Repairing old equipment: Case 680CK, Part 1 - Differential disassembly 

Thanks!!

On mine, the transmission is part of the rear end, at least where you shift it into first thru 4th gear. The torque converter as its called is bolted to the back of the engine. I am pretty sure you can take this out without taking out the engine. On mine, the torque converter unit is joined to the transmission with a small drive shaft. If you have the serial number, you can go to the case construction parts website and you can find the parts manual for the machine free to view there and you can look at specifics of the torque converter to see how it mounts.

Hi, in the transmission/rear end assembly I use just common 80w90 gear oil. In the shuttle trans I am running Chevron 1000 THF.

@@bigmikesmotorpool9263 merci beaucoup thank you very much