Base oils are used to make various lubricants and greases across all industries. Base oils can represent from 75% to 99% of a finished lubricant. These might be automotive engine oil, grease or metal processing fluids.

A base stock manufacturer is the entity that defines the product identifier, specifications and quality management system of base stock(s) which are produced at one or more manufacturing sites.
An oil marketer is the marketing organization responsible for the integrity of the brand name and the representation of a branded product in the marketplace. Oil marketers own the product specifications of a formulated lubricant and are responsible for the representation of a lubricant’s performance. An oil marketer may contract with a lubricant blender to blend products meeting their specifications.
ExxonMobil is both a base stock manufacturer and an oil marketer.

Group I base oils are the least severely refined and make up the bulk of the base oil market. They are generally used in broad applications such as industrial lubricants, gear oils and marine.

Group II base oils have less sulfur and are usually more stable than Group I base oils, which gives them a wider range of uses in high-performance situations. They are often used in automotive and heavy-duty engine oils as well as in industrial lubricant and other applications.

Group III base oils are used primarily in higher tier, low viscosity engine oils, although they have found increasing use in premium industrial lubricants. The low viscosity of Group III base stocks limits their applicability to a broad range of industrial lubricant applications.

Polyalphaolefin Group IV base stocks span a range of viscositiesand are used in a variety of applications. Group IV stocks are generally used in flagship-type products demanding the highest level of performance.

CORE™ base stocks part of a slate of Group I base stocks offered globally by ExxonMobil. They offer broad blending coverage with performance capabilities in a wide range of applications from industrial lubricants to engine oils.

EHC™ base stocks are a slate of Group II/II+ base stocks offered globally by ExxonMobil. The lower sulfur content and higher viscosity index of EHC™ Group II/II+ base stocks allow them to be utilized extensively in automotive and diesel engine oils as well as industrial applications where formulations benefit from the increased oxidation stability, higher VI and better low temperature performance.