This SAE Standard covers the hardness, tensile strength, and microstructure and special requirements of gray iron sand molded castings used in the automotive and allied industries. Specific requirements are provided for hardness of castings. Test bar tensile strength/Brinell hardness (t/h) ratio requirements are provided to establish a consistent tensile strength-hardness relationship for each grade to facilitate prediction and control of tensile strength in castings. Provision is made for specification of special additional requirements of gray iron automotive castings where needed for particular applications and service conditions.