Industrial and mobile equipment operating in cold temperatures require specific lubricants that can handle the stresses put on machines by winter weather and/or freezing conditions. Though these lubricants are primarily used in cold temperatures, they may often be used year-round, in varying climates with much success. These increased performance characteristics can be attributed to the High Viscosity Index of these oils.
ISO VG 68 oil has a midpoint kinematic viscosity of 68 mm2/s, also referred to as centistokes (cSt). The midpoint is derived by taking the average of both the minimum and maximum kinematic viscosities. In the case of ISO VG 68 oil, those numbers are 61.2 cSt and 74.8 cSt, respectively. These numbers refer to the standard testing mechanisms used to determine how much resistance to flow (i.e. viscosity) these oils demonstrate.