The 85w-140 SuperTech gear lube is GL-5 rated but the back of the bottle also says "prevents corrosion on brass and bronze." I'm beginning to wonder if it's really going to even matter! Can someone verify that the circled plug on the attached picture is where I would fill this 1936 4 speed transmission? I'm sure the drain plug is the lowest one and am assuming the circled plug is where I would fill and probably fill just until it gets level with that hole? Thanks for the help!
