Understanding Base Oil Groups: Group I, II & III

Base oils are refined from crude oil, which naturally contains a mix of saturated hydrocarbons (like paraffinic and naphthenic compounds), unsaturated hydrocarbons (aromatics), and other elements such as sulfur.

Through the refining process, crude oil is transformed into three main groups of mineral base oils—Group I, Group II, and Group III—each classified based on the level of hydrocarbon saturation and sulfur content.
 

9 Group I Base Oil

• Less refined with more unsaturated hydrocarbons (aromatics)

• <90% saturates, >0.03% sulfur

• Viscosity Index (VI): 80–120

• Common in older lubricant formulations and cost-effective applications
   

9 Group II Base Oil

• Further refined with higher saturation levels

• >90% saturates, <0.03% sulfur

• Viscosity Index (VI): 80–120

• Offers better oxidation stability and performance over Group I
   

9 Group III Base Oil

• Highly refined with very high saturation

• >90% saturates, <0.03% sulfur

• Viscosity Index (VI): >120

• Considered the highest quality among mineral base oils and often used in synthetic or semi-synthetic lubricants

Each group serves different applications depending on the required performance, cost, and formulation. At Davor Sdn Bhd, we offer a wide selection of lubricants and oils formulated with the right base oil to suit your industrial or automotive needs.