I have a 2000 ZF6-S650 transmission that is going into a F350 project. I am wondering if it is possible, or worth it, to do the upgrades to the S650 to make it into the later S750 version. I know the input shaft is larger but what other internal components are different? Any assistance would be greatly appreciated!

THANKS!

 

Talk to Dan at Midwest transmission. I had him build one for my 550 hauler. you're correct that the input shaft is bigger and 1/2 syncro is improved, along with 5/6 gears are heavier. the flywheel will need to be machined to accept the larger pilot bearing.
https://www.midwesttrans.com/

Barney

 

Any other suggestions or thoughts on what some of the weak points are on the ZF6 650 version? I know it is a pretty stout trans and should hold up fine but if I am going to go in there once, I figured I would make it right the first time!