The Protection Of Synthetic Gear Oil

Although gear oil, like engine oil or automatic transmission fluid, acts as a lubricant for moving mechanical parts, it also plays other important roles in it's applications. A manual transmission, or gearbox, and differential in a vehicle distributes the power created by it's engine to the wheels. It does this with a series of gears which engage and disengage to deliver the desired speed at the wheels. Gear oil acts as both a lubricant and a small layer of protection between the teeth of these gears. Only a few teeth of the gears are in contact at any given moment. This means that there is an intense pressure from the full weight of the engine power on the face of these few gears. Gear oil must be a specific composition and viscosity in order to provide this protection and keep gear wear from occurring. It must be able to withstand high temperatures and these extreme pressures over time while continuing to form a thin protective film between the teeth of these gears.
Traditional, petroleum based oils are refined from crude oil, and this refining process leaves behind an unstable substance that is full of byproducts. Also, the process of refining petroleum oil produces molecules of different types and sizes. Conventional gear oils tend to break down in high temperatures and under heavy friction loads over the time between regular services. Synthetic gear oils are chemically engineered by scientists, in a laboratory, to have a uniform molecular structure and a cleaner composition. These oils last longer when faced with the high temperatures and constant frictions inside a gearbox or differential. Gear boxes and differentials have longer drain intervals than a vehicle's engine or automatic transmission which means synthetic gear oils protect the gears from wear better over this extra length of time.
Because synthetic gear oils can be engineered for more precise viscosities and stay thicker, longer over time, they are better for protecting gear faces consistently. Besides protecting these gears better over time, synthetic gear oil will not leave behind as many byproducts, called hydrocarbons like conventional oils. These byproducts contaminate the fluid over the course of the longer drain interval, changing the viscosity of the fluid, and again, create more wear on gear faces. This wear comes in the form of pitting and scoring. This happens when gears shed metal flake into the fluid, creating even more problems for viscosity uniformity. Synthetic oil stops this terrible cycle from occurring and protects the gears in these vital vehicle components.