Abstract: A method for molding an annular lip type shaft seal 10 of the type having an annular elastomeric shaft seal element 12 and a resin liner 14 (preferably polytetrafluoroethylene) integrally molded therewith and bonded thereto, including providing a step or shoulder 36 on the mold core 26 to prevent the resin liner 14 from flowing axially beyond a predetermined location during molding. The method includes providing a certain range of acute angles ".alpha." between the shoulder surface 42 and the liner forming surface 38 of the mold core surface 34, and a certain range of shoulder heights "d" relative to the liner thickness "t", for various values of the initial viscosity of the elastomeric preform 18. The percentage of rejects due to undesired flow of the resin liner 14 during molding has been greatly reduced.