i just completely changed my atf to redline d4 this weekend (not drain and fill). here's the easy procedure:

1. drain and fill atf as normal. about 4 quarts.
2. remove oil cooler lines from radiator. you can either remove passenger side that connects to raditaor or drivers side that returns to sump. IMPORTANT, oil runs passenger side >>> driver side through radiator oil cooler. If you choose wrong direction oil will spill all over.
3. direct hose to empty pan and have someone start your engine.
4. drain 3 quarts at a time (about 3-5 seconds of engine running).
fill 3 quarts through dipstick.
5. repeat step #5 once and drain another 3 quarts.
6. your done! that's 10 quarts new atf and 10 quarts old atf removed.

The shop charges vary for atf flush ($75-150). this way you can put in the atf of your choice.

 

That does sound like a good idea. But how do we know for sure it gets the torque converter?

 

the atf is always running through the entire system, all we're doing is catching it before it returns to the sump then replacing through the dipstick.