Author Topic: NP241C yoke leak ?  (Read 130 times)

Offline 440sixpack

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NP241C yoke leak ?
« on: July 10, 2019, 11:35:09 PM »
 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.

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Re: NP241C yoke leak ?
« Reply #1 on: July 11, 2019, 01:13:02 PM »
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
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Offline 440sixpack

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Re: NP241C yoke leak ?
« Reply #2 on: July 11, 2019, 04:29:47 PM »
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.

Offline 440sixpack

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Re: NP241C yoke leak ?
« Reply #3 on: July 11, 2019, 10:29:46 PM »
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.

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Re: NP241C yoke leak ?
« Reply #4 on: July 12, 2019, 09:57:28 AM »
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
If you canít tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes