Jeep JK transfer case NP/MP241

[TBItoy]

So the standard (non-Rubicon) JK 241 transfer cases are cheap and readily available, fixed yokes, 32 spline outputs.

Is the input interchangeable with a 27 spline or 32 spline GM NP241/243/246?

I know "back in the day" 231C/J/D NP241C/D mix and match building was pretty common and there is lots of info available out there, and I've messed with the 5 bolt s10 231C & 6 bolt 231J, I've just never laid hands on a JK case.

Looking around on the JK forums, it seems that everyone is set buying $500-700 adapters and swapping the transmission output shaft to 23 spline... which seems dumb -- And anytime a question is asked, the answer is always "Call shop xxx and throw loads of cash at it!". Plus they are all worried about speed sensor compatibility and making sure the dash lights up correctly.

 

[The Luke]

Following.

 

[TBItoy]

Following.

I may just have to buy one and check it out... currently the only NP tcase I have is a 27 spline 5 bolt NP231C (that is the front half of a old 231/Dana 20 doubler...)

I did read an old thread from 2011 where MOTECH was posting about modifiying a 32 spline NP241 input to go into a JK case to put behind a 4L80e. No real details, but it seemed like they needed to machine down a bearing surface or something. They were acting like it was a big deal, but that is them posting as a vendor doing "cutting edge" drivetrain swaps on new (at the time) vehicles.

Most of the info out there is either using a 6L80/90 trans (in which case they swap a 29 spline input into the JK case), or retaining the Rubicon 4:1 241, which requires swapping the trans tailshaft, as no other inputs are compatible with the 4:1 planetary.

 

[Otherway1970]

So the standard (non-Rubicon) JK 241 transfer cases are cheap and readily available, fixed yokes, 32 spline outputs.

Is the input interchangeable with a 27 spline or 32 spline GM NP241/243/246?

I know "back in the day" 231C/J/D NP241C/D mix and match building was pretty common and there is lots of info available out there, and I've messed with the 5 bolt s10 231C & 6 bolt 231J, I've just never laid hands on a JK case.

Looking around on the JK forums, it seems that everyone is set buying $500-700 adapters and swapping the transmission output shaft to 23 spline... which seems dumb -- And anytime a question is asked, the answer is always "Call shop xxx and throw loads of cash at it!". Plus they are all worried about speed sensor compatibility and making sure the dash lights up correctly.

I have a MP241 in a jeep wrangler ( 2013), it says 2.72 on the stamp but I believe it's been updated but can't figure out to what?