JB Conversions Heavy Duty NP231J

[threejeeps]

I've been looking at one of these as a cost-effective replacement t-case. Can't afford an Atlas, and I need to replace my current one due to a number of failing components.

Was wondering if anyone has experience/knows someone who has with one of these...

http://www.polyperformance.com/shop/...e-p-24843.html

[jackhammer]

If you can get jb go with it. I was on a 6month wait list. so I went with mega short sye. I got a 6pinion planetary from junkyard 241c. I got the wide chain and one wide hub from a 231d and the other hub?front output I got on ebay. Iyts not to hard tod and beats hell out of buying whole new case. invest in snap on snap ring pliers and goto a junkyard and start pulling tcases apart. Thats what I did and by time I had the parts doing mine was a snap

[jackhammer]

It starts at bottom of page 8 and goes to page 10 on my build thread

http://www.militaryjeepers.com/commu...-lt-5.2l/page8

[threejeeps]

Thanks, that's some good info.

[jackhammer]

sure....jb did eventually call me back when they had new shafts sent in but I was already driving jeep. They are a small company in the usa and was my first choice but I just couldnt be without my jeep any longer. Seems that they dont order new stuff till they are completely out. Not the most efficient way to run a buisness but hey whatever it takes to keep it in the usa

[highlandercj-7]

Go get a salvageyard case and save for the atlas, if that's what you want. That case is half the cost of an atlas and you still don't have a lower gear set in it.

[threejeeps]

Good call. I just need to find a good one with the right input shaft and swap my SYE over. Tax season is comin up, might be able to afford it then.

[jackhammer]

1 whats wrong with yours.
2 input shafts from other np tcases might work what trans and motor you have will depict what spline count and length you need

[FrankZ]

$1k for a 231J? NEVER!!
A rebuild kit will set ya back about $100.
SYE from JB Conversions is around $340
Junkyard parts
Wide chain and main gear from a 231C
Front output from a 231D
Build your own 6 planatary. Here's mine:
http://www.cherokeeforum.com/f2/shor...rite-up-34392/

[threejeeps]

Stretched chain, bearings all gone except for the one in the SYE tailhousing, and gears rounded on the edges/copious amounts of metal shavings on the drain plug. All my own fault. I swamped it one too many times when I didn't know you had to change fluids out, happy I'm not that dumb anymore... Almost three years smarter with Jeeps now, so I'll be able to take care of a replacement one a little better. Just found a salvage yard case for around $150, gonna go try to pull it and get the SYE swapped over on Saturday. Worst comes to worst I'll have to swap inputs, but I wanna wheel the damn thing again so I'm down for that.

4.0L and NV3550 5-spd btw.