itlksez
Member
- Joined
- Oct 6, 2009
- Location
- Post Falls, ID
Hi everybody.
I just completed an adapter that joins an M45 transmission to a Dana 300 transfer case. I thought I'd post it up here for reference. (In case you're wondering, I'm dropping a B230 - plus a turbo if I can get it to fit - into a '49 Willys CJ3A.)
The hard part of this swap is figuring out how to join the M45 output shaft to the 23-spline input of the D300. I picked up a core 46RE automatic transmission on CL for $20 that came from a 4wd Dakota. I knew this trans came bolted to an NP231, which has the same 23 spline connecting shaft as what I needed. My original plan was to take the risk of cutting the output shaft and making a "double-D" slot and welding the backside of the connection to the driveshaft yoke of the 240 that this trans came out of. I still did it, but now that will be a spare. (Yeah, that's a wood lathe. Don't judge.)
What I wasn't planning, was that the shaft that goes through the planetary gearset for the 46RE's overdrive was the same 23 spline shaft. I was able to take the gearset...
And cut/turn it down to a plate that accepts a section of that shaft. The shaft can float but can't move forward or back. I also turned a lip in the back so it locks into the M45 tail yoke...
And that slips into the D300 input.
Now it's just a matter of making plates for the trans and t-case, and connecting them. I took the rear housing from the M45...
And made a 1/4" plate that fits over it...
I then did the same thing with the Dana 300 transfer case.
With the plates on and the cases in place, I measured the distance between them and cut a section of 5" pipe. I centered that on the t-case plate and tacked it.
I cut out a section of the pipe to accept the shifter rod and also needed to cut out and cover a section on the bottom to allow for a gusset in the tail plate. I stood the M45 on-end and placed the adapter on the trans plate. I took the bull-gear assembly out of the D300 and used that to center the unit and tacked it in place.
Then I welded everything up!
A peek inside...
It worked great, but I still needed to figure out the shifter.
I cut the shifter rod (from an M46) down as short as possible and made a plate to bolt to the transfer case to mount the shifter assembly to. It took a bit of trial and error, but I got it.
And here it is, all finished!
I just completed an adapter that joins an M45 transmission to a Dana 300 transfer case. I thought I'd post it up here for reference. (In case you're wondering, I'm dropping a B230 - plus a turbo if I can get it to fit - into a '49 Willys CJ3A.)
The hard part of this swap is figuring out how to join the M45 output shaft to the 23-spline input of the D300. I picked up a core 46RE automatic transmission on CL for $20 that came from a 4wd Dakota. I knew this trans came bolted to an NP231, which has the same 23 spline connecting shaft as what I needed. My original plan was to take the risk of cutting the output shaft and making a "double-D" slot and welding the backside of the connection to the driveshaft yoke of the 240 that this trans came out of. I still did it, but now that will be a spare. (Yeah, that's a wood lathe. Don't judge.)
What I wasn't planning, was that the shaft that goes through the planetary gearset for the 46RE's overdrive was the same 23 spline shaft. I was able to take the gearset...
And cut/turn it down to a plate that accepts a section of that shaft. The shaft can float but can't move forward or back. I also turned a lip in the back so it locks into the M45 tail yoke...
And that slips into the D300 input.
Now it's just a matter of making plates for the trans and t-case, and connecting them. I took the rear housing from the M45...
And made a 1/4" plate that fits over it...
I then did the same thing with the Dana 300 transfer case.
With the plates on and the cases in place, I measured the distance between them and cut a section of 5" pipe. I centered that on the t-case plate and tacked it.
I cut out a section of the pipe to accept the shifter rod and also needed to cut out and cover a section on the bottom to allow for a gusset in the tail plate. I stood the M45 on-end and placed the adapter on the trans plate. I took the bull-gear assembly out of the D300 and used that to center the unit and tacked it in place.
Then I welded everything up!
A peek inside...
It worked great, but I still needed to figure out the shifter.
I cut the shifter rod (from an M46) down as short as possible and made a plate to bolt to the transfer case to mount the shifter assembly to. It took a bit of trial and error, but I got it.
And here it is, all finished!