Maxtop hydraulic retarder oil is used as the working medium in the vehicle automatic transmission, which transmits energy through the kinetic energy of the liquid. Hydraulic transmission oil has the following characteristics: suitable viscosity, good viscosive-temperature properties, anti-wear, thermal stability and anti-oxidation stability, low temperature fluidity and anti-foam. Under frequent braking conditions, the kinetic energy of the engine is efficiently transferred to the working chamber of the retarder, and the kinetic energy of the vehicle is converted into heat energy and discharged through the cooling system to avoid overheating of the brake system. Full synthetic PAO base oil and special additives, high temperature oxidation resistance.