• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

NP231 rebuild/upgrade recommendations

About the different SYE kits ... I spoke with the guy who owns SBC OffRoad Engineering. They handle all of the online sales for PORC, and he said that *all* of the 231 HD SYE kits are pretty much the same. They all use parts from Taiwan, Korea, Japan, China, etc, and they all order those parts from the same suppliers.

The only difference is Advance Adapters. They manufacture their own tail housings (because that's what they do), but the internals of the kit are the same as the others.

Just some more info for anybody who's reading this.
 
I just got off the phone with a tech support guy at G2 (thanks for the recommendation, ehall). The G2 guy told me their 231 rebuild kit uses Timken Roller Bearings, Torrington needle bearings, and National seals. The kit also includes Gaskets, O-rings, fork pads, etc. -- he didn't know the brands, but if they paid the same attention to quality as the bearings, they should be good.

I know Timken and Torrington are both top-notch. As for National Seals ... I've used their axle & pinion seals in the past with no problems. Anybody have any comments on National?

Part numbers for G2 rebuild kits (NP231):
37-231 -- (for 87-94 w/24mm input bearing, $95.99 at Summit Racing)
37-231FF -- (for 94-06 w/16mm input bearing, $110.99 at Summit.)
 
Rebuild Kit: (Master or Partial) - http://www.jbconversions.com/products/np231j/rebuild.php

SYE: (Same kit everyone else offers) - http://www.jbconversions.com/products/sye/np231j_std_sye.php

Good thread on upgrading/rebuilding the 231 - http://www.pirate4x4.com/forum/jeep-non-hardcore/1503778-np231-full-upgrade-build.html



When I did all mine, I got a package deal from Tom Wood's. SYE + Driveshaft was ~$500 shipped. SYE kit was from Teraflex, but again it's the same kit everyone else has, and the custom cut & balanced shaft. I've been very happy with all the parts that I received. Also have the Boostwerks shifter (http://www.naxja.org/forum/showthread.php?t=1113419), and it worked flawlessly and easy to adjust. Much less work involved installing than the Novak

Tom Wood's:
http://www.4xshaft.com/XJCherokee.asp
http://www.4xshaft.com/SYE/AdvAdaptersHDkitandTeraFlex231conversions.html
 
I have the 242, which can be difficult to get lined up sometimes. Need to dial in the shifter using Full-Time and Neutral positions, then verify against the others. Also needed to notch the ends of the shift gate to give more travel so it wouldn't get bumped out of 4-Low on hits, and enough throw to get it into 2WD without hitting, but that was before changing to the BW shifter
 
After looking into the quality of various options, this is what I decided to go with:

Rebuild kit: G2 Axles
SYE: Advance Adapters
1.25 inch upgrade: http://www.ebay.com/itm/182465565737 (without the used chain).
Chain: Morse/Borg-Warner HiVo 1.25 inch chain HV-022
Shift linkage: Boostwerks

Thanks to everyone for the info. When the snow melts, I'll be able to start the rebuild. I'll try to do a write-up this Spring.
 
The front output shafts are the same!
 
Thanks for the info. The reason I asked about the splines was because I'm getting a 1.25 chain upgrade, which includes the front output shaft, and the sprocket on the rear output shaft. I just wanted to make sure the seller wouldn't send me a wrong-fitting part.

Thanks!
 
You must log in or register to reply here.

Similar threads

H
95 XJ Pulsing Vibration At Highway Speed
Replies
13
Views
4K
RCP Phx
R
K
Shop rebuilt front differential failed on first test drive, trying to figure out why?
Replies
4
Views
3K
xcm
xcm
X
What BRAND Tranny fluid and T-case fluid do you use? (AW4/NP231)
2
Replies
26
Views
3K
XJI6191
X
T
Can I rebuild this np231?
Replies
14
Views
1K
Skruffy
Skruffy
N
2000 XJ, high miles, lots of new parts, still have vibration
Replies
10
Views
1K
N8N_99xj
N
Back
Top