You'd need an adapter and I'm not sure of any out there. Is it a GM, Ford, Dodge etc version. They came with different bolt patterns as well as inputs. If you did find a way to mount it up your low range would go from 2.72 to 1 to 2.62 to 1 and it weighs a ton so you'd need some sort of support and of course new drive shafts and shifters.

A tcase swap isn't hard anyways.
Both are nearly the same strength wise

I hope you're referring to the 231 and 242 and not the 205. The 231 is a little stronger than the 242 but the 205 is a gear driven cast iron cased box vs a chain driven aluminum case. Big difference in strength.

I was talking about the 231 and 242

my 242 is trashed. I want to go to pick and pull to find a new 242 but theres plenty more 231's. so my question is the opposite, what will I need to go from the 242 to the 231?

I guess linkage and maybe the speedo plugin on the tcase.
May or may not be different

yeah I have an 88 so the speedo is cable driven,
ill try to grab a 242 but if I can only find a 231 ill research some more
thanks man

It would be from a 79 ford

OP, where are you located? I'll gladly swap you my NP242, lol. I really like the full-time feature, but I want more SYE choices

The speedo will swap from cable to wire you just have to swap the entire assembly, gear included. I've swapped 249s with 242s and 231s as well as 242 with 231s and used the same shifter each time. Never bothered to swap it just adjust the rods underneath and it's fine.

Neither Advance Adapters or Novak make an adapter to use the 31 spline 205 on the 21 or 23 spline AW4. Someone may make one but I wasn't able to find anything. While the case is stronger it's stock low range is not as low. It can be twin sticked but isn't cheap unless you just want 2lo and not front only. This can also be done to the 231 for about the same price.

Just don't drive 55 when there is snow.

I don't think you understand what I'm sayin but regardless if I wanted to drive like I'm in a 2wd honda I wouldn't be driving a jeep

I have a 242 I would trade for a 231out of a 97 or later.

and whats wrong with the 4wd hi range in the snow you have now?

I have used mine with my old 231 with no problems, the dana 18 in my dads ****** with no problems, my second xj with no problems and my dads f350 on 37s with no problems...


if youre talking t case swaps to other cases and are considering the 205, check out going to a dana 300. the flip adapter isnt too much from northwest fab and is stupid easy to install as long as you know how to tighten up a few bolts