Originally Posted by M3PO
Thanks for this! I am planning to do this soon.
Just an FYI for people, there's a large portion of the old tranny fluid in the lines, pump, and cooler. To truly change it all, the pump has to be activated. From what I understand, the method in this DIY only drains something like half of the fluid in the system.
That is right. Nice catch.
I still haven't figured out a way to drain the transmission cooler. I read that you can send power to one of the plugs which will turn the motor on allowing the rest of the oil to pump out. I also heard BMW techs can turn it on via DIS Tester. If I find a way to do it I will update.