Frankol 5W40 CK-4/SN Fully Synthetic series oils are fully synthetic lubricants for heavy duty engines that work efficiently at severe conditions or climate. These are designed to provide excellent wear protection. The powerful ability of the Frankol 5W40 oils to adapt to adverse temperatures aids it to maintain viscosity and produce brilliant performance in highway heavy duty engines that function under severe conditions. Also, the Frankol 5W40 oils consist of field proven additive technology that maximizes engine wear control and provides exceptional engine cleanliness. The API CK-4 requirements and firm OEM specifications are surpassed by metal anti-wear protection, and the strain on equipment startup is lowered due to its ultra-low pour points and fine fluidity.