DaveBen
SDD Senior Member
Yes it was the fill level plug. Most people remove the cover to drain the gear oil, I do. Your choice. I do not know anybody who has done that. Maybe someone will chime in.
Not the cover,the BOTTOM of the cast houseing.There is a round,flat spot where they used to put a drain plug.I guess it was to expensive to dril/tap a hole!They quit doing that in the late 80's.I have seen covers that have what you are talking about,but it was higher up and was at "fill level'.