I noticed while working under my Jeep that there is a threaded hole that looks like it should have a drain plug in it. It is right behind the oil drain plug on the front end of the transmission. After some digging I figured out that it is not the tranny drain plug, and now I'm at a loss. I found a size M25 drain plug that is the right diameter but the wrong threading for it, and even if I can find the right size plug I'm not sure what fluid goes in that area or how to fill it. Thoughts?
In the attached photo I believe the red arrow is the tranny drain, the blue is the oil drain, and the white is what I'm looking for.
Thanks!