Development of a Variable-Severity Scoring Test for Hypoid Gear Lubricants

The presently used laboratory hypoid gear scoring tests are described and the deficiencies are noted. The inadequacies of these tests led to the development of a test device and a procedure designed to evaluate gear lubricants more accurately. An account of the development of the test system with the cooperation of the Coordinating Research Council, Inc. (CRC) is given. The unique design features of the gearbox and the test gears are described.

An account is given of the steps in the test development and the use of the CRC reference oils in this development. The test is capable of evaluating the scoring resistance of hypoid gear oils covering a range of performance levels from RGO 104 to RGO 110. Data on repeatability are presented.