I thought that you would be interested to see the BG trans flush machine that we have at the shop where I work,
Inside the cabinet there is a large drum which is seperated into 2 halves by a rubber diaphragm, one side for the new trans fluid and the other side for the used fluid. The machine is filled with 15qts of new fluid and the lines are hooked up to the tranny cooler lines.
Then as the engine is idling, the dirty oil leaving the trans is replaced by clean oil entering, you can see the old oil in the sight glass.
After it has completed the flush, the new oil guage flips low and the used oil guage reads high, next you switch off the motor and remove the lines.
The transfusion is complete.
