I was wondering if anyone here has swapped a married 205/435 combo into a highboy?
I currently have a NP435 with a divorced NP205 case but I keep breaking yokes on the intermediate shaft when I get the truck in a bind and get throttle happy...
I bought a married 435/205 combo that I am planning on installing. It looks like a win win situation because I am running a high pinion D60 from a 78 F350 and that d-shaft angle will look better with the case farther forward as well the rear drive shaft angle will improve greatly

So what am I missing here?? Has anyone done this??

Thanks
John

 

Me personally know, the only thing that i could think of though, would be shift linkadges...

 

and drive shafts.....

 

Im not sure what you mean by Drive shaft angles looking better?as it stands now,you've got nearly identical length front and rear driveshafts,so if you run a married combo,your going to get a much shorter front shaft and a longer rear.I would assume that Ford could have found a way to make the Highboys with married combos vs the div. mounted that they chose,and would therefore also assume that there engineers saw an advantage to that design. Besides,if your breaking stuff now,why do you assume that you wont break other stuff after a change? The fact that Ford dropped the Highboy version of the F250 when they adopted the married trans/t case has me questioning whether the higher stance worked well with the marriage,or were other problems encountered? I seem to recall seeing some Np205 cases utilized in Div. mounted applications that were equipped with some sort of strut rod or support,is there a chance that your heavy throttle foot is causing your case to move,and if so could that movement be causing the yoke to break?

 

When I installed a doubler (203/205) combo, I went with a married unit.
Since I was changing linkages, to cable operated shifters, the linkage was no longer an issue, and There were no problems with the install.
However, I do not see any reasons why you divorced case is having such a problem.
There was a time when mine broke an ontermediate shaft, and it was because the shafts splines were dry (had some mud in there) and the slip joint was in a bind.
Popped a yoke, but after the shaft was replaced, has been working well.
The intermmediate shaft really does not have a whole bunch of stress on it. When the case is engaged into 4 lo, it has even less. Gear reduction in the case gives the intermediate shaft a nechanical advantage over the other shafts. Axles should be breaking before the intermmediate shaft.
As mentioned above, it sounds as though you have a problem in the intermmediate shaft itself.
In some cases, I have seen the divorced case actually moved foward to lengthen the rear shaft. this shortens the front shaft, and in some cases permits the use of equal length d-shafts. Cool to only have to carry one spare shaft on the trail.
It is also common to see the case re-indexed to raise the front output, for clearance purposes. Lots of room under the cab for this, but linkages have to be re-routed, and the mid crossmember has to be modified to clear the front d-shaft, but the case can be raised way up out of the way.
I suppose you could install a married unit, but that front shaft does start to get a little steep, if you have a fair amount of lift. I still think that you have a problem that can be fixed without replacing the case.