National Bureau of Standards Special Publication 556. Proceedings of ESTABLISHING SUBSTANTIAL EQUIVALENCY FOR MOTOR OILS J. J. Come ford Recycled Oil Program Institute for Materials Research As the first speaker on the panel, I would like to discuss some of our concerns in the area of test procedures for gasoline and diesel engine lubricating oils. I would also like to ask some questions which we believe should be addressed by the industry (and on which we hope other panel members will comment), as well as direct our attention to areas of concern of industry. First I will briefly review some basic nomenclature for motor oils. Most of this material has been touched on at some point during the conference, but I believe it would be useful to briefly review it at this point. Table 1 shows the American Petroleum Institute (API), Society of Automotive Engineers (SAE), and American Society for Testing and Materials (ASTM) engine service classification system for gasoline engine oils. Note that oil meeting SA quality classification contains no additives and is unsuitable for current gasoline engines. The SE grade, the most highly formulated in terms of additive content, meets present engine manufacturers warranty requirements. What is not apparent from this table but which should be kept in mind is the SE classification. For example, this classification implies that the oil, if subjected to a prescribed and costly series of tests on laboratory engines, will achieve certain minimum ratings in terms of performance. Some of the performance parameters include engine sludge rating, varnish rating, bearing weight loss, etc. These tests are described in the SAE J183a standard and also in the ASTM engine sequence tests. Table 2 lists the commercial and fleet classifications or diesel engine service. Some oils are labeled as meeting both services, such as SE/CC or SE/CC/CD. Note that CC oils meeting MIL-L-46152 also meet SE, and CD oils meeting MIL-L-2104C also meet service SC. The sequence tests contain many different single- and multi-cylinder engine tests. Some of the tests are no longer available in the classes other than SE/CC/CD. Modern engine oils must be capable of dealing with a complex mixture of contamination products. In addition to reducing wear and dissipating heat, the oil must deal with these products, some of which are listed in table 3. These products cause a variety of problems for the engine and require carefully selected additive packages for the base oils to deal with them. To evaluate basestocks and formulated oils, a variety of laboratory tests are used. At the present time, however, an accurate prediction of performance appears to require both engine sequence tests and field tests. The Environmental Protection Agency/Department of Defense project described earlier on re-refined oils using existing methodology is one approach to the problem. What correlations exist and how good they are pose questions that should be considered. In considering these questions, the following aspects may be considered: • Can physical and chemical tests adequately monitor the re-refined basestock output of a re-refiner? • Can laboratory "bench tests" adequately monitor nerformance in What does "substantially equivalent" mean for SA oils? For Is the "additive response" of a basestock of serious concern for 1 Underlined numbers in brackets indicate the literature references at the end of this paper. To summarize the various aspects of this problem, it would appear to me that we need to determine how best to measure substantial equivalency in terms of tests defining equivalency for re-refined and virgin oils and to correlate these tests with actual performance. References [1] Kreuz, K. L., Gasoline Engine Chemistry as Applied to Lubricant Problems, Lubrication, 55, 53 (1969). National Bureau of Standards Special Publication 556. Proceedings of ACTIVITIES OF THE SAE FUEL AND LUBRICANTS TECHNICAL COMMITTEE Charles F. Schwarz I would like to report to you the latest activity of the Society of Automotive Engineers (SAE) Fuel and Lubricants Technical Committee, and, as I am the official liaison between the SAE and the National Bureau of Standards Recycled Oil Program, I will report on this meeting to the next SAE Fuel and Lubricants Technical Committee. One item of interest to this group is that the Fuel and Lubricants Technical Committee will request the American Society of Testing and Materials (ASTM) to develop a test method which incorporates high-temperature, high-shear viscometrics, or other rheological characteristics which predict the performance of both single and multigrade (i.e., both Newtonian and viscosity index improved) engine oils in engine bearings and/or the ring and cylinder area. wear. On September 8, 1977, the SAE wrote a letter to the ASTM and the American Petroleum Institute (API) officially requesting that a new gasoline engine oil category be established to include SE performance, plus "long drain" capabilities and new antiwear requirements. Previously, the SAE had two active task forces working towards two possible new categories: (1) a long-drain oil, and (2) oils having improved antiThe two task forces have been combined and now recommend a single new category. The SAE requests that (1) the ASTM develop the performance criteria for the proposed category, and (2) the API develop the user language. Another area of active programs is the viscosity classification task force under Subcommittee 2 of the Fuel and Lubricants Technical Committee. Samples are being collected from oil companies, including re-refiners, to determine what viscosity ranges exist within a given W-grade engine oil at temperatures other than -18° C. The need for such a survey arose from an earlier survey of major engine builders throughout the world to determine their low-temperature starting and pumpability using a single commercial oil of unknown (to them) viscosity characteristics. Tests are then conducted at a near-the-minimum recommended use temperature for the particular viscosity grade, rather than at 0° F (-18° C) where engine oils are currently classified. Because of the probable difference among oils at temperatures other than 0° F, the present classification may be limited in meeting the needs of the engine builders and the users. From the estimated 1,000 samples, a random statistical sample of about 100 oils will be selected for analysis. Analysis will be conducted by an independent testing laboratory at a cost of approximately $15,000. These tests will include CCS, as well as other pumping tests now being studied by the ASTM. For the immediate future, the Fuel and Lubricants Technical Committee has requested that the units of centiposes (CP) and centis tokes (cSt) be used for the viscometric unit of viscosity by the SAE until further clarification was obtained. The ASTM requested that the SAE take necessary action to reflect the tentative 1H2 and 1G2 test passing limits; Mr. J. A. MacLean has agreed to review these limits early in 1978 and to provide Subcommittee 2 with a recommendation for the revision of J-183b. In addition, a new task force within the Fuel and Lubricants Technical Committee would be formed to recommend that action be taken on the request from the ASTM to handle absolute categories and test procedures. The task force will also consider what means should be used to keep categories current. A new task force was formed entitled "Low Temperature Viscosity of Used Engine Oils." The report is due in March 1978. A new task force on Fuel Saving Engine Oils has been formed; there is no report at this date. At the last Fuel and Lubricants Technical Committee meeting, considerable discussion was generated about the Engine Oil Review Board. At the request of the Army, |