I don’t care how hard it will be or what it will take. I’m looking to adapt a ZF6 (stronger S6-750 version) to my 300 I6 in my 1980 F250. I know this truck is like three generations away from the ZF6 trucks but I’m sure it’s do-able. Just wondering if anyone has put one of these in a F250 Bullnose I’m certain it’s been done. This wasn’t exactly in the how-to so I’m making this post. Any and all help is greatly appreciated, thanks in advance!

 

I dont think anyone has posted if it has been done
Just off the top of my head what you will have to deal with.
You will need to swap over to hydrolic clutch, not hard as the later bull nose used them.

The later 5sp and guessing the 6sp is no speedo cable hook up as they run off the rear end.

Now the big one is the transmission bell housing to motor bolt pattern.
The 300 six is a small block pattern what is the 6sp that you are going to use as I dont know the newer stuff?
If it is also a small block pattern then it is down hill from there I think.
If not then you will need to find an adapter to work.

Keep us posted
Dave ----

 

If you had a diesel truck this might be possible, but the belhousing is integrated on all the newer transmissions and the 300I6 was discontinued before the ZF6 existed so there are no versions with that bolt pattern.

 

That is what I thought so either need an adapter or it cant be done.
Dave ----

 

I know it’s brutal lol but there’s gotta be a way. Machine a plate that has the 7.3 power stroke AND 4.9 Straight six holes is my guess

 

Thing is is the trans input shaft long enough for adapter?
Dave ----

 

oh the shafts are probably all different sizes lmao. Will certainly be a challenge

 

If the end of the input shaft is not long enough to reach the pilot bushing / bearing to support it the trans will be junk in short order.
Dave ----

 

can’t just get a longer shaft? Will probably have to be custom made anyway due to different diameter and spline count

 

I would think with a little looking you could find a disc that would work but the shaft would be custom and bucks.
At that point unless you can make it yourself it would not pay to use that transmission in my book.
Dave ----

 

I see. I believe the 6.0 powerstroke clutch may work but hard to know. Will have to find a wrecked one and do some measuring or find specs online. There’s a shop in town that does custom shafts I can’t imagine it would be too much. Will also have to use 6.0 t case so it goes with the transmission, would be a pain with the NP208. I think my best bet is to make a 6.0 PS to old SBF adapter plate and then figure out shafts and all that.

 

I know you don't need any naysayers in this thread, but have you studied what you will gain? Both ends of the ratios on a 6 speed are close to the 5 speed zf, all you are gaining for all this is a extra gear in the middle. But keep on keeping on.

And it seems you already know Ford broke their previous pattern and only the later transfer case will bolt to the 6 speed. That would be the easiest way around that.