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Which Oil Should I Use?

Your outboard motor was not a small investment, and we know how much performance and life-span matter to you. Keeping your engine well-maintained will help you get the most out of your craft, so you can enjoy your adventures out on the water for as long as you can. 

Today’s engines are intricately tuned to run as efficiently as possible within very strict tolerances. The engineers at the manufacturer formulate oil specifically to maximize the efficiency and performance of their engines. That’s why we sell only oils formulated by the original equipment manufacturer at Domo-Online. Remember that requirements for two-stroke and four-stroke engines are very specific; look for your brand below or call us for additional information.

Evinrude Johnson

The Evinrude E-Tec is the most efficient, cleanest burning outboard Evinrude has ever made. These engines are formulated to run on XD100 oil. An E-Tec can also be programmed to run on XD50. When programmed in this manner, however, oil consumption will go up considerably. Often, owners find that the additional cost of the XD100 oil is offset by the reduction in oil consumption.

  • If your E-Tec is programmed to use XD100, DO NOT USE XD50!
  • XD50 is formulated as a TC-W3 certified oil, and is certified for direct injection engines.
  • XD30 is also a TC-W3 certified oil. It is approved for all pre-mix applications.

Mercury Optimax

Mercury Optimax Outboards are also designed for performance and efficiency and require special oil formulated for direct fuel injected engines. Mercury engineers recommend this synthetic blend to help the engine run cleaner and more efficiently without the carbon buildup associated with most 2-cycle oils. Prior to the development of this oil, it was recommended that Premium Plus be run in Optimax outboards, but that has since changed to the superior Optimax Oil.

Premium Plus is also formulated for direct fuel injected engines. It also meets or exceeds all outboard and personal watercraft manufacturers’ recommendations for the use of TC-W2 and TC-W3 in pre-mix or direct injection 2-cycle applications.


Yamaha has one of the most diverse lines of 2-stroke products available. However, their designations are easy to understand. If you have a Yamaha 2-stroke outboard, use 2M. If you have a Yamaha 2-stroke personal watercraft, use 2W. Using the right marine oil for your craft will ensure that you’ll continue to have a smooth-running engine and great times out on the water.