Extreme Duty Marine Semi Synthetic 20W-50 Engine Oil

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Extreme Duty Marine Semi Synthetic 20W-50 Engine Oil

Lucas Extreme Duty Marine Semi Synthetic 20W-50 Engine Oil is designed for use in high performance boats requiring the ultimate protection.

Lucas Extreme Duty Marine Semi Synthetic 20W-50 Engine Oil is manufactured with the highest quality paraffinic base oils and is fortified with an exclusive additive package containing high levels of Zinc, Moly and Phosphorus that provides a tougher, thicker additive film for maximum protection even under the most sever conditions. It lowers oil temperatures, extends oil life and minimizes metal fatigue.

Lucas Marine Semi Synthetic 20W-50 improves the film strength between the cylinder  wall and piston rings and slows oil burning while improving pressure levels in worn engines. It has good cold temperature properties and stands up to high operating temperatures. This product is compatible with methanol and all racing fuels.

Key Benefits

  • Excellent for use with supercharged, turbo charged or nitrous oxide high performance engines.
  • Protects against rust and moisture during long periods of storage.
  • Safely blends and is compatible with synthetic and non-synthetic oils.
  • Dropping point 540 lbs
  • Provides rust and corrosion protection in both fresh water and salt water environments.
  • Effective Water Resistance
  • Long Lasting
  • Resist Extreme Pressure
  • Extreme Friction Reducer

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* Size:


  • #10654 - 1 Quart (Case of 6) - 12 lbs
  • #10811 - 5 Quart (Case of 3) - 31 lbs
  • #10667 - 5 Gallon Pail (1 Pail) - 40 lbs
  • #10668 - 55 Gallon Drum (1 Drum) - 440 lbs


Product Spec Sheet Technical Data Sheet
Safety Data Sheet Safety Data Sheet

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Chris Wywiorski uses Lucas Fuel Treatment for 1999 Dodge Dakota

Dear Dale,

I began using Lucas Upper Cylinder Lubricant and Injector Cleaner (fuel treatment) a few years ago. It was my introduction to the Lucas family of products. I have since become aware of the benefits of other Lucas products and have been implementing them into my personal vehicles as well as my company trucks and vans.

I know that mondern day fuel and ignition systems have come a long way in extending engine and parts life but I have never seen anything like what I'm about to tell you.

The enclosed (8) spark plugs came out of my '99 Dodge Dakota which I drive every day. I bought the truck new and and developed a misfire at around 20,000 miles. I replaced the spark plugs and the misfire stopped. So far, no big deal.

The truck has now had 116,000 miles which means these plugs have gone 96,000 miles and look almost like new. The only thing I can attribute this to is the continued use of Lucas Fuel Treatment.

The truck averages 15 MPG and has never fallen off in all this time. If I had not already purchased new plugs I would have been tempted to screw these right back in but I thought you and Forrest would get a kick out of seeing and hearing this.

I have and will continue to be an ambassador for your product. With results like this I'm confident Lucas Oil Products will continue to prosper. In my business, I'm quality driven. It's great to know you folks are also.


Chris Wywoirski
Audio Images Stereo, Inc.

Whitehall, PA

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