Author Topic: np231  (Read 2173 times)

gearhead1985

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np231
« on: July 13, 2009, 01:45:57 AM »
i have 2 np231's for sale one off a 1994 cherokee and the one currenly in my 1992 wrangler the one in the wrangler will come out sometime in the future when i swap it out for my dana 300 i just bought off ebay

PaulW

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Re: np231
« Reply #1 on: July 13, 2009, 01:53:13 AM »
Give ya a buck.

Offline Axle

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Re: np231
« Reply #2 on: July 13, 2009, 01:45:34 PM »
Come on, Paul!  The NP-231 is a solid t-case.  The gear ratio isn't the greatest, but if you're riding on anything less than 40's, your good. 

Take your dollar and buy me a cup of coffee!  ;D
Axle:  2
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I win!

Offline kirksjeep

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Re: np231
« Reply #3 on: July 13, 2009, 03:38:15 PM »
Come on, Paul!  The NP-231 is a solid t-case.  The gear ratio isn't the greatest, but if you're riding on anything less than 40's, your good. 

Take your dollar and buy me a cup of coffee!  ;D

I agree with Justin, the NP231 is a pretty good transfer case, and can be upgraded relativiely cheap.  Thicker chain from a S-10 version, 2wdLO kit and even a 4:1 and you will have less $$$ into it then an Atlas or a built D300.

My question is:  Where do you get a cup of coffee for only a buck???? ;)
1992 YJ Sahara, 4.5 Rubicon Express ED Lift, 35" BFG MT, Custom Bumpers, SYE/CV Drive Shaft, OBA, Ford 8.8 rear, 4.10 gears, tie rod flip, 1"MML/BL
2002 KJ Liberty, 2" Lift, 31" tires/DD
2002 F-150 Harley Davidson 5.4L SC
2013 Explorer Sport
2006 Harley Road King Classic
1988 Honda Hawk GT

PaulW

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Re: np231
« Reply #4 on: July 15, 2009, 03:13:53 PM »
Come on, Paul!  The NP-231 is a solid t-case.  The gear ratio isn't the greatest, but if you're riding on anything less than 40's, your good. 

Take your dollar and buy me a cup of coffee!  ;D

I agree with Justin, the NP231 is a pretty good transfer case, and can be upgraded relativiely cheap.  Thicker chain from a S-10 version, 2wdLO kit and even a 4:1 and you will have less $$$ into it then an Atlas or a built D300.

My question is:  Where do you get a cup of coffee for only a buck???? ;)

I've sheared the front ouput shaft off one, sent a chain through the case of a second, and stripped the planetaries for 4 low in a 3rd.  They're not that strong.  I wonder how my zuki case is going to hold up??

Offline kirksjeep

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Re: np231
« Reply #5 on: July 15, 2009, 04:37:38 PM »
Come on, Paul!  The NP-231 is a solid t-case.  The gear ratio isn't the greatest, but if you're riding on anything less than 40's, your good. 

Take your dollar and buy me a cup of coffee!  ;D

I agree with Justin, the NP231 is a pretty good transfer case, and can be upgraded relativiely cheap.  Thicker chain from a S-10 version, 2wdLO kit and even a 4:1 and you will have less $$$ into it then an Atlas or a built D300.

My question is:  Where do you get a cup of coffee for only a buck???? ;)

I've sheared the front ouput shaft off one, sent a chain through the case of a second, and stripped the planetaries for 4 low in a 3rd.  They're not that strong.  I wonder how my zuki case is going to hold up??

What kind of drive train were you running to do all that damage.  I've seen guys run them behind a 350 SB and NV4500 with no problems.  Since they are chain driven, the chain can strech over time and possible need to be replaced, but I have never heard of one breaking off.  I know the transfercases in the 87 wranglers (I don't remeber the name of them) were crap, but the NP231 is a much better case.  Jeep has been using them for over 21 years now.
1992 YJ Sahara, 4.5 Rubicon Express ED Lift, 35" BFG MT, Custom Bumpers, SYE/CV Drive Shaft, OBA, Ford 8.8 rear, 4.10 gears, tie rod flip, 1"MML/BL
2002 KJ Liberty, 2" Lift, 31" tires/DD
2002 F-150 Harley Davidson 5.4L SC
2013 Explorer Sport
2006 Harley Road King Classic
1988 Honda Hawk GT

PaulW

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Re: np231
« Reply #6 on: July 16, 2009, 06:24:27 AM »
Come on, Paul!  The NP-231 is a solid t-case.  The gear ratio isn't the greatest, but if you're riding on anything less than 40's, your good. 

Take your dollar and buy me a cup of coffee!  ;D

I agree with Justin, the NP231 is a pretty good transfer case, and can be upgraded relativiely cheap.  Thicker chain from a S-10 version, 2wdLO kit and even a 4:1 and you will have less $$$ into it then an Atlas or a built D300.

My question is:  Where do you get a cup of coffee for only a buck???? ;)

I've sheared the front ouput shaft off one, sent a chain through the case of a second, and stripped the planetaries for 4 low in a 3rd.  They're not that strong.  I wonder how my zuki case is going to hold up??

What kind of drive train were you running to do all that damage.  I've seen guys run them behind a 350 SB and NV4500 with no problems.  Since they are chain driven, the chain can strech over time and possible need to be replaced, but I have never heard of one breaking off.  I know the transfercases in the 87 wranglers (I don't remeber the name of them) were crap, but the NP231 is a much better case.  Jeep has been using them for over 21 years now.

i built a HD 231.  dodge uses a 231 in the 1500 ram.  i used the internals just like JBCONVERSIONS to make a hd 231.  the front output sheared right off yolk and all flush with the t/case housing.  so that's 1.



  i snapped a chain in a 93 231 just by pulling a 3/4 ton ford out of the mud. that's 2



 the gears in the last was for 4low and was stock and just wheeling with sawzall fenders and 31's.


i can elaborate on any one, just ask....  231's just aren't that strong.

Offline kirksjeep

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Re: np231
« Reply #7 on: July 16, 2009, 08:16:53 PM »
Here is a thread I saved a while back about the NP231. 
http://www.pgh-offroad.com/forum/showthread.php?p=89437
There is some great stuff about using the Chevy and Dodge versions to beef up the Jeep version.  There are a few actual facts in the write up like the NP231 can handle 1940 ft/lbs of tourque!!!! and the NP242 is in the 1400ft/lb range.  Out of 25+ posts, the only chain breakage was a worn out chain.  There are a few guys that managed to explode them, but under pretty stressfull situations, but the D300 are known for exploding under high stress situations. 

For the $$$ I don't think the NP231 can be beat( my opinion).  If I had the $$$ I would put an atlas in, but then the t-case would be worth almost as much as the rest of my Jeep ;).  For the trails we run, I don't see any NP231 t-cases breaking unless something else like a busted spring/ control arm/ rock etc... causes it to break. 

By the way the avitar for post 25 and 26 are worth checking out even if you don't care about the NP231 ;)

By the
1992 YJ Sahara, 4.5 Rubicon Express ED Lift, 35" BFG MT, Custom Bumpers, SYE/CV Drive Shaft, OBA, Ford 8.8 rear, 4.10 gears, tie rod flip, 1"MML/BL
2002 KJ Liberty, 2" Lift, 31" tires/DD
2002 F-150 Harley Davidson 5.4L SC
2013 Explorer Sport
2006 Harley Road King Classic
1988 Honda Hawk GT

PaulW

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Re: np231
« Reply #8 on: July 17, 2009, 03:43:52 AM »
i'm curios to know how much abuse my suzuki will take...

gearhead1985

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Re: np231
« Reply #9 on: July 17, 2009, 04:36:48 AM »
i'm curios to know how much abuse my suzuki will take...

and what tcase are you planning on running

PaulW

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Re: np231
« Reply #10 on: July 17, 2009, 05:14:43 AM »
i'm curios to know how much abuse my suzuki will take...

and what tcase are you planning on running

supposidly when i bought the zuki it had a 6.5:1 low range kit in the stock case.  it says 33's are no problem, but i'm questioning that.