I have a 89 Grand wagoneer with a drivers side NP231. I want to mate it to a allison 1000 in my 4bt swap.
BUT I've read that you can't mount the NP231 that I have. I would have to use a NP241 TC.. even though it's a passenger side case.
The front dana 44 is offset to the left.
Any way I could flip the TC?
I also need help finding the adapter for an allison 1000 to a NP241
NV TC's have an oiling system w/ a sump input that needs to be submerged, hard to reverse, but could check; TC's are cheap, just get exactly what you need, inputs are easily replaceable for different spline count.
I'm no expert on this but I think the allison uses a very large unique output shaft (again I may be wrong). Why not just use the stock transfer case that comes behing the allison? You can get them in manual shift no adapters or anything fancy needed.
The Allison uses the same 29 spline output as the Dodge manual and later automatics use. And you are correct, an NV261 would the the absolute simplest case to put on, since it came behind the Allisons. Just make sure it hasn't suffered from pump rub, and put in the kit to prevent it from happening.
The best reason one might want to use a 241 rather than a 261 is that slip yoke eliminator kits are available for them. In that case, you would have to use a Chevy 241, because the SYE mainshaft won't be compatible with a Dodge 241DHD. I think you can put the Dodge input in the later Chevy case, but not 100% on that one...
91 K5 Blazer, P-pumped 12V, NV4500, 205, D61, 14BFF, 4.10's and rolling on 35's