Swepco 306 20W-50 multi-grade oil is our motor oil of choice for the Porsche 356 engine. Zinc and Phosphorous are important anti-wear additives that have been drastically reduced by many of the newer SM oil formulations. These additives are crucial to the air cooled Porsche and are beneficial to any car, water or air cooled. Swepco 306 has high levels of Zinc and Phosphorus as well as including over 5 times the amount of the anti-wear additive Boron when compared to the newly reformulated SM or CJ-4 oils.
Benefits of Swepco 306 include: Superior friction reduction, cooler operating temperatures, reduced friction and drag, improved fuel economy and lower octane fuel required. It Exceeds most engine manufacturers specifications and recommendations, so it's the one oil for most applications. Being a multi-grade weight oil, it gives more versatility for climatic conditions and engine temperatures.