The oil discussion I'll leave to someone else, at least the details. However I have noticed that most here use synthetic 5w-40 diesel oil (like Rotella T) and seem happy with it.

However, they are indeed hydraulic lifters that do not need manual adjustment.

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1979 300D 040 Black on Black - 1985 300D Maaco job (sadly sprayed over 199 Black Pearl Metallic) on Palamino

http://i.imgur.com/LslW733.jpg

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