Is Your Grease Expert Really an Expert?

John Kay, Stratco Inc. Tom Steib, Elco Corp.

Looking for a grease expert? The best means of ensuring quality of professional services or products are through certification programs.

The National Lubricating Grease Institute (NLGI) has provided a forum for research and education and has actively participated in the development of technical standards since its inception.

As a natural extension of these activities, NLGI also manages programs for professional certification as well as product certification for automotive greases.

The NLGI offers education courses that provide a wide spectrum of knowledge related to lubricating greases. Instruction topics include manufacturing methods, chemistry of ingredient (base oils, additives, thickener reactants), grease types, grease applications, grease properties and testing, and the grease market. The NLGI also publishes a Grease Guide that provides basic information in many of these areas.

The information provided in the courses, along with the literature, furnishes the basics necessary to establish a standard of expertise in the lubricating grease field. In order to qualify individuals possessing this level of know-how, NLGI established the Certified Lubricating Grease Specialist (CLGS) certification program.

Grease Specialist Exam

The Certified Lubricating Grease Specialist is required to pass a two-hour exam, which covers all of the topics mentioned above. The test is offered at the NLGI annual meetings and other times and places as deemed necessary.

The CLGS certification is renewable every three years. Specialists are identified on the NLGI Web site, where more detailed information and applications are available. The CLGS credentials represent an excellent tool for employers to screen employees and end-users to ensure consultants and suppliers are properly qualified in the field.

Product certifications are also critical to end-users and original equipment manufacturers (OEM). In the past, the diversity of specifications for automotive service greases, as established by the original OEM, made it difficult for the marketer of lubricating greases to make available all the many specified products.

Creating a Standard

Finally, the Society of Automotive Engineers, the American Society for Testing and Materials and NLGI, forming a tripartite group, all played their respective roles in establishing ASTM D 4950 as a standard for automotive service greases. As a result, OEMs, suppliers and consumers have a common language to use when describing lubricating greases for automotive service.

ASTM D 4950 includes specifications for two category groups: chassis lubricants ("L" prefix) and wheel-bearing lubricants ("G" prefix). Performance classifications within these groups result in two designations for chassis greases (LA and LB) and three designations for wheel bearing greases (GA, GB and GC). The automotive industry is in general agreement that the highest performance category, to date, in each group (LB and GC) is suitable for service relubrication.

Following the development of these categories, the NLGI implemented its service classification as a means of identifying to the consumer the two highest performance levels: GC and LB; the combination, GC-LB, represents a multipurpose category. In the future, NLGI will revise the system concurrently with any changes made to ASTM D 4950.

An Identifying Mark

To facilitate easy, accurate identification to all users, NLGI has made available to the industry an identifying symbol, the NLGI certification mark, to be displayed on grease packaging. Those OEM owner's manuals that illustrate this mark will advise users to use only those greases carrying this mark on the label.

The license to use the NLGI certification mark is available to both NLGI members and nonmembers. Currently, there are 215 certified products from 60 companies carrying the mark. Further information on the application procedure can be obtained at

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