4spd/Rockwell to TH350/205 swap
 

Hello everyone,

I just purchased a 67 3/4 ton long bed with a 327,4spd, & I believe a Rockwell transfer case. My question is I have a brand new TH 350 and the 205 transfer case that was going to go back into my 79 long bed. However I got rid of it a few months back.

I really want to swap out the 4spd & Rockwell for the TH350/205 set up. I assume that I will have to change the cross member and lengthen/shorten the driveling as well.

In addition A floor mount shiftier and new levers for the 205. Can anyone fill me in on what I missed or will need to accomplish this in a day/weekend.


Thanks all,

Re: 4spd/Rockwell to TH350/205 swap
 

Welcome to the board! This thread will help you a bit I hope.

Re: 4spd/Rockwell to TH350/205 swap
 

I went the other way on my swap, but to each his own.

The only thing that I see you'll need that you don't have listed is the flex-plate to bolt the torque converter to, and a vacuum line to run to the transmission. Two simple things that will bring your project to a screeching halt.

As long as you've got all of your parts( even down to the bolts and mounts), you should be able to get the whole thing done in a weekend. Maybe even a very long day.

Good Luck,

Adam

Re: 4spd/Rockwell to TH350/205 swap
 

Thanks guys,

Yeah I have the flexplate, I do need to buy a new stock converter though. I am only swapping out to a auto so it will be easier for the woman to drive. Even then if it was not for the whine in the transfer case or trans I would just have her get use to it. But from the reading the Rockwell is a b!t<h to get parts for so I figured it would be easier to swap it vs repair it.

Any tips on isolating the whine to the transfercase or tranny?

Also, I may hold off a bit till I put a small lift on it to clear the 35's I got with the truck.

Re: 4spd/Rockwell to TH350/205 swap
 

The lift would affect driveline length. I would do it once, at the same time, if you're going to do it.

Re: 4spd/Rockwell to TH350/205 swap
 

Don't forget to remove the pilot bushing from the crankshaft, otherwise the torque converter will never fit.

Re: 4spd/Rockwell to TH350/205 swap
 

The Rockwell's whine quite a lot so unless your low on gear oil, probably nothing unusual.

Re: 4spd/Rockwell to TH350/205 swap
 

i went from a 3 speed/rockwell to the 350/NP205 just recently...had to shorten the back drive shaft and lengthen the front...i had to heat and bend my shifter because it didnt want to center the hole in the floor board. and you will also have to change the radiator if yours does not have cooling line option...running new transmission lines as well....if your radiator has the cooling line options flush them because all kinds of dirt, grease and crud will end up in your new transmission....not sure if it is a weekend deal, unless you prebend your lines, and have everything handy to make the swap...miine ended up being a two weekend deal... good luck...scott

Re: 4spd/Rockwell to TH350/205 swap
 

Thanks,....I have a external Trany cooler with a fan and will be running HP rubber lines.

I will also be using a floor mounted cable shifter for the TH350, I assume your talking about bending the levers for the 205 correct? What levers did you use and what about the cross member?

I may just put the new sb 406 I have sitting in the garage in with it and know the motor & trans are both new.

Thanks,
Mike