Development of Type F Automatic Transmission Fluids

The development of a Type F automatic transmission fluid is presented by discussing the three components of a typical fluid: the base oil, the viscosity index improver, and the additive package. The trend towards fluids with improved oxidation stability and frictional characteristics is demonstrated by illustrating the three levels of performance required by the three major changes in Ford specifications over the past several years. This paper shows that development and evaluation of automatic transmission fluids have become quite complex and that it is now necessary to run a wide variety of bench, transmission, field, and proving ground tests. In addition, the development and properties of an additive package which exceeds the M2C33 E-F specification are described.