drag_banshee

thanks for the help guys. But the o-ring doesnt look bad at all.....?

hello everyone im new here and i have a question. Went out to ride my banshee the other day and noticed a trail of tranny fluid following me into the garage. It seems to be coming from behind an odd shaped plastic cover of some sort on the left side housing that has 3 screws in it. There is a o-ring on the back side of this piece. Any help to what this piece is or how to fix it would be very helpful thanks.