Van Doorne CVT Fluid Test: A Test Method on Belt-Pulley Level to Select Fluids for Push Belt CVT Applications

Since the market for continuously variable transmissions (CVTs) is expanding rapidly and customer demands become more and more specific, there is an increasing need for adequate CVT fluids. In order to develop and apply new fluids, it is necessary to have reliable methods for fluid testing. However, test methods and standards that are being used nowadays for automatic transmission applications are not sufficient to select fluids for push belt CVT applications since they do not incorporate the belt-pulley behaviour. In this paper a method is described to test fluids on a belt-pulley level. The test method comprises full load testing in several ratios in which durability and functionality related push belt CVT items are being examined. This Van Doorne CVT Fluid Test can be used in addition to existing fluid tests in order to determine the suitability of fluids for push belt CVT applications.