Anyone know what this could be? It's where the engine meets the transmission on the passenger side.

 

Ant time I see oil residue like that, I clean it up with brake clean, and keep an eye on it to see where it starts again. Once in a while, I'll get lucky and it won't reappear, which saves lots of troubleshooting time.

Oil can migrate from an area unrelated to where it collects and drips off.

 

Excellent tip thanks

 

There are two separate pieces to the oil pan one is the oil pan and the other is for the lack of a better term upper pan. The upper pan gasket leaks for some reason and not sure why. I had the same issue and thought it was the rear main seal but when I had my transmission out for the clutch change the rear main seal was fine. I had mine covered under warranty.

R/
Will