This SAE Standard defines the limits for a classification of engine lubricating oils in rheological terms only. Other oil characteristics are not considered or included.
This revision continues the process of extending the SAE Engine Oil Viscosity Classification system to lower high-temperature high-shear-rate (HTHS) viscosities by adding two new high-temperature viscosity grades – SAE 12 and SAE 8 – to SAE J300 with minimum HTHS viscosities of 2.0 and 1.7 mPas respectively. The benefit of establishing new viscosity grades is to provide a framework for formulating lower HTHS engine oils in support of the ongoing quest of Original Equipment Manufacturers (OEMs) to improve fuel economy.
The 100°C kinematic viscosity (KV100) ranges of the new viscosity grades overlap to provide adequate formulating space for these grades. How to assign a single high-temperature viscosity grade to an engine oil with KV100 in the overlap regions is covered in Section 6 of this document.