Sealing Surfaces

6.0L PSD engines were known for bed plate oil leaks which can be caused by improper disassembly and assembly of the front and rear covers that can stretch the lower spaghetti gaskets. But what you are looking at is the sealing surface of the cylinder block that mates with the lower bed plate. The casting and or machining here is absolutely horrendous and with a surface like this the thin rubber seal simply cannot effectively seal. Ford has endorsed the use of anaerobic sealant to fix this condition.