my manual shows the plug above the drawbar in the middle of the machine and just forward of the steering clutch drain plugs. this drains both the tranny and bevel gear compartments.
16 qts. of series 3 30 wt 10*F and above-----or SAE90 above 32*F or SAE80 10*F to 32*F transmission gear oil
check level with dipstick or plug on right side of tranny
does not show any filter for the transmission