Quick Lubes Question GF-4 Oil Quality


The engine sequence test used to measure motor oil’s contribution to passenger car fuel economy is a cause for “extreme concern,” says a letter from the fast-lube industry. It asks the oil industry for assurance that new GF-4 engine oils passing the test will perform as expected.

The letter followed on the heels of an Oct. 20 Lube Report article which asked, “Why would two distinct GF-4 passenger car motor oils — which earlier had passed the rigorous Sequence VIB (‘Six B’) engine test for fuel economy — repeatedly flunk the same test now?” Two GF-4-approved oils had been submitted by motor oil companies for use as potential Six B reference oils, the article noted. But each oil had been tested five times and neither had mustered a passing grade in the difficult engine sequence test. Since each Six B test run costs almost $25,000, the streak of 10 failures was both costly and awkward for the lubricants industry.

Following that report, Stephen M. Christie, executive director of the Automotive Oil Change Association in Dallas, Texas, wrote to the American Petroleum Institute and ASTM to express his group’s dismay at the inability of approved oils to pass the test. AOCA’s 1,000 member companies operate some 3,500 U.S. and Canadian lube centers.

“It has come to AOCA’s attention that GF-4 5W-20 motor oil recently failed to pass a series of Sequence VIB engine tests for fuel economy at multiple laboratories,” Christie wrote on Oct. 20. “While we are aware that some failures occur during routine equipment testing, the widespread level of failure in this case is of extreme concern to us. Motor oil suppliers have already begun distributing GF-4 motor oils to the exclusion of the less expensive GF-3 motor oils, which are still validly licensed products until April 2005.

“If there is a problem with GF-4 5W-20 motor oil, it needs to be corrected immediately before any further unnecessary risk and expense are incurred by the fast lube industry and its customers,” AOCA’s letter urged.

It further requested “that API provide AOCA with written verification regarding the validity of all tests relied upon for the certification of GF-4 motor oils as well as an explanation as to how API plans to verify that the GF-4 motor oils on the market today still meet the standards of the required tests. AOCA further requests a formal acknowledgement that API will hold the fast lube industry harmless from any liability caused by defective GF-4 products.”

AOCA sent a similar letter the same day to John Zalar of ASTM’s Test Monitoring Center. PerkinElmer’s Tom Franklin, chairman of ASTM’s Subcommittee B on Automotive Lubricants, wrote back on Oct. 27.

“In your letter of October 20, 2004 to Mr. John Zalar on the referenced subject, you made two requests of ASTM; 1) ‘provide AOCA with written verification regarding the validity of all previous tests relied upon for the certification of GF-4 motor oils,’ [and] 2) ‘an explanation as to how ASTM plans to respond to the test failures and whether ASTM’s plan will verify that the GF-4 motor oils on the market today still meet the standards of the required tests.’ I will attempt to provide a useful answer to these questions,” Franklin wrote, “but let me add some clarity to the position of ASTM with regard to engine oil performance specifications in general and GF-4 in particular.

“Historically, passenger car engine oil specifications used by the API in their engine oil category system have been developed within ASTM by the ASTM D02.B Passenger Car Engine Oil Classification Panel (PCEOCP). These were subsequently published in ASTM D 4485, Standard Specification for Performance of Engine Oils.

“In the case of GF-4, this specification was developed outside of the ASTM consensus process by ILSAC/Oil.

“The ASTM Test Monitoring Center (TMC) provides a calibration service to those laboratories that supply performance data for product verification in tests such as the Sequence VIB. To accomplish this, the TMC provides known reference oils to the laboratories and receives the test results on those reference oils. If the results fall within the established acceptance band the test stand/lab is considered calibrated for the period of time spelled out in the test procedure. In the case of the VIB, laboratories are permitted to run up to seven non-reference oils between calibration tests. The TMC does not review or in any way act upon data for non-reference oils. Validity of reference and non-reference oil tests is determined by the individual laboratories against rigorous standard test methods.

“The American Chemistry Council Product Approval Code of Practice and API 1509 both require that tests, such as the Sequence VIB, be run in test stands calibrated by the ASTM TMC calibration process.

“In answer to your questions then,” Franklin continued, “1) ASTM calibration results and test validity verification would be available for the laboratory and stand in which product qualification took place. However, only the parties involved in the qualification can provide those records. It is reasonable to assume that given the ACC and API requirements that these tests were run in calibrated test stands.

“2) The ASTM PCEOCP has this question under consideration but a simple resolution seems unlikely.”

“My own observations,” Franklin’s letter concluded, “based upon the statistical variations that exist for the Sequence VIB test and the current industry ratio of passes to fails, are that a) products qualified using the Sequence VIB meet the letter of the GF-4 specification with respect to fuel economy, and b) these oils will provide your customers with the best fuel economy available with current lubricant technology.”

API’s Lubricants Committee considered AOCA’s letter at its Nov. 8 meeting in Houston. It agreed that a response was in order, but yesterday said it had not yet prepared one.

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