Development of Automotive Lubricants Based on High-Viscosity Index Base Stock

It has long been sought to improve the low-friction properties and low-temperature viscometric characteristics of mineral oil based automotive manual transmission fluid(MTF), automatic transmission fluid(ATF), and power steering fluid(PSF).

Because, however, It has been impossible to make such improvements on the mineral oil base,synthetic oils such as poly- α -olefin have been substituted to achieve the required improvements in the lubricants. But the synthetic oils have a drawback:high cost.

Thus a new series of mineral oil based lubricants was investigated. These lubricants are made with high viscosity index mineral oil base stock that offers excellent low-temperature characteristics, which improve low-temperature viscosity (lowering of operation temperature by 5 to 10°C), a 5% reduction of friction torque in manual and automatic transmission and power steering pump and increased oxidation resistance.