The test method is designed to predict the high temperature deposit forming tendencies of an engine oil. This test method can be used to screen oil samples or as a quality assurance tool.

FIG. 1 Thermo-oxidation Engine Oil Simulation Test (TEOST)

1.1 This test method covers the procedure to determine the amount of deposits formed by automotive engine oils utilizing the thermo-oxidation engine oil simulation test (TEOST). An interlaboratory study has determined it to be applicable over the range from 10 to 65 mg total deposits.

Note 1—Operational experience with the test method has shown the test method to be applicable to engine oils having deposits over the range from 2 to 180 mg total deposits.

1.2 The values stated in SI units are to be regarded as the standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.