NAXJA Forums -::- North American XJ Association  

Go Back   NAXJA Forums -::- North American XJ Association > NAXJA Unibody Jeep Technical Forums > Jeep Cherokee XJ (1984 - 2001) > Modified Tech Discussion
HOME Member FAQ Sponsor Info Rules Bylaws E-Mail

Modified Tech Discussion Forum for Tech related discussion for Modified XJ's and MJ's.

Reply
 
Thread Tools Display Modes
  #16  
Old June 10th, 2018, 11:26
RCP Phx RCP Phx is offline
NAXJA Forum User
 
Join Date: Mar 2003
Location: Phoenix,Az
Posts: 11,164
Re: NP231 Black Fluid.....

I thought the XJ's didn't come out with a 231 until '88? Are you sure about what you have?
Reply With Quote
  #17  
Old June 10th, 2018, 12:56
burntkat burntkat is offline
NAXJA Member #1145
 
Join Date: Apr 2003
Location: Charleston, SC
Posts: 1,158
Re: NP231 Black Fluid.....

Quote:
Originally Posted by RCP Phx View Post
I thought the XJ's didn't come out with a 231 until '88? Are you sure about what you have?
They didn't come with an LS motor, ever.... Sooooo... Not sure where you're going, here..
__________________
-89 S-10: SAS, D44s front/rear. 5.7L V8. 700R4 with 4L60E upgrades. Built in my driveway.
-90 XJ 4.0, AW4, 231J: Clayton's longarms, RE 5.5" coils, hybrid 6" leaf pack, 33/12.50/15" MTs, Rancho 99012s and 99624s, Tera HD SYE, custom sliders, BW flares. Rehabbing with D44s, RE spring packs, RE 4.5" coils, and ACOS.
-94 ZJ: Budget boost, 31s. The wife's DD.
-97 XJ: Son's DD. 4" lift, ACOS, 4" spring pack, Upcountry coils, 31s
Reply With Quote
  #18  
Old June 10th, 2018, 20:25
clydefrog's Avatar
clydefrog clydefrog is offline
NAXJA Member
 
Join Date: Aug 2015
Location: Northern California
Posts: 456
Re: NP231 Black Fluid.....

Def an 231. Can't wait to pop her open and see the carnage and what failed.

So Moab 1, Jeep XJ 0. I bent my uni body so bad that the right rear quarter window doesn't seal, my tail light is busted and she didn't even make it home on her own power.....so yeah.

But, it was SOOOOO worth it. Moab is sick! Can't wait to go back. Gonna bring my own beer though that 3.2% bullshit is lame.
__________________
'87 with over 300k miles, and a CA legal LS swap.
Expedition built: http://www.naxja.org/forum/showthread.php?t=1129315

When you want to be someone you drive a lifted JK, when you already know who you are you drive an old XJ.
Reply With Quote
  #19  
Old June 11th, 2018, 08:13
burntkat burntkat is offline
NAXJA Member #1145
 
Join Date: Apr 2003
Location: Charleston, SC
Posts: 1,158
Re: NP231 Black Fluid.....

Quote:
Originally Posted by clydefrog View Post
Def an 231. Can't wait to pop her open and see the carnage and what failed.

So Moab 1, Jeep XJ 0. I bent my uni body so bad that the right rear quarter window doesn't seal, my tail light is busted and she didn't even make it home on her own power.....so yeah.

But, it was SOOOOO worth it. Moab is sick! Can't wait to go back. Gonna bring my own beer though that 3.2% bullshit is lame.
Man, sorry to hear about the carnage- it's a pretty truck. Wish I could see the pics!
__________________
-89 S-10: SAS, D44s front/rear. 5.7L V8. 700R4 with 4L60E upgrades. Built in my driveway.
-90 XJ 4.0, AW4, 231J: Clayton's longarms, RE 5.5" coils, hybrid 6" leaf pack, 33/12.50/15" MTs, Rancho 99012s and 99624s, Tera HD SYE, custom sliders, BW flares. Rehabbing with D44s, RE spring packs, RE 4.5" coils, and ACOS.
-94 ZJ: Budget boost, 31s. The wife's DD.
-97 XJ: Son's DD. 4" lift, ACOS, 4" spring pack, Upcountry coils, 31s
Reply With Quote
  #20  
Old June 11th, 2018, 10:20
kastein's Avatar
kastein kastein is offline
NAXJA Member
 
Join Date: Jul 2009
Location: Central MA - keep going till the road turns to dirt, then listen for banjos
Posts: 14,049
Re: NP231 Black Fluid.....

In for details on what happened. Only times I've damaged NP231s it was either low oil, seized front driveshaft centering ball, or misaligned parts.
__________________
My yard looks like Sanford & Sons.
Please do not PM me about the AW4 info thread unless you have a truly unique question that is not covered by it or info to add. I do not respond to questions answered by the thread.
Definitely do not hunt down my phone number at 3AM, text me about it, and then threaten violence when I am not helpful. It will not get you what you want.
CTeunuch: Sometimes I really wonder if this sport makes you insane, or it just attracts the mentally unstable.
Reply With Quote
  #21  
Old June 11th, 2018, 16:26
XJEEPER's Avatar
XJEEPER XJEEPER is offline
NAXJA Member # 13
 
Join Date: Aug 2002
Location: Wasatch Range
Posts: 8,962
Re: NP231 Black Fluid.....

Quote:
Originally Posted by clydefrog View Post
She blew!

I was on my way home and the transfer case went into neutral. Loud 'bang' then it was stuck in Lo range. This all happened 737 miles from home in Provo UT. Pulled the fill plug and this time there was metallic/black fluid (which I just changed roughly 300 miles ago in Moab). Luckily my father in law (who I was following) towed his TJ to Moab for wheeling, so we loaded my XJ up on the car trailer and used the TJ to tow my camper home to CA.

Gonna split the case open this week. My guess: something was dragging on the low range fork, 80 mph speed with a trailer it finally gave out. The 231 is the only stock component other than the D30. maybe it was a bit much, maybe I didn't rebuild it right 23k ago.

I will post updates with pics of the carnage once I get it apart. Just glad to be home, fun trip but Utah kinda sucked. Good scenery but backward laws that didn't make sense. Kinda glad to live in Cali.
Sorry to hear of your carnage......and I'm glad that you live in CA too! We need less folks moving to UT from CA to escape the high cost of living and Progressive policies, only to complain that UT isn't like CA........
__________________
Speak the Truth-Question with Boldness-Speak without fear.
Reply With Quote
  #22  
Old June 12th, 2018, 21:33
clydefrog's Avatar
clydefrog clydefrog is offline
NAXJA Member
 
Join Date: Aug 2015
Location: Northern California
Posts: 456
Re: NP231 Black Fluid.....

Ok pulled it apart today. The high/low range fork was completely cooked and there was aluminum pieces from it stuck in the pump pickup screen. I have been texting Blondjon to figure out the failure mode. So far everything looks ok. My guess is that the nylon bushings fell off or wore out which caused the noise, the heat and ultimately the failure. I took a pic and will post it tomorrow.

I just rebuilt it 23k ago when I put the 27spline input shaft in and the SYE. Gonna replace all the bearings, the seals, the planetary gears, slip gear for high/low and the shift fork. The selector shaft is spot on with no play so gonna leave that alone. The bearings seem all good but after running them in that nasty fluid I don't know. This rig sees 2k mile multi state trips regularly and I don't want to chance it. It's our overland rig. Breaking down 14 hours from home with my 4 year old and 4 week old was no fun, that's part of the adventure though!

The NP231 is the ONLY part on the jeep that is stock (other than the upgrades I did to it) maybe it just can't handle the LS? I don't know? Seems weird to have the nylon bushings fail, I don't want to miss anything......

Didn't mean to offend on the Utah comment, I'm just used to going to the gas station to grab a decent six pack and that was not an option in Utah. It was like a whole ordeal to get good beer.
__________________
'87 with over 300k miles, and a CA legal LS swap.
Expedition built: http://www.naxja.org/forum/showthread.php?t=1129315

When you want to be someone you drive a lifted JK, when you already know who you are you drive an old XJ.
Reply With Quote
  #23  
Old June 12th, 2018, 22:54
freerider15's Avatar
freerider15 freerider15 is offline
NAXJA Member
 
Join Date: Jan 2004
Location: FoCo, Crawlorado
Posts: 2,973
Re: NP231 Black Fluid.....

That seems like a lot of work for what I would not consider a questionable case.

If it were me, I'd pick up another 231, swap the SYE and be on my way.

Just my $0.02
__________________
XJ Buggy On Tons
Reply With Quote
  #24  
Old June 13th, 2018, 06:19
clydefrog's Avatar
clydefrog clydefrog is offline
NAXJA Member
 
Join Date: Aug 2015
Location: Northern California
Posts: 456
Re: NP231 Black Fluid.....

Quote:
Originally Posted by freerider15 View Post
That seems like a lot of work for what I would not consider a questionable case.

If it were me, I'd pick up another 231, swap the SYE and be on my way.

Just my $0.02
If I got another case I would prob want to rebuild it as well. It's only like $500 in parts to rebuild mine. If I did go the new case route what's a good source? I would also have to swap over the inner planetary (input shaft) gear so it would mate to my 4l60e trans. It's 27 spline.
__________________
'87 with over 300k miles, and a CA legal LS swap.
Expedition built: http://www.naxja.org/forum/showthread.php?t=1129315

When you want to be someone you drive a lifted JK, when you already know who you are you drive an old XJ.
Reply With Quote
  #25  
Old June 13th, 2018, 07:01
burntkat burntkat is offline
NAXJA Member #1145
 
Join Date: Apr 2003
Location: Charleston, SC
Posts: 1,158
Re: NP231 Black Fluid.....

I'd be looking into the feasability of a Chevy NP231 variant. They used a wider chain and cogs (but then, that doesn't seem to be what failed) and should bolt right to the 4L60E.
__________________
-89 S-10: SAS, D44s front/rear. 5.7L V8. 700R4 with 4L60E upgrades. Built in my driveway.
-90 XJ 4.0, AW4, 231J: Clayton's longarms, RE 5.5" coils, hybrid 6" leaf pack, 33/12.50/15" MTs, Rancho 99012s and 99624s, Tera HD SYE, custom sliders, BW flares. Rehabbing with D44s, RE spring packs, RE 4.5" coils, and ACOS.
-94 ZJ: Budget boost, 31s. The wife's DD.
-97 XJ: Son's DD. 4" lift, ACOS, 4" spring pack, Upcountry coils, 31s
Reply With Quote
  #26  
Old June 13th, 2018, 07:57
freerider15's Avatar
freerider15 freerider15 is offline
NAXJA Member
 
Join Date: Jan 2004
Location: FoCo, Crawlorado
Posts: 2,973
Re: NP231 Black Fluid.....

Quote:
Originally Posted by clydefrog View Post
If I got another case I would prob want to rebuild it as well. It's only like $500 in parts to rebuild mine. If I did go the new case route what's a good source? I would also have to swap over the inner planetary (input shaft) gear so it would mate to my 4l60e trans. It's 27 spline.
$500 is still a lot for an NP231.

NP231's don't fail very easy. If it were me, I'd find a decent mileage-ish NP231, crack it open and maybe replace the chain and shift fork pads. If the bearing looked good, I'd leave them.

With that kind of money...thought about looking into a different t-case all together?

Hell, that's halfway to a Rubi case just for the rebuild.

Since you're running an LS, I'd possibly look into something a little more HD.
__________________
XJ Buggy On Tons
Reply With Quote
  #27  
Old June 13th, 2018, 08:30
RCP Phx RCP Phx is offline
NAXJA Forum User
 
Join Date: Mar 2003
Location: Phoenix,Az
Posts: 11,164
Re: NP231 Black Fluid.....

Quote:
Originally Posted by burntkat View Post
I'd be looking into the feasability of a Chevy NP231 variant. They used a wider chain and cogs (but then, that doesn't seem to be what failed) and should bolt right to the 4L60E.
I would think were already talking about a 231C. It would cost a lot more to buy a adapter to go 4L60-231J.
Reply With Quote
  #28  
Old June 13th, 2018, 08:39
clydefrog's Avatar
clydefrog clydefrog is offline
NAXJA Member
 
Join Date: Aug 2015
Location: Northern California
Posts: 456
Re: NP231 Black Fluid.....

So if i don't do the planetary i'm looking at $200 ish (including a new oil pump, rebuild kit, shift fork and low/high slip gear). The planetary is another $200, may skip that since mine still looks decent.


Here is the shift fork:






Slip gear:




This is the input gear i got from advanced adapters and have been running, its 27 spline, still in awesome shape:
__________________
'87 with over 300k miles, and a CA legal LS swap.
Expedition built: http://www.naxja.org/forum/showthread.php?t=1129315

When you want to be someone you drive a lifted JK, when you already know who you are you drive an old XJ.
Reply With Quote
  #29  
Old June 13th, 2018, 09:57
XJEEPER's Avatar
XJEEPER XJEEPER is offline
NAXJA Member # 13
 
Join Date: Aug 2002
Location: Wasatch Range
Posts: 8,962
Re: NP231 Black Fluid.....

Quote:
Originally Posted by clydefrog View Post
Ok pulled it apart today. The high/low range fork was completely cooked and there was aluminum pieces from it stuck in the pump pickup screen. I have been texting Blondjon to figure out the failure mode. So far everything looks ok. My guess is that the nylon bushings fell off or wore out which caused the noise, the heat and ultimately the failure. I took a pic and will post it tomorrow.

I just rebuilt it 23k ago when I put the 27spline input shaft in and the SYE. Gonna replace all the bearings, the seals, the planetary gears, slip gear for high/low and the shift fork. The selector shaft is spot on with no play so gonna leave that alone. The bearings seem all good but after running them in that nasty fluid I don't know. This rig sees 2k mile multi state trips regularly and I don't want to chance it. It's our overland rig. Breaking down 14 hours from home with my 4 year old and 4 week old was no fun, that's part of the adventure though!

The NP231 is the ONLY part on the jeep that is stock (other than the upgrades I did to it) maybe it just can't handle the LS? I don't know? Seems weird to have the nylon bushings fail, I don't want to miss anything......

Didn't mean to offend on the Utah comment, I'm just used to going to the gas station to grab a decent six pack and that was not an option in Utah. It was like a whole ordeal to get good beer.
Glad you figured it out and I'm definitely not offended.
__________________
Speak the Truth-Question with Boldness-Speak without fear.
Reply With Quote
  #30  
Old June 13th, 2018, 12:43
TRCM's Avatar
TRCM TRCM is offline
NAXJA Member
 
Join Date: Jan 2007
Location: Newport News,VA
Posts: 1,079
Re: NP231 Black Fluid.....

I'm not so sure I would run the planetary if it has had that black contaminated fluid in it.

I'd at least flush the dog pee out of it.

It may look good, but who knows when it will decide it is done.
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
NP231 slip yoke lose fluid? Jeep450r OEM Tech Discussion 2 April 1st, 2012 20:10
Quick NP231 Fluid Question 4WDlifeform OEM Tech Discussion 25 March 11th, 2010 20:27
tcase fluid? np231, atf or gl4 or gl5 german996 OEM Tech Discussion 2 April 3rd, 2009 09:33
NP231 fluid (atf or gl5) question , please help german996 OEM Tech Discussion 16 September 13th, 2008 04:50


All times are GMT -7. The time now is 05:23.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
NAXJA and NAXJA logo's Copyright NAXJA. All content/images Copyright NAXJA 1999-2014