You can completely flush your tranny and converter by first drain/remove pan and change your filter and put the pan back and fill with the fluid you want and remove the return tranny line and put a bucket under it and start your engine and let it pump out the fluid into the bucket until you see the clean fluid (you can tell when the clean fluid comes out) if it starts to run out of fluid shut motor off and fill back up.It is best to have someone help so one can start the motor and one can watch the bucket.This totaly gets the old fluid out of the converter.