Fluid leak from transfer case rear center of yoke?

[whiteeagle]

I just purchased an 83 Eagle wagon with 42k miles and it has the NP 129 transfer case that is leaking fluid from the center of the rear yoke? I removed the drive shaft from the yoke and cleaned all areas around yoke and seal to reconfirm that the leak is in fact coming from the center and not from the outer seal? I cleaned and blow air around the vent on top of the transfer case, checked fluid level to ensure that it was not over filled reassembled the drive shaft and still today I have this slow leak from the center of the yoke. Any advice would be appreciated. Thanks. See attached image.

[eaglefreek]

Was there a rubber washer or seal behind the nut? I believe there is supposed to be one there to keep the fluid from coming out of the splines.
http://www.jeep4x4center.com/washer-front-yoke-rubber-4210973.html?utm_source=google&utm_medium=productfeed&utm_campaign=cse&gclid=Cj0KEQiAu_GmBRDhtK-kzqKcuJwBEiQAJvB8nzqhIj-tKBl9LxxNQKdYgB1taI2ZLVBpvVPdG5NJ4NgaAmtm8P8HAQ

[whiteeagle]

Thank you for your response partner.
 I just was reading the same link you provided.
 I thought it was a metal washer behind that nut and didn't realize it was actually a rubber seal. I have yet to remove the nut to examine but it would make sense to me that this would be the problem. I'm waiting for father in-law to get home so I can borrow his jumbo impact socket set and driver
Cheers

[carnuck]

Sometimes the yoke can crack too. I make sure it's not cracked or sloppy (if the nut comes loose, the splines get worn down) then put black silicone sealer or even better, atf proof silicone sealer on the splines and put the yoke back in and tighten it up.

[whiteeagle]

Job completed. It was the rubber washer behind the nut. I also used the atf proof silicone sealer as recommended.

I had a heck of a time figuring out what size socket fits the yoke nut. For the record its a (33mm metric socket) and after many calls and trips to auto stores I finally found one at Maryland's largest Pep Boys store in Glen Burnie. 

While I had the drive shaft off I replaced both the front and back u-joints as well. The parts catalogs say the front and back U-joins were the same but not true the back has the inner and out clips vs the front only uses outer clips. CARQUEST had the Spicer U-joints I needed.

Next project...replacing leaking plastic valve cover...

Thanks for all the feedback guys.
Cheers.

[eaglefreek]

I had a heck of a time figuring out what size socket fits the yoke nut. For the record its a (33mm metric socket) and after many calls and trips to auto stores I finally found one at Maryland's largest Pep Boys store in Glen Burnie. 

.

1-1/8" works also, if I recall.

[carnuck]

Some are 1 and 3/16"

[djm3452004]

Hi all --

Not trying to resurrect an old thread, but can anyone confirm the spline seal P/N listed at the Morris 4x4 site is the correct spline seal for the NP129 transfer case output shaft(s)?

Crown Yoke Washer Seal, P/N 4210973

https://www.morris4x4center.com/washer-front-yoke-rubber-4210973.html?utm_source=google&utm_medium=productfeed&utm_campaign=cse&gclid=Cj0KEQiAu_GmBRDhtK-kzqKcuJwBEiQAJvB8nzqhIj-tKBl9LxxNQKdYgB1taI2ZLVBpvVPdG5NJ4NgaAmtm8P8HAQ


Is this the only place to get this?  I've checked all the usual parts houses and this P/N does not seem to cross to anything, nor do they list any such spline seal as required.  I don't mind ordering online from Morris, but just wanted to see if this was in fact the correct P/N, and if it happened to cross to something else.

My old mangled spline seal shows in the image below...


Thanks in advance for any thoughts --

David

[djm3452004]

Hi all --

Not trying to resurrect an old thread, but can anyone confirm the spline seal P/N listed at the Morris 4x4 site is the correct spline seal for the NP129 transfer case output shaft(s)?

Crown Yoke Washer Seal, P/N 4210973

https://www.morris4x4center.com/washer-front-yoke-rubber-4210973.html?utm_source=google&utm_medium=productfeed&utm_campaign=cse&gclid=Cj0KEQiAu_GmBRDhtK-kzqKcuJwBEiQAJvB8nzqhIj-tKBl9LxxNQKdYgB1taI2ZLVBpvVPdG5NJ4NgaAmtm8P8HAQ


Is this the only place to get this?  I've checked all the usual parts houses and this P/N does not seem to cross to anything, nor do they list any such spline seal as required.  I don't mind ordering online from Morris, but just wanted to see if this was in fact the correct P/N, and if it happened to cross to something else.

My old mangled spline seal shows in the image below...


Thanks in advance for any thoughts --

David

And to add to my confusion, the parts list for an '83 NP129 transfer case in Epedia lists P/N 8130815 as a "washer-seal" for this output shaft spline seal, and appears to show the seal under the yoke nut (Item #41), whereas my mangled seal (rubber only, no washer) from my NP129 above was under the yoke itself.

The two seal P/Ns I've listed in these two posts (Crown 4210973 and Crown 8130815) look virtually the same to me, but the 8130815 is listed as correct for the NP219/208/228/229 with no reference to the NP129.


Yep, definitely going to need some assistance on this one if anyone can (hopefully) chime in.


Thanks again!
David

[whiteeagle]

Hi David

I started this post back in 2015 with the same problem.

I clicked on the morris 4x4 link and I don't see any image to confirm its the right seal. Your worn out seal is exactly what my problem was and replacing it solved the my leak problem. Here's the company I got mine from.

https://www.4wheelparts.com/p/crown-automotive-transfer-case-output-shaft-seal-washer-j8130815/_/R-BKMN-J8130815

Its the same for a jeep check it out.

Good luck
Pierre
 

[djm3452004]

Hi David

I started this post back in 2015 with the same problem.

I clicked on the morris 4x4 link and I don't see any image to confirm its the right seal. Your worn out seal is exactly what my problem was and replacing it solved the my leak problem. Here's the company I got mine from.

https://www.4wheelparts.com/p/crown-automotive-transfer-case-output-shaft-seal-washer-j8130815/_/R-BKMN-J8130815

Its the same for a jeep check it out.

Good luck
Pierre

Thank you for that input, that was exactly what I needed. 

So does the rubber spline seal go under the nut only, or under the yoke itself?  The spline seal on my car was located under the yoke.  I had seen from previous owner documentation on my car that the output shaft seal was replaced in 2015, but I'm betting the reason it was still leaking was the seal was placed under the wrong component!

Do you (or anyone) remember the order of assembly for the spline seal?  Thanks in advance!

David

[AMC of Houston]

The spline seal goes under the nut (keeps fluid from escaping from between the splines).  The other big lip seal goes under the flange (seals on the smooth part of the shaft).

[djm3452004]

The spline seal goes under the nut (keeps fluid from escaping from between the splines).  The other big lip seal goes under the flange (seals on the smooth part of the shaft).

Thank you for your reply, things finally coming into focus!

Last question (I hope) -- is there a steel washer that is supposed to be used under the nut, and over the spline seal?  Mine had no steel washer at all, but I'm not surprised considering the incorrect placement of the spline seal to begin with.


Thanks again --

David

[whiteeagle]

The rubber seal(#41) goes under the nut. No steel washer.

See Epedia image in your earlier post

[djm3452004]

The rubber seal(#41) goes under the nut. No steel washer.

See Epedia image in your earlier post

Understood, thank you!  I did understand the exploded view, but what is in a mfgr's. drawing and what works are sometimes (2) different things.  Since you've done what is pictured and it works, I'm good to go.


Thanks again!
David