2009 7 speed trans fluid change
 

Looking at draining and refilling the 7 speed trans fluid. Draining it appears to be pretty simple, drain plug, but was curious if it could be refilled by adding fluid via the trans fluid return cooler line. Refilling with exactly what comes out so it won't be under or over filled. Not looking to pump it back in via the overflow port as stated in the service manual. Thoughts

Look in the drivetrain forum and the D.I.Y. Forum for tutorials.

Do the procedure in the service manual. It's not that difficult. There are instructions for building a cheap pump that will turn it into a 1hr job. Otherwise you're going to be making much more work for yourself