Swap 4x4 46RH tailhousing to a 46RE?

My end goal is to have an OD transmission (RH or RE), that will mate with a transfer case with a passenger side drop.

I recently got a 5.9l/46RE from a 99 Durango to swap into my 72 w200. That drivetrain had a 241 (I think) tcase with a driver side drop to the front axle. I have a married NP205 from a 1st gen ram cummins that has a passenger side drop.

Problem is, the tailhousing on the 46RE from the durango has the output shaft sticking about half an inch past the mating flange. The output shaft and the input shaft on the 205 then overlap each other by about half an inch.

I also have a 46RH from an early 90s jeep, and the tailhousing is both longer (due to the RH governor), and most importantly, the output shaft is about half an inch inside the mating flange, so it should mate with the cummins np205 just fine.

Does anyone know if it's possible to swap the tailhousing and OD set from the RH to the RE? I did find this about going the other way:


It looks like there's line pressure going back to the governor, and governor pressure coming back to the valve body through the two tubes. I presume the RE doesn't have anything to connect to these tubes, so is it as easy as leaving the tubes and governor assembly out?

You probably already know this, but the 46RE is computer controlled. Don't know about the tailshaft swap though.

Check around for a "clocking ring" 4wd guys use these to rotate the front output of a transfer case down for driveshaft angle.

Is it possible to chop the output shaft on the RE? Got to imagine it would be like shortening an axle.

Yep. My plan is to use the stock ECU for the trans and engine. If I have to, I can dust off the prototype RE controller I built and get it going again.


Oh, good idea. I may need to do that anyways


I've considered it. I don't see why it wouldn't work, other than changing the part so any repair in the future needs the same thing done.


Thinking more about it, and watching numerous rebuild videos, if I take apart the RE and there are no provisions to send fluid back to the governor, I think it will work to just remove the entire governor assembly in the tailhousing.

I am relatively sure you could bolt on the RH unit to the RE without much ado. Since you won't be using the governor anyway it will be just along for the ride. You can remove the outer governor feed hub with tubes from the O/D case so they aren't in the way. The output speed sensor may be a problem though depending on the configuration as I believe they changed over the years. I can't recall how the RE was set up.

Great. That's exactly what I needed to know. Thanks!

I just wasn't sure if there was something obvious that was going to be in the way or not.

This np205 has the cable driven output, and there's a passthrough electronic adapter to generate the VSS signal available, but, I still need to figure out if that's different than the one on the tailhousing.

Here's a picture of the RE, and the transfer case. The inspection cover to release the OD drum set is the same distance from the main case in both the RE and RH, so those bearings should be interchangeable.

And here's the RH housing. Instead of ~8" long like the RE, it's closer to 14".

That extra length is for the governor. As long as you can work out the VSS you should be golden.