft.  On some of these cars, I think that an extra 1 inch or more on the driveshaft would not make a difference in most swaps and would still workout just fine.  It's not as critical at the front yoke as far as length is concerned. There seems to be a good margin for error for things to still work out.

)

Tony K.