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NP231 Problems, '97 TJ

I'm having some odd noises while driving around that sound like a worn brake pad grinding against the rotor. There's also a bit of what I can only think to describe as a rotational sound ('chup chup chup') that's seeming to be only half as fast as the tires are moving (making me think drivesahft or the like). When I pull or push slightly on my transfer case shift lever while in

2wd, it intensifies ALOT. I don't think the noise goes away while in 4wd h/l, but if someone thinks it's relevant i'll confirm on my next drive.

What the hell is wrong here? Is my transfer case about to shit the bed on me?

__________________ '97 TJ 4.0 A/T Alarm w/remote start PCW EMR050 15" wheels BFG AT T/A KO's 31x10.50 KC 46 series fog lights Front tow hooks Front bumper end-cap delete Banks Power Torquetube header Airaid drop-in replacement filter Alpine CD head unit Audiovox Sirius satelite radio tuner Uniden Beartracker BCT12 scanner Yaesu FT-2600 VHF Ham Radio

Reply to
Endo
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I have had 2 NP231 wear out the chains, and what happens there is the chain scrapes on the bottom of the case. I also had one 231 kind of explode on me.

John > I'm having some odd noises while driving around that sound like a worn brake

Reply to
John in Vegas

Could I crack it open and replace the chain or is there more to it than that?

Shawn

Reply to
Endo

Reply to
L.W.(ßill) Hughes III

Search the net, there is a chain from a ford or a chevy? that fits the np231 and is stronger and bigger. Nick

Reply to
Nick N

I don't recall any rust other than the normal surface rust on everything. I'll check tomorrow in the daylight again to be sure. I saw the pic with the chain in it and how it fit in there. How could it be rubbing anything? Does it stretch? I did try it in 4wd earlier today and it seemed to act the same way, with any pressure up or down on the shift lever causing a stronger grinding sound. Man I just hope it doesn't explode like the one dude just said his had done.

Shawn

Reply to
Endo

Reply to
L.W.(ßill) Hughes III

How does applying pressure on the shift lever work into your diagnosis?

Shawn

everything.

Reply to
Endo

I have the same problem and have been putting off replacing the stretched chain. For sanity's sake, does the chain engage(turn) when only driving in 2 Wheel High?

Reply to
pauley

I had this same thing happen in my '99 TJ and it was the rear differential going from towing too much weight. After a few days, the chup-chup sound started sounding like an M-60 (really fast, loud popping at highway speed) and I took it in. Blown diff.

Thanks, Matt

Reply to
Matt

Reply to
L.W.(ßill) Hughes III

Mine exploded from trying to climb a rock ledge that I shouldnt have tried.

John > I don't recall any rust other than the normal surface rust on everything.

Reply to
John in Vegas

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