What is the Difference Between Engine Oil and Transmission Fluid?

[DelJulianna]

Engine oil and transmission fluid are not the same. Below are the specific differences between the two: 1. Different Functions: Automatic transmission fluid is specifically designed for automatic transmissions. The specialized fluid used in modern automatic transmissions serves as both the hydraulic fluid for the torque converter and the lubricant for the planetary gear structure, as well as the hydraulic fluid for the shifting mechanism. Engine oil, on the other hand, plays roles such as lubrication and friction reduction, auxiliary cooling, sealing and leak prevention, rust and corrosion protection, and shock absorption. It is often referred to as the 'blood' of a car. 2. Different Characteristics: Automatic transmission fluid has appropriate viscosity; excellent thermal and oxidation stability; good anti-foaming properties; strong anti-wear performance; good compatibility with rubber sealing materials in the system; and superior anti-corrosion (anti-rust) properties. Engine oil has appropriate viscosity and certain performance requirements, including oxidation resistance, wear resistance, corrosion protection, and viscosity-temperature characteristics.