slip yoke problem / TF 727

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360duster

360duster

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Hi Guys,

i bought a new slip yoke for my TF 727 trans. I´m not able to push this yoke into the trans, only light tapping with a hammer forces it in....to remove it also a hammer must be used. I did not push it in the whole way to avoid internal damage....what can cause this? I expect no problem with the trans, the car it came out shifted and drove properly.

Can anybody supply the correct outside diameter of a original mopar slip yoke to compare with this one?

Thanks for Info!

Michael
 
My first thought was......what happened to the old slip yoke? Chances are if you have to hammer the slip yoke in, it has a bad bushing, the output shaft is bent, or there is rust on the splines.
 
You have a newer slip yoke which has a different spline angle. There are involute and convolute splines styles and the newer slips won't work with the older trans

You need a older version, what was the part # you have for the slip yoke
 
Supershafts said:
You have a newer slip yoke which has a different spline angle. There are involute and convolute splines styles and the newer slips won't work with the older trans

You need a older version, what was the part # you have for the slip yoke
Click to expand...


You are right on the money with that . I ran into the same problem
 
hmmm, i bought this one from denny´s driveshaft, should be the correct one?

1 x [20729055] Slip Yoke 7290 Series 727 auto & A833 manual with 29/30 spline output

The trans is from a 1973 coronet station, does this matter?

Maybe i write an email to the vendor to see what they say. Bad that i´m overseas, no chance to ship this part back if it´s wrong...

thanks for the info!

Michael
 
Supershafts said:
You have a newer slip yoke which has a different spline angle. There are involute and convolute splines styles and the newer slips won't work with the older trans

You need a older version, what was the part # you have for the slip yoke
Click to expand...
what do you mean by different spline angle? can you show a pic or a link that shows that? and what is the cutoff year for those? i have a 67 727 that was missing a yoke and i pulled one out of a 84 dodge van that slipped right in.
 
73AbodEE said:
what do you mean by different spline angle? can you show a pic or a link that shows that? and what is the cutoff year for those? i have a 67 727 that was missing a yoke and i pulled one out of a 84 dodge van that slipped right in.
Click to expand...

I don't have a picture but what he's referring too is the angle the splines are cut at. It's hardly even visible to the naked eye but it is different. I'm not positive but I think it started with the advent of the A518 overdrive trans. which was 1990 I believe.
 
360duster said:
hmmm, i bought this one from denny´s driveshaft, should be the correct one?

1 x [20729055] Slip Yoke 7290 Series 727 auto & A833 manual with 29/30 spline output

The trans is from a 1973 coronet station, does this matter?

Maybe i write an email to the vendor to see what they say. Bad that i´m overseas, no chance to ship this part back if it´s wrong...

thanks for the info!

Michael
Click to expand...

Michael, by it's description on Denny's website it looks correct but if it doesn't fit apparently they are like the ones Mopar perf. was selling that was really for a A518 output spline.
 
73AbodEE said:
what do you mean by different spline angle? can you show a pic or a link that shows that? and what is the cutoff year for those? i have a 67 727 that was missing a yoke and i pulled one out of a 84 dodge van that slipped right in.
Click to expand...

2 different types of splines, you have to have them in front of you, one is sharper and the other is lets call it dull, the 727 is sharp, the 500/518 and the 42rh46rh/re all went to the convo style and what happens is the splines in the slip for the con spline interfere with the straight inv of the 727 spline making it a TIGHT fit, which if this was a end yoke....not a problem...

The change in the spline cut was around 90 or 92

dennys changes part numbers so no one can help you other then them
 
Put up a pic so i can see it from the side and then a pic of the spline area then i'll know if you got the wrong slip
 
Supershafts said:
2 different types of splines, you have to have them in front of you, one is sharper and the other is lets call it dull, the 727 is sharp, the 500/518 and the 42rh46rh/re all went to the convo style and what happens is the splines in the slip for the con spline interfere with the straight inv of the 727 spline making it a TIGHT fit, which if this was a end yoke....not a problem...

The change in the spline cut was around 90 or 92

dennys changes part numbers so no one can help you other then them
Click to expand...
ok thank you for the clarification
 
fishy68 said:
I don't have a picture but what he's referring too is the angle the splines are cut at. It's hardly even visible to the naked eye but it is different. I'm not positive but I think it started with the advent of the A518 overdrive trans. which was 1990 I believe.
Click to expand...
thanks fishy. i was unaware that the 727 splines were changed in newer vehicles.thats really good to know.
 
Supershafts said:
Put up a pic so i can see it from the side and then a pic of the spline area then i'll know if you got the wrong slip
Click to expand...

here are some pics, are they good enough?

Thanks Michael
 

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360duster said:
here are some pics, are they good enough?

Thanks Michael
Click to expand...

looks like the counterboring wasn't cleaned up otherwise its the right style spline. Some of the splines look wide and that is probably from the counterbore


fishy68 said:
I didn't say 727 splines changed. The slip yoke spline changed when the overdrive A518 came out. All 727 output splines are the same.
Click to expand...

The 727 when it went to the 518 and 46rh/re and newer style then it changed, same diameter and spline count, different cut of the spline.
 
Supershafts said:
The 727 when it went to the 518 and 46rh/re and newer style then it changed, same diameter and spline count, different cut of the spline.
Click to expand...

Yeah I'm familiar with the change. I said all 727 output shaft splines are the same because the 518 isn't really a 727. It's built off the 727 platform but a lot of things are changed/modified to the point where very few parts interchange.
 
Supershafts said:
looks like the counterboring wasn't cleaned up otherwise its the right style spline. Some of the splines look wide and that is probably from the counterbore
Click to expand...

The Vendor says also that´s the correct style, they expect a problem with the tailshaft bushing. But they say also the 727 and 518 spline is absolutely the same.............

I did not change the tailshaft bushing, in the donor car there was no problem with the driveshaft etc. Today i get another 727 slip yoke from a friend, will compare these two, maybe i can see a difference.

Michael
 
the hub diameter checked out ok. I got the other yoke to compare, this one slipped right into the trans as it should. And, as you can see in the pics, it has got some more coarse looking splines (first one is the one that fits).

So it really seems that the guys at DDS sent me the wrong part for a A518 Trans (they say it´s the same for 518 and 727....).

Unfortunately the one that fits looks like crap compared to the wrong one (the one from Denny´s is a nicely forged piece, very strong - the other one from Inland Empire Driveshaft is very rough, with burrs everywhere, and most of the meat is cut away on a lathe - i´d like the other one better if it would fit :violent1:

I´ll send these pics to the vendor to see what they can do for me.....

Lesson learned: A518 output shaft is different to A727.

Thanks for your support!

Michael
 

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Michael I don't know if it is a lighting issue with the one in the 2nd pic but it looks like the top part of the splines are more "pointy" and the lower section is a "duller" cut. Does it look that way in person or are they all "pointy"?

I looked at a 727 yoke I have in the garage and it has the "duller" looking splines like the one in your top picture.
 
I am having the same problem too, but kind of in reverse. I have a cast iron OD 833 out of a '75 Dart, and the yoke Brewer's sent me fits the same way 360duster described. But the funny thing is it fits my '68 A-body 833 beautiful with no problems. Both are 30 spline. I have to assume the early main shaft has a different spline angle than my later OD unit. I have the OD box completely torn down on my bench, and the yoke splines on the main shaft are perfect. No burs or dirt. WTF!!!
 
fishy68 said:
Michael I don't know if it is a lighting issue with the one in the 2nd pic but it looks like the top part of the splines are more "pointy" and the lower section is a "duller" cut. Does it look that way in person or are they all "pointy"?

I looked at a 727 yoke I have in the garage and it has the "duller" looking splines like the one in your top picture.
Click to expand...

Yes, that´s the way it is, no lighting issue. The splines are more narrow in the top at the wrong one.

We´ll see what the vendor says, otherwise maybe i´ll come back to you regarding the Yoke.....;-)

best regards

Michael
 
360duster said:
the hub diameter checked out ok. I got the other yoke to compare, this one slipped right into the trans as it should. And, as you can see in the pics, it has got some more coarse looking splines (first one is the one that fits).

So it really seems that the guys at DDS sent me the wrong part for a A518 Trans (they say it´s the same for 518 and 727....).

Unfortunately the one that fits looks like crap compared to the wrong one (the one from Denny´s is a nicely forged piece, very strong - the other one from Inland Empire Driveshaft is very rough, with burrs everywhere, and most of the meat is cut away on a lathe - i´d like the other one better if it would fit :violent1:

I´ll send these pics to the vendor to see what they can do for me.....

Lesson learned: A518 output shaft is different to A727.

Thanks for your support!

Michael
Click to expand...


Dennys isn't forged that's either a neapco 7290 slip with there own numbers or its a powertrain piece or it's from china, whats the casting number in the slip or the name or letters.
Where is a pic of the inland slip ?
Detroit is the only company that made those slips in there series they are now copied by others.

.
 
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