727 Output Shaft compatibility

jcslocum

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Hello transmission experts. I have a 1966 Fury 3 (318 Poly) wagon with a blowed up 727 trans. I can rebuild the current '66 727 but it has very limited options available for this year/model, particularly the torque converter. I plan an engine swap later this year so want to upgrade the trans now and use it for the summer.

I have picked up a 78 727 from a motor home with low miles BUT it has the E-Brake on the tail-shaft. The question, is will my current '66 727 output shaft work with the modern heavy duty 727? I recall reading somewhere that the inner end of the shaft won't match up to gear cluster inside the trans. Does anyone know for sure?? I can pickup a more modern tailshaft and use that but need definitive info on this issue.

Thanks for any help. I really appreciate it.
 
That's the way I understand it. The early and later than 74,75,76 not sure of year exactly spline shape changed. It will go together but is on the clock for possible failure. I would put the 78 front into your case. Better pump support, possible wide drum, and 4 pinion.
 
Thanks for the info.

So, use the new 727 stuff in the front half of the trans and retain the old stuff in the back half.

So you think I shouldn't worry about a new output shaft?
 
From the Poly, what engine upgrade you planning?? LA block? Or big block?
Frankenstiening the RV trans is not cost effective even if you got it for free it will be a headache.
Spending a dollar at the tranny shop just to save a nickle.
Best off getting a early 70's passenger car 727 core and rebuild it.
Even a Loadflite from a 70's D100 pickup or tradesman van will work.
Best of both worlds...fits right behind the Poly and broadens your convertor choices.
We rebuilt a 72 727 and put in a later input shaft. The car did not move..trans was a lump until we put back proper input shaft.
Hope this helps just my 2 cents
 
That's the way I understand it. The early and later than 74,75,76 not sure of year exactly spline shape changed. It will go together but is on the clock for possible failure. I would put the 78 front into your case. Better pump support, possible wide drum, and 4 pinion.
...And in the valve body the 3-2 part throttle kickdown feature not present in his 66 trans.
I butchered a truck 1973 727 and used parts from it into the BoaB's big block 1968 727.
But left the input and output shafts alone.
As you mentioned the RV innards includes the 4 pinion just like the Hemi 727.
Also today's modern technology and materials clutch band quality is much better.
 
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Use your 1966 casing but with RV guts.
Toss the RV rear casing half..
:thumbsup:
 
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I hope the OP realizes the A/LA and B/RB bell housings has different bolt patterns that do not interchange...
 
From the Poly, what engine upgrade you planning?? LA block? Or big block?
Actually, I'm going old school Hemi. I have a 354 on the stand with 10:1 pistons mild cam and a 4bbl.

...And in the valve body the 3-2 part throttle kickdown feature not present in his 66 trans.
As you mentioned the RV innards includes the 4 pinion just like the Hemi 727.
Also today's modern technology and materials clutch band quality is much better.

What if I transplant the RV trans with the new tailshaft. It's a 727 non-lockup trans.

Yep valve body also from 78.
Just take the pump and input, front drum Not the whole case and what not.

That is sort of the plan. I was worried about the output shaft not matching.

I hope the OP realizes the A/LA and B/RB bell housings has different bolt patterns that do not interchange...

Yes, I'm aware that the bolt patterns are different. The "new" RV trans is from a 440/727 combination.
 
Actually, I'm going old school Hemi. I have a 354 on the stand with 10:1 pistons mild cam and a 4bbl.



What if I transplant the RV trans with the new tailshaft. It's a 727 non-lockup trans.



That is sort of the plan. I was worried about the output shaft not matching.



Yes, I'm aware that the bolt patterns are different. The "new" RV trans is from a 440/727 combination.
So..you answered your own question and still not getting it
The 440/727 will not bolt up to the Poly--different bolt pattern.
Yer putting the cart in front of the donkey here..
A waste of time trying to change the tail stock,output shaft and find out it will not bolt to the Poly.
Best to take the good guts out of the RV and put them in your 66 727.
That is a trans I would buy when no longer needed.
As for the future Hemi,possibly an adaptor plate to match its bell housing or a different trans altogether.
Done repeating myself :BangHead:
 
I'm not sure what year the bellhousing is not part of the block and also the crank flange is different on some of those. I'm not too good with their intricacies, others here know better than I do.
 
I recall reading somewhere that the inner end of the shaft won't match up to gear cluster inside the trans. Does anyone know for sure??

The spline angle is different on the front of that output shaft, for sure!
 
The spline angle is different on the front of that output shaft, for sure!
This.

Look up the procedure to properly swap the later front pump into your 66 trans. It's a common upgrade. Use the later valve body with the part throttle kick down and finish with new bands and clutches.

4 pin planetaries are highly overrated. The aluminum splines in the hub are the weak link, not the pinions. A super stock racer friend of mine used to remove 2 pinions on a 4 pin set on their AA/SS Hemi and never ever broke a pinion. Stripped out the splines on a few figuring out how many laps they would take before failure.

Kevin
 
Thanks for your patience and info. I will now transplant the newer front bits into the old trans with new clutches and bands.
 
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