Extreme Duty Marine Semi Synthetic 20W-50 Engine Oil

Extreme Duty Marine Engine Oil Semi Synthetic SAE 20W-50

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 severe 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


  • #10654 - 1 Quart (Case of 6) - 13 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
zinc Zinc Values

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Woody Cofield uses Lucas Heavy Duty Oil Stabilizer for 1986 Jeep Pick-Up

I wrote ya'll not long ago and told ya how impressed I was with the Lucas Oil Treatment.

Well, my 1986 Jeep Pick-up 2.8 V6 4X4 started making grinding noises from underneath in the transfer case.

I remembered how well Lucas worked on improving my mileage and how it can be used in the trans,& transfer case & differentials, so I added it to all. The transfer case was down a full quart and the rest took another quart.

I was thinking of selling my Jeep, but now it runs so smooth and no more noise.

Thankx for a truly remarkable product.


Woody Cofield

Lebanon, MO

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