Abstract
Today's powertrain engineers rely upon rotary seal rings to control the hydraulics that activate the various clutches within the typical automatic transmission. Over the past two decades, polymeric seal rings have become a material of choice in most transmission designs. Along with a variety of polymeric materials to choose from, many different seal ring gap configurations can be used to provide the right amount of leakage needed for each application. A combination of the right material and gap geometry can provide a tailored solution for every rotary seal ring application in the transmission.