Super S 303 Tractor Hydraulic Fluid is formulated from a blend of highly refined base oils with a superior additive package. It is designed to lubricate the transmission, differential and final drive gears in tractors and implements. Every batch of Super S 303 is tested in our on-site lab to assure premium quality and performance.Misapplication may cause severe performance problems. 303 Tractor Hydraulic Fluid has not been recommended by any OEM for model years later than 1974. For equipment built after 1974 requiring multi-functional fluid, use Super S Premium Universal Tractor Hydraulic Fluid (J20C).