NP231C

Anyone running a Chevy version of the 231 in their jeep? This is what I am going to end up using in my V8 swap. Only problem is that the Blazer I stole this from had a electronic speedo and the XJ has a mechanical. I was thinking of trying to swap stuff over from the 229 that was in it but I can't find any info if it is possible. Would be nice too because the 229 had a fixed yoke.

I started looking into this and plans changed. I could be wrong but I believe it's clocked differently and the output shaft has less splines. I can't remember if that's what the big thing was or not. Someone was going to try and take both apart and see what kind of hybrid they could build but never heard anything else about it. Usually that means no-go.

I believe you can use some of the internals from the 231C. PM 2xtreme, he has done something along this line.

I just read my original post and realized that I never asked a real question. So, would it be possible to put the output shaft and tail housing from the 229 into the 231. I am not too worried about the t-case not mating to the trans since I am using the 700R4 from the blazer as well. Also, I don;t have to worry about the number of splines since, if the 229 parts don't work, I will be getting a SYE with HD shaft anyway. Either way, I need a tail housing that has provisions for a speedo gear to feed the mechanical speedo in the JEEP.

find a 231 out of an earlier s series with a mechanical speedo...this is exactly how i did the v8 swap in my xj...all chevy parts. easier and cheaper.

Troy, did you end up using the stock crossmember and trans mount from the Jeep, your donor vehicle or a custom job?

I have a 231C and 700r4 about to go into my jeep. From what I have heard, the C just has a different input. A buddy of mine has one in his blazer, and he told me he did not have to order anything special for the sye either.

...Smart choice and a good decision .Kudos and congratulations on useing the NP231C behind the Chev 700R-4 transmission-I am thinking that I might have made a mechanical misstep in hastily re-installing my NP229 after my own Chevrolet 350 V-8 engine swap-I ended up with haveing to get an clocking ring and a adapter to mate everything together-In hindsight I am thinking that a NP231C out of a Blazer would have been an easier and "natural fit"-I am sure the shorter lenght underneath would have been better-I also made/fabricated a custom crossmember out of 4"X6"-inch boxed mild steel useing my trusty plasma cutter-In any case I will be working the XJ and ole NP229 transfer case hard this upcomeing winter in some sorta gleeful anticipation of replaceing it with maybe one of those nice short JB NP231 conversions for X-MAS.

i used the stock crossmember with the chevy tranny mount. just had to drill two holes to bolt it fast. the earlier chevys had a 207 transfercase, but its the same tailshaft as the 231. find a mechanical speedo housing from a 231 or 207...jeep or chevy.in otder to use the jeep front driveshaft you also need to get the front yoke from the jeep transfer case...the 231 or 207.

Troy, I have all 4 drive shafts, the two from the jeep and the two from the blazer. IYO, wouldn't I be able to just use the blazer front shaft and re-use the jeep rear with the SYE since it is a slip shaft?

the front blazer shaft is way too short for the front. i ended up using stock driveshafts from a 4.0l... but i placed the driveline where i wanted it to allow for easy replacement of parts.

That's good to know. I am currently collecting parts and getting everything taken apart. I just bought a 3/4 ton Chevy truck that is going to donate it's motor and axles to the XJ. If I use the front D44 I am going to have to use the np205 from the truck as well. I haven't done any measuring yet, I got the truck for a really good price and can just sell the parts if I have to.
Would be nice to have the 14 bolt rear and D44 front in the jeep though. I need to get some measurements so I know how far they will stick out if I use them.

EDIT: I wonder if the front CV shaft from the truck will work as the rear DS in the XJ?

the chevy fullsize 4x4s are all right hand drop for the front output. to use the d44 you need to use the 205. that being said, the 205 is a much better transfer case anyways. all gear drive and cast iron.