Automotive Gear Oil: Properties, Functions, And Performance Standards

Automotive Gear Oil: Properties, Functions, And Performance Standards

Automotive gear oil is a specialized type of lubricant designed explicitly for transmission and differential gears in automobiles. These lubricants differ from general engine oil because they must accommodate higher loads, torque, and stress caused by frequent gear shifts and varying speeds.

Therefore, understanding the properties, functions, and performance standards of automotive gear oil is imperative for proper maintenance and improved automobile performance. In this article, we will explore the fundamentals of automotive gear oil, highlighting the significance of partnering with reputable automotive oil manufacturers in UAE.

Properties of gear oil:


Like engine oil, viscosity is a crucial property of gear oil. It refers to the oil’s resistance to flow and is typically classified by viscosity grades, such as ISO VG (Viscosity Grade) or SAE (Society of Automotive Engineers) viscosity grades. The viscosity of gear oil affects its ability to form a protective film between gear teeth and withstand high loads and temperatures.

Extreme pressure (EP) additives:

Automotive gear systems operate under extreme pressures and sliding conditions, leading to metal-to-metal contact between gear teeth. EP additives, such as sulfur-phosphorus compounds, are added to gear oil formulations to prevent wear and damage by forming a protective film on gear surfaces.

Thermal stability:

Gear oil must maintain its viscosity and lubricating properties at high temperatures to provide effective protection under severe operating conditions. High-quality gear oils with excellent thermal stability resist thermal breakdown and oxidation, ensuring prolonged service life and reliability.


Gear oil formulations should be compatible with the materials used in automotive gear systems, including ferrous and non-ferrous metals, seals, and gaskets. Incompatible oils can lead to seal degradation, leakage, and reduced performance.

Foam resistance:

Gear oil should exhibit good foam resistance to prevent the formation of air bubbles, which can impair lubrication and lead to component damage. Anti-foam additives are incorporated into gear oil formulations to minimize foam formation and ensure consistent lubrication performance.

Functions of gear oil:


The primary function of gear oil is to lubricate moving parts within automotive gear systems, including gears, bearings, and shafts. It forms a protective film between metal surfaces, reducing friction, wear, and heat generation.


Gear oil helps dissipate heat generated during operation by transferring heat away from gear surfaces. Proper lubrication and cooling help prevent overheating and thermal degradation of gear components.


Gear oil provides essential protection against wear, corrosion, and oxidation, extending the lifespan of automotive gear systems. EP additives enhance the oil’s ability to withstand high loads and extreme pressure conditions, minimizing wear and damage to gear teeth.