Full Size Jeep Network

Hello, I was wondering if anyone can point me in a direction to go with my jeep I have purchased an NV 4500 with a 23 output spline out of a Dodge ram my transfer case is a 31 spline it will not fit what transfer case should I be looking for to get this accomplished. My Jeep is a 1980 j20. I also noticed upon putting the transmission side-by-side the NV 4500 appears to be about 6 inches shorter than the T 18 what have any of the other Jeep swaps done to make this set up work? Any information would be greatly appreciated I’m hoping to drive my truck again this year thank you.

The T18 has a spacer on the front so that the shifter doesn't end up under the dash. The 80+ T18/NP208 is actually a very rare setup. And that version of the NP208 won't work behind many other transmissions. Its best to keep that T18/NP208 setup together. If you are going to sell them to another FSJ owner, they would need them together as the trans isn't of much use without the t-case.

However, finding a 23 spline input driver drop NP t-case should not be hard. Although as I recall there was two versions of the 23 spline input.

As for the swap itself, plenty of people has swapped in NV4500s. You will need to bend the shifter to clear the dash. But another question is, which NV4500 do you have? The gas V8 version or the V10/Diesel version? If you have the diesel version, I think you need to swap out the input shaft to work behind a gas V8. And you will need a bell housing adapter, and a bellhousing.

The T150 bell housing is what you will need, and then an adapter like this: https://www.northwestfab.com/AMC-V8-Eng ... _3784.html

Most adapters are for GM versions of the NV4500, the one linked above is specific for a dodge V8 version.

I did get the gas v8 version. Actually the shifter looks as though it will be in relatively the same spot as the 18. I am keeping the t18 bell housing and have the spacer from AA. I just need to know what guys have done for the driveshafts. I’m assuming they had new ones made.

Smkozma69 wrote: ↑Sun Apr 25, 2021 6:51 pm I did get the gas v8 version. Actually the shifter looks as though it will be in relatively the same spot as the 18. I am keeping the t18 bell housing and have the spacer from AA. I just need to know what guys have done for the driveshafts. I’m assuming they had new ones made.

You will need to shorten the front shaft, and lengthen the rear shaft. But you won't know exact measurements until its all installed and you can measure from yoke to yoke.

After actually doing the swap here is the information I can pass on to anyone interested.
I used a gas dodge nv4500
Ordered a spacer from AA (all factory clutch works fine)
Used a np241 DLD 23 spline from 95 dodge
Also used the np 241 shift arm from dodge
The transmission sits in almost the exact same spot as the t-18 so no issues with sifter.
Used the dodge trans mount
Had to rework the trans support it stayed in the factory position
The front driveshaft from the dodge fits perfectly
Used the rear driveshaft out of the dodge
It had to be shortened
Hope this will help someone interested.

Hi Smkozma, I was wondering on your input shaft for the nv4500. If you say you are using the same shifter hole as the t-18, what input shaft are you using that is it as long at the t-18? I thought the nv4500 had only one length input shaft around 7.5" or so.

whitejeepguy wrote: ↑Fri Jan 14, 2022 7:03 am Hi Smkozma, I was wondering on your input shaft for the nv4500. If you say you are using the same shifter hole as the t-18, what input shaft are you using that is it as long at the t-18? I thought the nv4500 had only one length input shaft around 7.5" or so.

The NV4500 being a 5sp is a longer transmission and the shifter is more towards the rear of the top cover. So I think that's why it ended up in an ok location.

Smkozma69 wrote: ↑Sun Jan 02, 2022 7:41 am After actually doing the swap here is the information I can pass on to anyone interested.

Thanks for posting up the info. I am sure it will help others in the future.

Stuka is correct the nv4500 doesn’t need the 4” (or so) spacer that my t-18 used. With the spacer from AA and the factory amc bell housing the input shafts were pretty much the same length when measured side by side. The T-18 itself is a short transmisson with a long input to get the shifter in the correct spot.