What Is Shear Stability?
The ability of a substance to retain its original properties under shear. The shear stability of lubricating oils represents the property of lubricating oils to maintain a stable viscosity when subjected to mechanical shearing and rolling. Also known as mechanical stability. If the shear stability is good, the lubricating oil can maintain a relatively stable viscosity during mechanical shearing, otherwise the lubricating oil will have a lower viscosity due to shearing.