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NP231 Diagnosis

Went wheeling my '87 YJ a couple weeks ago, pushed it a bit more than usual. Mostly dirt with some serious mud holes but no rocks to stress things. Managed to break the vacumn switch on the transfer case, fixed that, went to check out the 4wd. As soon as I put ANY load on the transfer case in 4wd, I got some NASTY 'bangs' from the trasfer case. Once a second, several times. Felt like something was not engaging right. Pulled the case, fluid was low, chain was very sloppy. Nothing else seems to be seems to be chewed up: front axle 'U' joints look ok, front axle disconnect dog looks fine, transfer case synchos look ok.

Question: would a loose chain give me the noise or should I look for something more?? The chain just barely misses the side of the case when pushed over.

Reply to
RoyJ
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Had same. Chain is stretched and is jumping on the sprocket. Check gears and replace if show wear. Replace chain. Replace all bearings. Failure to do this will result in catastrophic failure of the T-Case.

Reply to
reconair

Reply to
RoyJ

All I ended up doing with mine was replacing the chain, the input and output bearings and the shift mode fork. I let the fluid level get too low for too long. I put another 150K miles on it after the repair and eventually used it as a core trade for a REMAN with a SYE.

Reply to
reconair

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