Because of their special molecular structure, synthetic lubricating oils based on poly-alphaolefins (a type of SHC) and polyglycols ensure that tooth-related friction is considerably lower than with mineral oils. It may be up to 30 percent lower than if a regular mineral gear oil with EP additives was used. Because the friction coefficient of synthetic oils is lower, tooth-related friction is reduced, thus increasing the gear’s efficiency.
The efficiency of gears with a high sliding percentage, worm and hypoid gears, for instance, may increase up to 15 percent if a synthetic oil is used instead of a mineral oil. Even in the case of spur, helical and bevel gears (which have a naturally high gear efficiency), it is possible to increase gear efficiency of up to one percent by using a synthetic gear oil. This may not seem like much at first, but it may result in considerable cost savings depending on the nominal output of the gear unit, especially in the case where several gears are deployed.