231>249 Swap?

[Comanche_Fanatic]

I have an '88 Pioneer 4.0 4x4 BA10/5 D35

 

I just got an '96 AX15(external) yesterday, along with clutch/flywheel/salve cylinder/etc, it has 23 splines output shaft. it came off an '96 XJ 4x4 4.0L. I know i will be getting a few more parts for the transmission swap.

 

my current tcase is the 231 with the BA10 is a 21 spline, so I'm looking for a replacement tcase. I'm a fan of the 249 so I'm researching as much as I can about this, its hard so far cause most go the other direction. I am not 100% sure it will bolt onto the AX15 perfectly, and if I have to swap out/shorten driveshafts. if i have to lengthen the rear driveshaft by 1" i will look into a D45 rear to compensate for that. and will some disassembly be required between the 231/249 to fit right? Yes I am aware I will have to replace the front axle as well to eliminate the vacuum system. I am gathering as much info so I can order parts in advance and reserve a few days for this swap project.

 

all i want is a confirmation that the 249 will bolt onto the AX15(23spline/external), if so, what year 249 is required for a '96 AX15? as far as I've read is that some ZJ models swapping from 249 to 231, and doesnt require changing out driveshafts. some dis-assembly is done tho. and some people have mentioned that the year of the tcase makes a world of difference.

 

 

any info would be very helpful, please stay on topic as well.

 

thanks in advance!

[Mattwheels]

You could keep the 231 easily by switching the input gear on the 231 with the input gear of the 249, I'm actually doing this myself picking up a used 249 for the input gear alone. and you can eliminate the vacuum system right now by bypassing it. Cruiser Just gave me this link not more than a couple hours ago.

 

http://www.cherokeeforum.com/f51/free-d30-cad-bypass-91-a-38629/

 

do this retain the D30 save some money and make life easy

 

Also all 249's are 23 spline so even a cracked 249 you pick up cheap would work. although, You might need to find a 249 from 94+

 

This is a great website for information

 

http://www.novak-adapt.com/knowledge/np_nvg_input_gears.htm

[mvusse]

The reason most people go the other direction is because the 249 uses a viscous coupling that WILL eventually go bad. Fact of life, no viscous coupling will live forever. This part is $1300 from the dealership, or $500 from Quadratec.

 

A 231 transfer case can be had for $100 or less. (I picked one up for a buddy a couple of months back for $50)

 

If you want AWD capability, a 242 can be had for the same. (I paid $50 for one with a hack-n-tap SYE started but not finished)

[Comanche_Fanatic]

You could keep the 231 easily by switching the input gear on the 231 with the input gear of the 249, I'm actually doing this myself picking up a used 249 for the input gear alone. and you can eliminate the vacuum system right now by bypassing it. Cruiser Just gave me this link not more than a couple hours ago.

 

http://www.cherokeeforum.com/f51/free-d30-cad-bypass-91-a-38629/

 

do this retain the D30 save some money and make life easy

 

Also all 249's are 23 spline so even a cracked 249 you pick up cheap would work. although, You might need to find a 249 from 94+

 

This is a great website for information

 

http://www.novak-adapt.com/knowledge/np_nvg_input_gears.htm

 

you rock dude, so I will need a 249 short input to pair with the ax15, and a bypass to top it off.

 

The reason most people go the other direction is because the 249 uses a viscous coupling that WILL eventually go bad. Fact of life, no viscous coupling will live forever. This part is $1300 from the dealership, or $500 from Quadratec.

 

A 231 transfer case can be had for $100 or less. (I picked one up for a buddy a couple of months back for $50)

 

If you want AWD capability, a 242 can be had for the same. (I paid $50 for one with a hack-n-tap SYE started but not finished)

 

yes i am aware of the VC that will go bad, I don't drive my Jeep that much and will be relocating within 3 miles of my job. I had considered the 242 but the 4-full time isnt the same as the 249 since theres no limited slip and less power to the front from park.

[JeepcoMJ]

Actually, there is equal power from front to rear with both cases, and it is evenly displaced except when a wheel slips. A 242 basically has a differential with planetary assembly inside. It is stronger, more reliable, less prone to failure.