Theryro

Hello Cherokee Forum! Very long time reader and user, however, this is my first post. First off I'd like to thank all of you for the help you've given me over the years, even without you knowing. Thus far I've been able to find a thread or post that has answered my questions/concerns. Buuuuuut..... Not this time. I know others have had a similar issue, then the thread goes dead. Here's what I've got going on:

Going to make a very long story short here.

Bought a 98 Xj Sport 4X4 AW4 NP231

Bell housing had a crack in it! A GIANT crack, the thing was broken in half.

Dropped the trans, replaced the bell housing. All seemed good, had a couple of vibrations still but nothing unusual for a Cherokee (this is my 4th).

Threw a 4.5" lift.. Got some terrible vibes.. think death wobble, but instead of it being the suspension, death wobble for the drivetrain. Found a giant ding in the driveshaft, thought it might have been bent or off balance. Replaced.

Still getting vibes. Pop off both drive shafts, throw it in D crawl under to see if I can find anything unusual.. Then my jaw hits the driveway. T-case mainshaft is bent. Great.
Drop the T-case; tear it apart, throw in a new (Free from a nice TJ owner who just did a SYE) mainshaft, seal it up. Bam!! Vibes are gone. Finally! She's drivable!

Now, all of these things probably came from one incident with the P/O. Maybe he slammed the driveshaft down on a boulder after jumping the jeep 20 feet in the air. I'll never know.

Now you know how everything happened, lets talk about my current dilemma.

Immediately after getting the t-case back together it starting leaking out of the rear output shaft seal. I chalked it up to a faulty install technique. Replaced a second time with a new seal this time taking extra care to be sure it goes on without incident. Leaks again, immediately. Okay, now whats going on? I pop the seal off and inspect it, the seal is chewed up. From what I can tell, it looks as if the snap ring on the shaft is rubbing on the seal and eating it up. So, get a new snap ring, throw it on, new seal. This time I drive it around maybe 50 or so miles without any issues. Yay its done! Nope. Sitting at a stop light and notice smoke pouring out from under the jeep. Sure enough. Rear output shaft seal. AGAIN.

Now I'm second guessing everything with the t-case and mainshaft.

This mainshaft runs perfectly smooth. It isn't bent.

There is a TINY amount of vertical play in the shaft. I'm talking 1/1000th of an inch. Can hear the movement but cannot see, nor can you really "feel" it. I'm thinking this is within the normal range.

One seal appeared to have been chewed up from the outside. The seal I just pulled off appears to be chewed up from the inside. I will post pics.

I apologize for the lengthy post, but I'm thinking the back story may be able to narrow down another potential issue that I might be missing.




Does this snap ring appear normal? It almost seems like it isn't fully grasping the notch in the shaft.



Here's a closer picture of the snap ring.



Front of the seal.



Rear of the seal.

CCKen

Are you using a Mopar seal, part number 4798117?


There should be a tiny garter spring around the lip of the seal that contacts the shaft, on the inner surface. I don't see one in your pic - of course it's all chewed up and may have dropped out.

Theryro

Yes there was a spring, it was dislocated from the seal. I'm using a seal from napa # NOS 18108

Theryro

I'm thinking of just going with a SYE to eliminate the problem, but I just don't want to drop and split the case again. I got that new shaft for free! I couldn't let it go to waste! Has anyone had this issue before? I'll be getting my 4th seal.

CCKen

Get one from the dealer, not an aftermarket seal.

Mopar seal, part number 4798117.

CCKen

I might be wrong but that output bearing inner race snap ring doesn't look like it's seated all the way.

Theryro

That's one thing I've been worried about, but I cannot get it to seat deeper. Any ideas? I was messing with it for quite some time trying to get it to seat all the way around. It IS grabbing it, but barely.

Theryro

Update: So I talked to a local jeep guy about my issue and he told me something interesting.. after describing to him what was happening to my seal we talked about the order in which the parts go on and now I'm getting conflicting information.

Here's how I've been installing it. After the snap ring holding the mainshaft to the bearing:

1. Output shaft seal
2. Snap ring
3. Oil slinger washer
4. Oil slinger/dust cover

He said he installs this way:

1. Oil slinger washer
2. Output shaft seal
3. Snap ring
4. Oil slinger dust cover


Everything I've researched has pointed me towards the way in which I have been installing it, expect for him. He said he installs them that way and has never had an issue.

CCKen

Here's the order of assembly. 231 and 242 the same.


I've overhauled my TC and had the **** end of another off and reassembled and used this order of assembly.



.

CCKen

That rear bearing I.D. retaining ring can be a PITA. You have to pull the main shaft out to free up tension on the snap ring and at the same time try to poke the snap ring in place with a screwdriver.


When done, polish off a 12 pack of beer.

Theryro

This is how I've installed it, it directly contradicts what this jeep place said. This place does SYE's very frequently. I wonder why he'd steer me in the wrong direction.

CCKen

Because he's a dud. Go by the FSM.

Theryro

Agreed.

Do you think it's possible that the retainer or the output shaft bearing could be the culprit here? I can't find any indication for that, but I just cannot seem to pinpoint what else could be the problem. I'm getting tired of purchasing $20 seals.

CCKen

The retainer ring may be sprung from trying to get it on. The FSM says reuse is not recommended.


You might trying installing a new retainer. Do not spread it too much getting it over the output shaft.


Mopar part number J8134488. The dealer should have it.


If the bearing is the correct one there shouldn't be a problem but......

CCKen

But...


If you think you need a new bearing I would suggest NAPA part number BRG 6206J.