SLIP YOKE QUESTION for 1970 C10

[1970DAVE10]

Changing out my u joints on my 1970 C10 drive shaft. In observing the slip yoke that slides on the end of the transmission, I noticed all the teeth were fine except for an entire row. The transmission teeth are all fine and don't appear to have any chips or issues, just usual wear.

Is this built this way? An entire tooth line (excuse my verbage) from front to back is missing on this thing. All the other teeth rows fine. I'm thinking it's supposed to be that way. Any help would be great. Started with doing the motor, this, that, and now I find this, it's like peeling an onion.

This is attached to a Saginaw 3 Speed. Thanks for the time in advance.

[vasquezmrysvll]

all that iv seen are the same, i maybe to ease slipping it on the output shaft?

[Tx Firefighter]

That's called a blind spline. It's normal. GM did not use it in this application, but the yoke maker broached it like that anyway.

The reason for it it to allow one way indexing on something onto a splined shaft. The shaft would have the matching spline so you could only install the yoke exactly indexed with it.

[brad_man_72]

alot of 2 piece shafts use a blnd spline so people that aren't complete idiots can take the shaft apart and put it back together without disrupting the ballance of the shafts...
in this case it's to let air excape when the suspension moves the shaft in and out of the trans.

[1970DAVE10]

Thank you guys for the info. Yeah, no expert here on slip yokes. Just trying to change out the u joints. Again, thanks for the time.

[brad_man_72]

back to changing ujoints. Did you mark how the pieces were before you took it apart so you can get it back in time with the way it was ballanced (assuming you're replacing the original ujoints). Even if you don't "feel" a vibration it can damage the trans yoke, tailshaft bushing, carrier bearing, and pinion bearing.
I you have any doubts take the shaft to a DRIVELINE shop to have it ballanced.

[centuryhouse]

Originally Posted by brad_man_72

back to changing ujoints. Did you mark how the pieces were before you took it apart so you can get it back in time with the way it was ballanced (assuming you're replacing the original ujoints). Even if you don't "feel" a vibration it can damage the trans yoke, tailshaft bushing, carrier bearing, and pinion bearing.
I you have any doubts take the shaft to a DRIVELINE shop to have it ballanced.

Could you explain this a little more?

[ETA: sorry, I didn't realize this was an old thread!! I forgot I had accessed it via Google, instead of when looking at current threads. My apologies.]