According to page 6 of the Dewalt Nailer DWMIIIFN user manual, which is available on line, “''Lubrication -'' Frequent, but not excessive, lubrication is required for best performance. Use Air Tool Lubricant, Mobil Velocite #10, or equivalent. Do not use detergent oil or additives as these lubricants will cause accelerated wear to the seals and bumpers in the tool, resulting in poor tool performance and frequent tool maintenance. Only a few drops of oil at a time is necessary. Too much oil will only collect inside the tool and will be noticeable in the exhaust cycle.
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