Yet ANOTHER transfer case thread! Hah! -
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post #1 of 8 Old 05-31-2013, 10:10 AM Thread Starter
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Yet ANOTHER transfer case thread! Hah!

Hi everyone, I'm Tommy and new to this forum. Seems I'm having some issues with my NP-231 Tcase that I could use some input on. I'm VERY mechanical and intend to tackle this project on my own... so here's what's up:

My problem is with 4WD engagement and operation. Basically the Tcase linkage moves as it should in all positions and I believe it is properly adjusted. Low range and high range both work properly but the 4WD doesn't always engage when it should be! When I bring it down to 4-low and enter the mud/sand slowly... most of the time only the back tires turn. If I slightly "blip the throttle", there will be a tiny bit of grind and the front tires will start to grab. This usually works in 1st or second gear in low range blipping just off idle. If I try in any higher gear with anymore throttle... she just grinds. If I enter a hole nose down, it rarely will engage at all. If I'm exiting nose up, it is much more prone to give me 4WD. It almost NEVER gives me 4WD in reverse. The problem is definitely in the case and NOT related to the front disco. Sometimes under deceleration it will pop out of 4WD on the trails with a small bang/pop noise.
So there it is! Any ideas from the experts here? I suspect a fork issue.... what's your thoughts?


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post #2 of 8 Old 05-31-2013, 10:32 AM
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Sounds to me like your CAD is acting up. It works off of a vaccum switch located in your tcase. It could be a vaccum leak, CAD on its way out, or a bad switch in the tcase.
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post #3 of 8 Old 05-31-2013, 10:58 AM
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First off, welcome to the forum!

What is it that makes you so sure that your problem isn't in the disconnect? From our description it sounds like a fair candidate. When I rebuilt mine (TC) the pads were worn on the fork and it didn't cause the issues you describe. Why not just lock the fork over in your cad and see if your troubles go away. Much easier than dealing with a potentially unnecessary TC rebuild.

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post #4 of 8 Old 05-31-2013, 11:00 AM
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post #5 of 8 Old 05-31-2013, 11:24 AM
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X4 on checking the cad.
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post #6 of 8 Old 05-31-2013, 11:28 AM
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didn't look at teh links provided but if you want to give yourself some peace of mind about the TC, put it in 4wd and have someone look to see if the front driveshaft turns when you move. My understanding (right or wrong) is that if you are in 4wd, it will turn, if not, it won't....

That being said, put me down for x4 on the CAD....

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post #7 of 8 Old 05-31-2013, 12:09 PM
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Some good reading for ya

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post #8 of 8 Old 06-01-2013, 03:27 AM Thread Starter
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Thanks everyone for the responses. The fork in the CAD up front has been locked via moving the snap rings. I have tried everything relating to that and it works with vacuum switch, but I have slid the fork over anyway. nylon pads are also good on the CAD fork.
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