larger image Castrol Heavy Duty Antifreeze with SCA is designed to provide superior engine protection for heavy-duty cooling systems. For years, heavy-duty operators were limited to using low silicate automotive/heavy duty antifreezes that required the addition of a separate supplemental coolant additive (SCA) at initial fill and top off. While this was effective, it resulted in mixing errors when the SCA was added. To prevent SCA variability caused by mixing errors, and improve convenience, Castrol Heavy Duty Antifreeze with SCA was developed. Castrol Heavy Duty Antifreeze is a fully-formulated universal formula antifreeze, having the advantages of low total dissolved solids, low silicate, and incorporates nitrite to provide superior wet sleeve liner cavitation protection. Since Castrol Heavy Duty Antifreeze with SCA is pre-charged with SCA, there is no need to add additional SCA's at initial fill or when topping off to compensate for SCA dilution. Additional advantages of Castrol Heavy Duty Antifreeze with SCA include its phosphate-free formula that reduces the risk of scale and state of the art corrosion inhibitors, which eliminates the need for expensive deionized water. As an added benefit, Castrol Heavy Duty Antifreeze with SCA meets the performance requirements of most major automotive specifications for conventional antifreeze, allowing operators of mixed fleets to stock one antifreeze for all their vehicles, simplifying fleet maintenance procedures.