NP241C yoke leak ?

[440sixpack]

 My k10 has a 700r4 with a NP241c behind it.  both were fully rebuilt not long ago and have worked perfectly.   now sometimes I see drops of  ATF coming off the u joint on the  rear output.

 It absolutely isn't the seal, it's bone dry.  but I see there is a soft plug looking thing in the yoke.  is it possible the oi could be leaking from that?  I can't see it but I can't think of anyplace else it could be.  I'm not sure what's behind it.

[Irish_Alley]

generally if its the yoke it will fling trans fluid up on the bed. what style output shaft does the t-case have? i imagine its a slip yoke but idk. i know we've talked about it before on here about an o-ring on the output shaft, try using the search button. im going to look myself but i haven't found it yet

[440sixpack]

yes it's a slip yoke. and yes there is a little oil on the bottom of the cab.

I wondered if there was an o ring.  if there is that's probably it.

[440sixpack]

I pulled it out and it turns out there is no o ring.  but the leak is coming from oil seeping around the edge of the soft plug in the yoke. 

I covered it good in The Right Stuff and I expect that will be the end of it.  if not I'll do something more durable.

[Irish_Alley]

you can plug the hole but as the suspension moves the slip yoke will travel in and out of the trans and will blow the sealant out. heres a write up on the weep hole, i know theres a few that have had this issue but pretty sure theyre 4x2 not 4x4. i dont know if its the same setup or not.
http://73-87.com/7387garage/drivetrain/yokeleak.htm