[CharlieCherokee]

Hey all, i just got back from a wheeling trip only to break down in the parking lot at my buddies shop.

Ive got a 1992 4.0l XJ with NP231 transfer case.

It all started when i was doing a hill climb in 4lo. All of a sudden, the car just went right into neutral. Thought my transmission was gone until i looked down and saw it had shifted itself OUT OF 4LO and was resting between 4lo and nuetral. I tried to put it back in 4 lo but it wouldnt move that last little bit to lock in. I got down to the bottom of the hill and this time it wouldnt move much past nuetral.

So anyways i just wheeled the rest of the time in 4h (which worked fine).

Then i got to my buddies shop and had him drive it to see if we could get 4lo engaged and he got it to "lock" but it wasnt down as far as where it usually locks into for 4lo. Anyways he takes it around the block and comes back with it grinding and making a screeching noise. I guess he lost power. And now i can sit in park, reverse, neutral, drive, 3, 1-2, and IT WILL NOT MOVE. you can almost hear them engage but the car will not move in 2h, 4h, or 4lo. You can almost hear a grinding noise when you rev the engine.

Some symptoms leading up to this were that i would get the occasional grinding noise in 4h and 4lo. i thought it was from making a turn too hard and was just something binding up. Also when my trans case was in neutral and i put my car in drive it would still move (shouldnt it be completely in neutral?). also whenever i was in 4wd, like 4hi or 4lo i would always have the "part time" light illuminated. If i was in 4lo shouldnt "full time" have be illuminated instead? Yet, i was definitely in 4lo because i could tell the car was definitely more torque and wouldnt go fast. Also it took a long time to shift between gears in 4lo (not sure if this has anything to do with it).

So the guys at the shop said i snapped the chain, it binded up and broke teeth on the gears on both sides and thats why its completely dead in the water.


Is it possible this is a vacuum issue? Any help / input would be appreciated. Worst case ill be pulling the driveshafts tomorrow and draining the fluid tomorrow and see if any metal teeth from the gears come out. If it is indeed the chain and teeth should i just get a rebuild kit / order the parts i need or just get a whole new one from the pick n pull? OR go with the tera low 4:1 rebuild kit?

[Paradise XJ]

A 92 doesn't involve vacuum to operate the t- case.

First reading I'd say adjust the linkage but if you broke a chain, that's out. Repairing/rebuilding/upgrading is always an option, but if it's toast, I'd hit CL or the JY for a used one.

I pulled a t-case from the JY in about 45 minutes for $75. That's what I'd recommend.

You'll need 9/16" box and socket, 15mm and 18 mm sockets at the yard FYI

[CharlieCherokee]

Originally Posted by Paradise XJ

A 92 doesn't involve vacuum to operate the t- case.

First reading I'd say adjust the linkage but if you broke a chain, that's out. Repairing/rebuilding/upgrading is always an option, but if it's toast, I'd hit CL or the JY for a used one.

I pulled a t-case from the JY in about 45 minutes for $75. That's what I'd recommend.

You'll need 9/16" box and socket, 15mm and 18 mm sockets at the yard FYI

yea would you suggest grabbing one off a cherokee or going for one of the "heavy duty" ones that came on some of the k5's or whatever else they came on?

[DerMeister]

Did it get driven on pavement in 4HI or 4LO?

[CharlieCherokee]

Originally Posted by DerMeister

Did it get driven on pavement in 4HI or 4LO?

not initally. when it popped out of 4lo i was doing a black diamond hill climb. When i got home at my buds shop he drove it on the pavement in what we thought was 4lo but was like inbetween nuetral and 4lo.

[DerMeister]

Originally Posted by CharlieCherokee

not initally. when it popped out of 4lo i was doing a black diamond hill climb. When i got home at my buds shop he drove it on the pavement in what we thought was 4lo but was like inbetween nuetral and 4lo.

Popping out of 4LO could have simply been from your linkage needing adjusted.

You're not supposed to use 4x4 on.dry pavement with the np231. That may be what wrecked it.

[CharlieCherokee]

Originally Posted by DerMeister

Popping out of 4LO could have simply been from your linkage needing adjusted.

You're not supposed to use 4x4 on.dry pavement with the np231. That may be what wrecked it.

honestly i dont think it was the linkage. it had been just fine the rest of the trip. that whole trip id been getting a lot of mysterious "grinding" and im pretty sure that had something to do with it.

it may have been super weak anyways and driving on pavement finally killed it.

[rugsucka]

Driving a 231 on pavement will stress your axles and ujoints creating wheel hop and binding. It will not likely damage the tcase.

[CharlieCherokee]

Originally Posted by rugsucka

Driving a 231 on pavement will stress your axles and ujoints creating wheel hop and binding. It will not likely damage the tcase.

i agree

[CharlieCherokee]

OK well i drained the fluid just now. Hardly any came out, probably half a cup (should hold a litttle over a quart). and what little that came out was BLACK. nasty old fluid thats probably never been changed. well thats what i get for not checking / replacing all the fluids. Almost have it fully removed though

[RacerX]

Originally Posted by CharlieCherokee

Hey all, i just got back from a wheeling trip only to break down in the parking lot at my buddies shop.

Ive got a 1992 4.0l XJ with NP231 transfer case.



also whenever i was in 4wd, like 4hi or 4lo i would always have the "part time" light illuminated. If i was in 4lo shouldnt "full time" have be illuminated instead? Yet, i was definitely in 4lo because i could tell the car was definitely more torque and wouldnt go fast. Also it took a long time to shift between gears in 4lo (not sure if this has anything to do with it).

Actually that was correct.

Part time is ONLY for off-road (or deeper snow), Full time is for pavement e.g. rain, snow, or you need more traction, or whatever.

[CharlieCherokee]

Ok hopefully someone can answer my question on this but i am looking to buy a used transfer case. I know that there are differences in spline count between ax15 and aw4. HOWEVER, ive also read there are differences in shaft input length.

My main question is, can i just take my destroyed transfer case and swap the input shafts assuming my new transfer case differs in spline count or length? Like if the tc is off of an ax15 and i swap the shafts will it bolt right up to my aw4 transmission????

Also, how difficult of a job is this? I read somewhere it takes 20 minutes... however i was also told it takes 45 minutes to get a transfer case out... Its ended up taking me more like 2-3 days.

[RLE]

You probably can swap the input shafts. We put a shaft for an AX5 into the TC for an AX15 and it works fine. My mechanic had to take all the guts out of the TC to get at the input shaft.

But you don't really need to do all that. If you are looking for a used NP231, it would seem to me there would be a lot more automatics than AX15s in the junkyards.

[CharlieCherokee]

Originally Posted by RLE

You probably can swap the input shafts. We put a shaft for an AX5 into the TC for an AX15 and it works fine. My mechanic had to take all the guts out of the TC to get at the input shaft.

But you don't really need to do all that. If you are looking for a used NP231, it would seem to me there would be a lot more automatics than AX15s in the junkyards.

yea but it took me 3 days to get my transfer case out. sorry i must be a newb then. i had been told it would take 45 minutes. I just dont think id be able to get it out at a junkyard without my whole garage of tools there

[RacerX]

BTW, I don't believe a NP231 has Part Time on the shifter.
My NP242 Does have Part Time

You may want to check this out and verify your Transfer case before deciding what to pull at the junk yard
FYI.