differences in 727 transmissions

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Elwood blues

Elwood blues

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Can someone explain to me the difference in some of the 727 transmissions? like is one out of a truck the same as one out of a car? what kind of cars are good donors to find these in? and if i find one how will i know if it will fit in my car, like if it has the right tail housing and what not? looking for one to put in my 71 scamp behind a 5.7 hemi so i at least know it needs the small block bell housing.
 
Different things to look at.......

Some have mounting ears for console linkage (I did pull one from a 1/2 ton truck once)

From a 1 ton or motor home at least in some cases, no slip yoke, very short tail shaft with a U-joint yoke.
 
Another thing to check - Speedometer pinion & housing.

It changed at some point in or before 1976, totally different type.
 
Tailshaft housing measures 18 1/2". No bolt on yoke or cable operated. 71 or later for wider direct drum bushing and PTK part throttle kickdown valve body. 24 spline input shaft--not 19. The two top bolt holes are about 7 3/4" center to center on the small block case.
 
The small block bells are kinda flat on the pass side while the big blocks are pretty much round, the big blocks have 4 little 1/4 20 threaded holes for the dust cover. The later model the better usually, Chrysler improved and strengthened the 727 as the years went by.... for the most part. Stubby shaft truck units have many good parts- you just need to change the output shaft and extension housing. I would rather start with one from a 78 pick up truck than one from a 69 road runner. Most 1/2 ton 2wd truck trans will go right in a car with no mods.
 
So is it better to pick up a truck one then? because thats easier for me to get and sounds like that will work better and fit right in.
 
jas0162 said:
The small block bells are kinda flat on the pass side while the big blocks are pretty much round, the big blocks have 4 little 1/4 20 threaded holes for the dust cover. The later model the better usually, Chrysler improved and strengthened the 727 as the years went by.... for the most part. Stubby shaft truck units have many good parts- you just need to change the output shaft and extension housing. I would rather start with one from a 78 pick up truck than one from a 69 road runner. Most 1/2 ton 2wd truck trans will go right in a car with no mods.
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So it is just 4wd trucks that you would have to change the output shaft and the extension housing or would you need to do that with the 2wd truck transmission too?
 
The truck 2 wheel drive has the cover for the tailshaft bearing clip on the side instead of under the rear mount.
Nice for removing the tail housing easier and faster.

!!!BUY THIS BOOK!!! ??
 
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Elwood blues said:
So it is just 4wd trucks that you would have to change the output shaft and the extension housing or would you need to do that with the 2wd truck transmission too?
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No not just the 4x4s.
The motor home and big trucks and some vans used shorty tailhousings.
They have the strong guts, very good stuff.
Just use the long output shaft and housing and follow Tom Hands book.
 
IMO the best ones to get are the 71-73 model that came behind a 340 but their not always easy to find. They have the wide front stator bushing, part throttle kickdown, 4 pinion planetary gearsets, and 4 clutch discs in each carrier. Many of the newer units used 3 pinion planetaries and less clutch discs in the carriers. HD truck or motor home trans are also good ones because they usually have 4 planetaries and 4 disc clutch carriers but some have a bolt on yoke instead of slip yoke and if you have a factory floor shift most truck extension housings don't have the necessary bolt tabs to bolt the linkage to but you can easily remedy that with a extension housing change

You also have to keep in mind that if your trying to piece together a strong 727 that the spline angle changed in 76 so you have to use the correct year span front planetary set on the output shaft that your using.
 
So I found a 727 from a 79 lebaron with a small block housing would that work with the set up I'm trying to do?
 
Hmm a 727 in a LeBaron.. 79 was the first year for the lockup so you might want to check the front tip of the input shaft if it has a smooth section for about 5/8"; the splines don't go all the way to the front.
 
Elwood blues said:
So I found a 727 from a 79 lebaron with a small block housing would that work with the set up I'm trying to do?
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Personally I would pass on a 79. The reason being I remember in 79 at the dealership across the road from our shop used to pull those Transmissions out and plug the lock up on them because they were having so much trouble with them.
 
Elwood blues said:
Is it better to look for one with out the lock up on it? Why are they not wanted/bad?
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Those were the first generation lock up Transmissions that Chrysler built and they had their problems.

The 500 and the 518 which are now the RH 42 s or r h 46 are a different set up, much more dependable.
 
I also found one from a 68 new port but it has a big block bell housing so i would need to switch it with a small block one, would that be a better choice?
 
Elwood blues said:
I also found one from a 68 new port but it has a big block bell housing so i would need to switch it with a small block one, would that be a better choice?
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You posted earlier that it was easier for you to find a truck transmission than a car. What trucks do you have a transmission available from.?
 
Theres a junk yard I frequent that has a lot of older dodge trucks however when I went to check if the had transmissions today they were all picked. The only ones I found were in cars.
 
Elwood blues said:
Theres a junk yard I frequent that has a lot of older dodge trucks however when I went to check if the had transmissions today they were all picked. The only ones I found were in cars.
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Ok get a 70-77 small block tranny from behind a 360 if you can
 
so right now i can either pull the one out of the 68 new port with the big block housing or i found one is a 74 dodge van but i'm not sure if it would have the long or short tail shaft on it. I think i need the long tail shaft to make it work? but im not sure could someone verify that.
 
Elwood blues said:
so right now i can either pull the one out of the 68 new port with the big block housing or i found one is a 74 dodge van but i'm not sure if it would have the long or short tail shaft on it. I think i need the long tail shaft to make it work? but im not sure could someone verify that.
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Can you get a picture of the van transmission tail housing.
If it has the short tail housing you can use the one from the big block if it has the long tail housing. Need a picture of it too.
Nevermind on the big block transmission picture , it's coming out of a car so it's a long tail shaft.
 
  • Forget the 68 bb trans. It has the narrow direct drum bushing and the old style valve body without ptk (part throttle kickdown). A 72 to 78 sb trans will have everything you need.
 
So i talked to the guy with the 74 van trans and he says it has the long tail housing so it should work for the car now i just have to wait for him to pull it so i can go pick it up. thanks to everyone for helping me with this learning experience, now onto picking out a good rebuild kit for it.
 
Elwood blues said:
So i talked to the guy with the 74 van trans and he says it has the long tail housing so it should work for the car now i just have to wait for him to pull it so i can go pick it up. thanks to everyone for helping me with this learning experience, now onto picking out a good rebuild kit for it.
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I don't know of any bad kits. None l know of have selective thrust washers so no kit l've seen is "complete" anyway. But check the endplay before you pop out the pump, and take out the front drums before you order parts. If you need another trans for some guts, it might have some good clutches and bands, unless you're going red eagle and kevlar.
 
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