[Found!] Slip Yoke

-
Status
Not open for further replies.
carfreak6970

carfreak6970

Well-Known Member
Joined
Jul 25, 2014
Messages
545
Reaction score
195
Location
Pittsburgh
Rating - 100%
1   0   0
Contact seller
Hello Folks,

So I am in a pickle, yet again!!! I got a drive shaft made for my 67 Dart GTS and according to Brewers website, a 67 big block A body should have a 30 spline output shaft. So I got the drive shaft made with that slip yoke and a 30 spline slip yoke. Well go to install it and it wont fit!! It appears that the car has a 26 output spline shaft...

So I have a couple methods to cure this problem:

Get a Slip yoke for a 26 output shaft, and a 7290 U Joint.

Get a conversion U joint from a 7260 to a 7290 end.

Or remove the transmission, disassemble it and put in a 30 spline output shaft....


I would really not like to tear down the transmission, and I prefer not to use a conversion U joint. So that leaves me with trying to find a slip yoke for a 26 spline output shaft and a 7290 U joint.

So would anyone have that style slip yoke? Ebay and summit dont have anything listed.

thank you
 
Here is another source, I have the 1350 quick change one..

1350 Pinion Yoke - Driveshaft Yoke, Pinion Yoke, Forged Yokes, U Bolt - Inland Empire Driveline Service
transmission.jpg
 
Maybe they make an aftermarket one? I don't recall ever seeing a big U-joint on a factory 26 spline yoke. What kind of horsepower are going to put through it?
 
Locomotion said:
727 is 30 spline and 904 is 26 spline. But I heard there may be a difference with later model OD versions, but not sure of the details.

Denny's Driveshaft Slip yoke for Dodge Mopar 727 904 automatic and A833 manual transmission 26 and 30 spline output
Click to expand...

Thank you for that. That is the one source I was looking at. At one point they had this:
Slip yoke 7290 series fits Mopar Dodge 904 automatic transmission with 26 spline output

Which leads me to believe they indeed did have the 26 spline with the 7290 U joint. I was under the impression the transmission in the car was original too it, but I have no way of know. I dont know if the trans was taken apart and the tail shaft was replaced. So this car could have always been a 26 spline with the small u joint.

Heywodja said:
Here is another source, I have the 1350 quick change one..

1350 Pinion Yoke - Driveshaft Yoke, Pinion Yoke, Forged Yokes, U Bolt - Inland Empire Driveline Service
View attachment 1715685490
Click to expand...

Thanks for that. That would still require me to use a conversion U joint. If I am going to use one of them, Ill use the 26 spline yoke I already have and go from a 7260 to a 7290

cudamark said:
Maybe they make an aftermarket one? I don't recall ever seeing a big U-joint on a factory 26 spline yoke. What kind of horsepower are going to put through it?
Click to expand...

I havent had much luck finding an aftermarket one. Id be shocked if I am pushing over 400 with this car. Just a 383, with the typical 906 heads, factory iron intake and a slightly hotter cam.
 
Thanks for that. That would still require me to use a conversion U joint. If I am going to use one of them, Ill use the 26 spline yoke I already have and go from a 7260 to a 7290

Give them a call
 
I would use the 26 spline yoke you have along with the conversion U-joint and not worry about it unless you can find the unicorn one.
 
I think I have one of those conversion joints.. if you want it pm me
 
There is a OE application for a 7290 904 yoke. I can't remember what I got this one out of but the number on it is 52097955. Here it is in a /6 904 with a 7260 posing above it.

9047290.JPG
 
FWIW, I can't see a 26 spline slip yoke fitting because that's a 904 spec. Since you have a 383 big block, they only accept a 727. I doubt very much that anyone would switch shafts and I doubt it's even possible. The tailshaft bushing has to match too and they are a different diameter.
 
Hopefully your transmission is not a mix of mismatched parts like a 26 spline mainshaft with a tailshaft housing for a 30 spline yoke but that would be pretty obvious. Here is a '67 273 26 spline A833
A833904.JPG
 
I assumed that his transmission is the '66-7 25/6 spline version of the 833 4 speed. Correct us if we're wrong.
 
I believe my transmission is the 25/26 spline version of the A833. Because the only slip yoke that slides in the back of that transmission is a 25/26 spline slip yoke...

The restoration link is in my signature. However I do not have a good picture of the casting numbers for the tail shaft on there. So I may have to look on my personal computer.

so this car is either an odd ball that left the factory with the 26 spline output shaft, or the trans was swapped out (probably due to abuse) at one point.
 
Yes, factory installed is possible since all '67 A-bodies used the small 7260 u-joint regardless of output splines, engine, etc. It just so happens that the only parts catalog that I have is a '67 which shows this. Hardly relevant here at this point but more of an FYI since you already have a 7290 driveshaft. In the picture ,the 2660669 yoke for '67 383 A-bodies is a 30 spline 7260 yoke. Too bad there is no partial vin on '67 transmissions.
67833.JPG
 
I run 7260 on my two 71 Demon Stock eliminator
race car for last 30 years
that run mid 10s with 1.33 60Ft without an
issue as long as pinion angle is 2 to 4 down!
 
There are different lengths as well . Make sure you get one with adequate spline engagement or you could have a high speed vibration.
 
That has to do with the driveshaft length, not the yoke. The yokes are all very close in the centerline to spline distance. Whether the yoke has 7 inches of splines or 14 inches of splines makes no difference in regard to balance or vibration. It just needs to be inserted into the extension housing the proper distance.
 
Well seeing how I just went thru this and verified the engagement with the tailshaft off I can tell you it does make a difference. No more vibration .....
 
So that slip yoke was determined not to work with my application. So still on the prowl, but it is looking more and more like the conversion U-joint will be my best bet.
 
Status
Not open for further replies.
-

Back
Top