The Application of Antioxidant Analysis to Transmission Fluid Testing

The determination of the total antioxidant capacity of new and used automatic transmission fluids can yield information useful in the study of fluid stability, severity of service and correlation between bench tests and service. The technique is particularly useful in the characterization of the earlier stages of fluid oxidation where parameters such as T.A.N., pentane insolubles and viscosity yield little information. Three fluids from a fleet test manifested different antioxidant decay profiles. Data obtained from a laboratory beaker test indicate that some test conditions can reproduce these decay curves and thus simulate the primary oxidation processes occurring in the transmission in this fleet.