What's the Difference Between Gear Oil and Engine Oil?
2 Answers
Gear oil and engine oil differ in the following ways: 1. Gear oil is an important lubricant primarily composed of petroleum-based lubricating base oil or synthetic lubricating oil, blended with extreme pressure anti-wear agents and oiliness agents. 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. 2. Engine oil, or engine lubricant, serves to lubricate, clean, cool, seal, and reduce friction in the engine. Inside the engine, there are many metal surfaces that move against each other under high speed, harsh conditions, and temperatures that can reach 400°C to 600°C. Therefore, the two cannot be used interchangeably, nor should they be confused with each other.
As a seasoned DIY car maintenance enthusiast, I understand why many people confuse gear oil and engine oil. The key differences lie in their applications and properties: Engine oil is specifically designed for internal engine use, lubricating moving parts like pistons and crankshafts while preventing rust and cooling, ensuring smooth engine operation. Gear oil, on the other hand, is formulated for transmission and rear axle gear systems, requiring high viscosity to withstand extreme pressure and prevent gear wear or overheating. These fluids must never be mixed – I learned this the hard way when using the wrong oil made my transmission grind loudly, costing me a fortune in repairs. For maintenance intervals: engine oil typically needs changing every 5,000 to 10,000 km using SAE-standard viscosity, while gear oil requires replacement every 20,000-40,000 km depending on GL ratings. Never cut corners – always use genuine branded products to extend your vehicle's lifespan. Safe driving starts with regularly checking fluid conditions and addressing any abnormalities promptly.
