np231-dana 300 question

[blackd-out-chev]

ok...i have a 1988 jeep cherokee. 4.0/aw4/np231. i am starting to build it up and wanted to do a sye on it...then decided i might as well replace it with a dana 300 for almost the same price. well a little more money and i can do a box 4 rox/300. i picked up a 23 spline dana 300 the other day. well i was doing some looking around today and saw something that says pre 1991 aw4 transmissions have a 21 spline output. is this true? if so...what do i need to do? i am still not 100% clear on this whole setup, but for now this is my main concern.
so in short. 1988 xj 4.0/aw4/231 and a 23spline dana 300 tcase on the floor. what all do i need to do to run the box 4 rox/flipped 300?
thanks guys...sorry if its kinda newb questions. but i cant find the answers im lookin for on here, rockhardxj, or pirate.
Josh

 

[beakie]

the box for rox uses a 231 partial case doesn't it?
if so, the 231 front half will match up as if, and you match up the mid-shaft splines up with the D300

I think there is a thread on here, but here's another for reference

 

[the_weirdo]

User knucklehead_61 on (Sierra Chapter) has a 231/300 doubler that he is tearing apart right now. He can probably answer some questions if you PM him.

 

[tbburg]

Most D-300s are passenger-side drop. Jeep -231s are driver side drop. Unless you got lucky and have a driver side drop 300, you will also need to do a t-case flip on the 300 to bring it over, or get a new front axle.

 

[blackd-out-chev]

Duffys kit comes with(or appears to come with) a clocking ring...which would allow me to flip my case. Then either make my own flip kit or run cable sifters

 

[Redxj5150]

http://www.pirate4x4.com/forum/showthread.php?t=754931

check this one out on pirate. There was another I was looking for, and found this one. I'll keep searching for the flip flop 300 thread. forget what forum it was in...

 

[blackd-out-chev]

Thanks for the link...but I've already torn up the links in there and a lot of other places...I have the 300 flip sorted out. Now I'm just wondering about going from 21 spline from tranny into the 231 crawlbox. Then to 23 spline out of the crawlbox into the dana 300

 

[tonysinnette]

You should use the front input shaft (21 spline) from your 231 that you have, and I think the Duffy's kit should come with the correct intermediate shaft to join the crawl box with the 300. Madroster also makes a 231 D300 doubler kit.

 

[asp]

You should take apart your current 231, use its front half that's already mated to your aw4. You don't need the other 231 that you bought. The kit you get from DDMachine will have a spud shaft that goes from the front 231 output to the input of the Dana 300. The dana 300's 23 spline input gear has nothing to do with the 231's 21 spline input gear. If you're asking questions about all this stuff, get the whole kit - it'll run you $525 to your door.

For what it's worth, Phil (producer of the MadRooster kits) isn't producing and selling kits anymore. DDMachine is your best bet.

You'll need to flip the 231 and the 300. The 231's front chunk is too long for a driveshaft to clear it. There are a few threads on pirate about flipping a 300. If you just use cable shifters, prepare for leaks.

Hope that helped.

Edit:

ALL D-300s are passenger-side drop. Jeep -231s are driver side drop. Unless you got lucky and have a mythical factory 4:1 driver side drop 300 with 32 spline outputs and digital VSS, you will also need to do a t-case flip on the 300 to bring it over, or get a new front axle.

FTFY

 

[blackd-out-chev]

I have been trying to find a for sure answer on this... do I have to flip the 231 and the 300 if I'm going to be running it in a driver side drop application? If so why is it that way and how do I flip the 231?

 

[beakie]

the 231 is already driver side drop... bolt it up as normal, the 300 will need to be flipped for driver side drop.

silly question, but are you researching and reading about this, or just asking questions whenever you get stuck? there are quite a few, and rather in depth, threads/pages on how to do this which will walk you through what you want to do.

 

[jmaxj]

the 231 you'll need will have to be a 90 and older unless you want to swap transmissions or trans output shafts, and you will have to flip the crawlbox(231 ) to the pass side and the 300 to the driver side, that way you'll clear the driveline and such.
to flip it just mount everything upside down it all bolts up as it would normal.
hope this helps

 

[asp]

You don't need to do anything special to flip the 231. Just mount it so that the chunk is towards the passenger side. Reason for flipping the 231 is to allow the front driveshaft to clear the 231 case as it goes to the D300.

 

[blackd-out-chev]

Ya...I've been reading a crapload...the problem with that...is there is a lot of things that are conflicting just like in this thread. One person says yes. One says no. Etc. I just like to make sure I have a good handle on what I'm doing before I dig into it.

 

[jmaxj]

Ya...I've been reading a crapload...the problem with that...is there is a lot of things that are conflicting just like in this thread. One person says yes. One says no. Etc. I just like to make sure I have a good handle on what I'm doing before I dig into it.

well i've done it to mine, its not the easiest but its not to complicated either you will need to cut a hole in your trans tunnel also

 

[DesertRatRon]

Where would buy one of these said doubler kits??

 

[jcshaney]

Holly dead thread . This thread is from 2010