Is Transmission Fluid the Same as Gear Oil?
1 Answers
Transmission fluid and gear oil are not the same. They differ in viscosity and properties, and must be used correctly without confusion. The specific details are as follows: Transmission fluid, also known as Automatic Transmission Fluid (ATF) or automatic transmission oil, is used as a working medium in vehicle automatic transmissions composed of hydraulic torque converters, hydraulic couplings, and mechanical transmissions. It transmits energy through the kinetic energy of the liquid. Gear oil is primarily made from petroleum-based lubricating oil or synthetic lubricating oil, blended with extreme pressure anti-wear agents and oiliness agents to form an important lubricating oil. It is used in various gear transmission devices to prevent tooth surface wear, scuffing, sintering, etc., thereby extending their service life and improving power transmission efficiency. Gear oil should have excellent anti-wear and load-bearing properties, as well as appropriate viscosity. Additionally, it should possess good thermal oxidation stability, anti-foaming properties, water separation performance, and rust prevention. Since gear loads generally exceed 490 MPa, and hypoid gear surface loads can reach up to 2942 MPa, extreme pressure anti-wear agents are often added to gear oil to prevent oil film rupture and subsequent tooth surface wear and scuffing. Sulfur-phosphorus or sulfur-phosphorus-nitrogen additives are commonly used. Transmission fluid cannot replace gear oil. Due to its low viscosity and the addition of large amounts of high-boiling-point organic solvents, it cannot be used as a substitute for mechanical lubrication oil.
