I started to get an oil leak at the very bottom of the area where the Engine bolts up to the automatic transmission. It appears that the aluminum casting along with a partial rusting of the plate that covers the difference in housings has corroded. Can I just RTV that hole? Does that area between the engine and auto transmission sometimes hold engine oil that has seeped from the motor into that open space. Due to the corrosion, it now drips oil from that area. Fixes, remedies are appreciated.