I have a hitachi 2nd fix gas nailer and im ...

Depending on how much you use the tool. Only apply oil to tool after you have given tool a strip and clean. Or for General maintence just 4 - 6 drops of oil every 3 - 4 week only if you use tool more then 3 times a week( 10,000 nails).Only on the fan assy O-rings.Remember this is only a guide.But if you need more info then try the hitachi web sit or your nearest nail gun repair agent.Good Luck