The 722 box first came out in 1996, it was intended to be a sealed for life unit. Some torque converters had drain plugs fitted up to the 09.99, but by this date no cars had them.
Owing to the problems encountered with the boxes over the fluid and great pressure from the forums the sealed for life has now been scrapped and the recommended distance is now 40k miles. It is only of late that most dealers have accepted this.
The no drain plug gave further issues as only ½ the fluid can be drained by conventional means. Some good indies worked out a way to drain the complete box so that the full 7 liters plus can be changed.
once again that a great help , so mine really needs changeing round about now but does that mean that i have no drain plug on the torque converter ? if this is the case i will have to finf a way of draining the rest of the fluid eg a cooler pipe from somewhere