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SYE question

CaliXJ

CaliXJ

NAXJA Forum User
Location
Oceanside, CA
I found a NP231 T case out of a 88-90 w/ a SYE on it. My jeep is a 91 with a NP231. From what i have read spline count on the input shaft changed 90-91. This t case will not just bolt in because of that. Now... Will the sye out of that (88-90) Tcase swap in my 91?

Looks to be an AA SYE.
 
Ok so i picked up this T case today and it has a 23 spline input on it. This thing should bolt right in to my 91 correct? Aslo whats the deal with the little vac. plug on the top? Has 4 black hoses coming out of it. Is that for a vac disco D30 and shift light?


Is it easier to leave my t case in and just swap over the sye?
 
Last edited:
Both parts. The vac hoses operate the vacuum disconnect. If it is 23 spline, it should bolt up just fine to your 23 spline output.
 
:cheers: Thanks

So it would be pointless to take the SYE out of the one to put in the on thats in my jeep? I've had another member suggest this is why i ask.
 
Last edited:
You should be able to change over the switch to where the vac line switch is now, so go for it. Just bolt it up. The only issue is the depth of the gear on the input. But there are only two depths. When you pull out the old one you will know. It doesn't take long to pull a case. If you do, it is much easier to change parts over with the case on a bench anyway.
 
4.3LXJ said:
You should be able to change over the switch to where the vac line switch is now, so go for it. Just bolt it up. The only issue is the depth of the gear on the input. But there are only two depths. When you pull out the old one you will know. It doesn't take long to pull a case. If you do, it is much easier to change parts over with the case on a bench anyway.
Click to expand...

There are actually 3 different input gears!
http://www.novak-adapt.com/knowledge/np_nvg_input_gears.htm
 
I ended up just swapping over insides. I didn't wanna run into the problem of diff input lengths. All seems to be good. Thanks for the help!
 
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