Pinion bearing? drive shaft? or transfer case?

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Feb 26, 2013 | 02:14 PM
  #1  
The specs...
1995 5-door Cherokee "Country"
4.0 in-line six
factory tow package
4x4 Automatic

NP242 - "Selec-Trac" transfer case

I recently had some problems with the front bearings. The front diff was hot and smoking. However, with help from you folks on this forum, I tested the front pinion bearing for side-to-side play, inspected the inner workings of the front diff, replaced the inner axle seals, and replaced the front bearings... twice... because I'd been too cheap to buy the Timkens in the first place.

The XJ ran great in 2wd for a while.

Then, last weekend, I put the jeep into 4wd and the XJ acted as tho the parking brakes had been left on. Accompanied with a low, grumbling whine sound. I shifted back into 2wd and got no change. It was so bad that if I took my foot off the gas pedal, the car would grind to a stop within 20 feet or so.

I figured it HAD to be the transfer case.

So, I removed the front driveshaft. And now I can drive the XJ around no problem. (Yes, I am fully aware that the '95 cherokee will role on an incline if the front drive-shaft is removed. With that in mind, I am religious in using the parking brake.)

Now, before I pull the transfer case for a rebuild. I have some questions..

Remember, I had a smoking front diff a while back there. Could the problem be in a binding pinion bearing?

Or, could bad u-joints in the front drive-shaft be enough to bring the 4wd to it's knees? I'm planning on replacing them anyway. After all, it's been over 225,000 miles.

And if I DO need to pull the transfer case for a rebuild... what tell-tale signs do you all suggest I keep an eye out for when I pull it apart?

I have the NP242 - "Selec-Trac" part-time OR full-time transfer case with shift pattern... 2wd - 4part-time - 4full-time - N - 4LO

I thank you in advance for your advise.
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Feb 26, 2013 | 03:13 PM
  #2  
i dont know all your symptoms but in my jeep the front DS was blown out, the double cardon was messed up and the ujoints were blown out aswell, after rebuilding the double cardon i dont get anymore grinding sounds
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Feb 26, 2013 | 03:26 PM
  #3  
Quote: i dont know all your symptoms but in my jeep the front DS was blown out, the double cardon was messed up and the ujoints were blown out aswell, after rebuilding the double cardon i dont get anymore grinding sounds
Yeah, I think that's the FIRST thing I'll do. Replace those u-joints since the drive shaft is just sitting in my garage anyways.

By the way, I found this WONDERFUL late-model, NP 242 rebuild thread on another forum. With detailed descriptions and lots of pictures.

Moderators... I checked the rules and didn't see any problems. However, if posting links to other forums is against the rules. Please feel free to remove this post.
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Feb 26, 2013 | 03:40 PM
  #4  
In 2wd you should be able to spin front yoke on transfercase by hand is this possible ?
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Feb 26, 2013 | 04:33 PM
  #5  
dunno, I'll crawl under tonight and try it.
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Feb 27, 2013 | 11:47 AM
  #6  
Got up at the butt-crack of dawn this morning and tested the front transfer case yoke. In park, and in 2wd... yes. It spins.

However, I don't think I'm out of the woods yet. I want to shift the XJ into and out of 4wd, reversing and going forward. THEN, crawl under and see if that yoke still spins. I'll try it tonight.
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Feb 27, 2013 | 12:31 PM
  #7  
Quote: Got up at the butt-crack of dawn this morning and tested the front transfer case yoke. In park, and in 2wd... yes. It spins.

However, I don't think I'm out of the woods yet. I want to shift the XJ into and out of 4wd, reversing and going forward. THEN, crawl under and see if that yoke still spins. I'll try it tonight.
this is good sign go ahead ancheck shifting . Then id jack up front axle set on jack stands and spin wheel and yoke.
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Mar 8, 2013 | 02:48 PM
  #8  
Thanks freegdr...

I drove the XJ up and down the street in front of my house. In 2wd it drives fine. But when I pop it into 4wdr, the drive train dissengages somewhere (the transfer case I expect) and the cherokee coasts to a stop. And while still in 4WD, I can rev the engine and hear the chain rattling and rumbling in the transfer case. Pop it back into 2WD and the car is drivable again.

Okay, looks like the transfer case is toast. I'm going to tear it apart and rebuild. What worrys' me is that i'll open the case and find sprockets with worn down and/or broken teeth. At that point, I think I'll find myself looking for a junkyard transfer case to use and maybe even rebuild.

Note: I've noticed a rumbling sound while driving for a couple of months... I realize now that I've been hearing the chain rattling and maybe even slipping.

I'll report back on what I find when I open the transfer case up.

By the way... I know there is supposed to be a round little tag that identifies the transfer case. Where does it live? I've crawled all over mine and haven't been able to locate any round id tags anywhere.

Based on the year ('95) and the shift pattern (2WD-4WDPART-4WDFULL-N-4LO) on my XJ, I'm pretty sure the TC is the NP242.

Thank you all for your comments.
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