How do I completely get all the transmission fluid out of the drain hole on the bottom of the transmission pan?

Hi,

You won't get all of it out by draining it or even removing the pan and filter. No matter what, there will be fluid that remains in the valve body, the torque converter, and the front pump. The transmission cooler and cooler lines will also hold fluid.

If you want all the fluid out, you need to power flush the transmission. In most cases, which requires a special tool that allows the old fluid to exit through the cooler supply hose and new fluid to enter the trans system via the return hose.

Let me know what I can do to help.

Joe