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Unread 09-04-2011, 09:03 AM   #1
jgillespie
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1991 YJ Wrangler 
 
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NP231 strength

How much abuse will the stock xcase handle? I know it depends on a lot of variables, so here is what I plan for it.

Im beginning to save some cash for a lift and some 35's or 36's. It will be a largely daily driven and a weekender on the trails. I don't have a lead foot, but do eventually plan to plop in an SBC in the future. How do you think it will hold up to these kind of plans?



Jason

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Originally posted by Crazyquadder:
Quote:
a 6 foot puddle is approx half way up my doors
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Unread 09-04-2011, 09:06 AM   #2
Mark05059
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people are running np231 transfer cases with SBC currently. I would see no reason to worry about the transfer case before I worried about the rear axle you currently have.
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Unread 09-04-2011, 09:08 AM   #3
crb577
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worry about the 35 not the 231. the 35 will grenade long before the 231 will.
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4.0L Tom Woods rear HD shaft
D30 w/yukon alloys, lock right, jb4x4 bracket, Rusty's HD tie rod 8.8w/ LSD,SOA xj rear 100" wheelbase, homemade greasable boomerang shackles, SS braided lines, 1" prothane body lift, 35" TrXus M/T, smitty built XRC.
lots of gen right armor and rear stinger.
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Unread 09-04-2011, 10:54 AM   #4
jgillespie
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I know about the 35, that will be addressed too.

Thanks for the input

Jason
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'91 YJ 4.0 3/4'' Brandon Booms 31/10.50 BFG AT Herc'd CJ dash/tailgate CJ5 seats 4KCs cracked windshield
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Originally posted by Crazyquadder:
Quote:
a 6 foot puddle is approx half way up my doors
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Unread 09-04-2011, 11:20 AM   #5
leftlanetruckin
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I wheel on 37's with the 4.0, and a 4:1 kit inside the 231. Never had an issue with either this rig or any prior rigs that had the 231. I put them behind SBC's and 4.3 on a regular basis and never have issues.
Drop a 4:1 kit in it (4x4 group buy is the cheapest I found), a SYE, and go wheeling

Martin
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1998 XJ on 37's.JK Rubi axles with chromo shafts and ctm's, 4:1 transfer case, etc etc etc.The Cherylkee....
2003 Range Rover HSE, 4.4 Quad Cam.
1998 Range Rover 4.6 HSE
2000 4.7 4WD WJ with a rebuilt motor.
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http://www.jeepforum.com/forum/f12/swap-offically-underway-324622/

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Unread 09-04-2011, 11:26 AM   #6
hesserdude07
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i have a hybrid 231 behind on sbc, 35s (waiting on 37s) and a JB conversion SYE. Works great
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1993 Silver YJ. SBC 300hp. 700r4. NP231 hybrid. 35" Mud Terrains. 7" Toyota Basterd packs. 8.8 Welded. D30 loc-rite. 1" body lift. 4" LED tails. Custom bumpers. Warn M8000. Hella's. (Trail rig)
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Unread 09-04-2011, 12:55 PM   #7
jgillespie
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Quote:
Originally Posted by leftlanetruckin
I wheel on 37's with the 4.0, and a 4:1 kit inside the 231. Never had an issue with either this rig or any prior rigs that had the 231. I put them behind SBC's and 4.3 on a regular basis and never have issues.
Drop a 4:1 kit in it (4x4 group buy is the cheapest I found), a SYE, and go wheeling

Martin
I was thinking you may chime in on this. Thanks for the advice, I may go that exact route.

Jason
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'91 YJ 4.0 3/4'' Brandon Booms 31/10.50 BFG AT Herc'd CJ dash/tailgate CJ5 seats 4KCs cracked windshield
RED JEEP CLUB MEMBER 536

Originally posted by Crazyquadder:
Quote:
a 6 foot puddle is approx half way up my doors
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Unread 09-04-2011, 12:58 PM   #8
jgillespie
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Join Date: Oct 2007
Location: Dalton, Georgia
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Quote:
Originally Posted by hesserdude07
i have a hybrid 231 behind on sbc, 35s (waiting on 37s) and a JB conversion SYE. Works great
Sounds good. What parts did you use to frankenstein the 231 with?

Jason
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'91 YJ 4.0 3/4'' Brandon Booms 31/10.50 BFG AT Herc'd CJ dash/tailgate CJ5 seats 4KCs cracked windshield
RED JEEP CLUB MEMBER 536

Originally posted by Crazyquadder:
Quote:
a 6 foot puddle is approx half way up my doors
jgillespie is offline   Reply With Quote Quick reply to this message
Unread 09-04-2011, 06:04 PM   #9
leftlanetruckin
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Quote:
Originally Posted by jgillespie View Post
Sounds good. What parts did you use to frankenstein the 231 with?

Jason
Looking at his motor and tranny, I would think he went the route of 231c front half, 231j rear half.

Martin
__________________
1998 XJ on 37's.JK Rubi axles with chromo shafts and ctm's, 4:1 transfer case, etc etc etc.The Cherylkee....
2003 Range Rover HSE, 4.4 Quad Cam.
1998 Range Rover 4.6 HSE
2000 4.7 4WD WJ with a rebuilt motor.
4.3/700r4/new frame buildup (YJ)....
http://www.jeepforum.com/forum/showthread.php?t=324622

Years to gain the hands on experience, and offer it freely.
Minutes to gain the knowledge from the internet, and quote it just as freely.
Choose wisely!
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Unread 09-04-2011, 08:02 PM   #10
hesserdude07
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Location: Bloss, PA
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Quote:
Originally Posted by jgillespie View Post
Sounds good. What parts did you use to frankenstein the 231 with?

Jason
yep, 231c front case and wide chain kit. 231j rear case with JB conversions SYE. Works great...
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1993 Silver YJ. SBC 300hp. 700r4. NP231 hybrid. 35" Mud Terrains. 7" Toyota Basterd packs. 8.8 Welded. D30 loc-rite. 1" body lift. 4" LED tails. Custom bumpers. Warn M8000. Hella's. (Trail rig)
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