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and try out the diesel oil /rotella 15w-40/ first.not like that is gonna give me more power but might help the engine.


huh? I don't think 15w-40 (diesel or not), is necessarily a great idea. IIRC, you won't find this as a recommendation in your owner's manual. most around here prefer the 5w-30 or even the new 0w-30 weights to reduce the classic isuzu lifter chatter. I would stay away from 40w oil though, just too thick and not what these import motors are designed for.

-Rob