S (stall level): During this stage the turbine speed is zero along with the impeller is rotating; the efficiency during the stall stage is minimum amount, all around 50%, meaning that half of the facility coming through the motor is lost by way of friction and dissipated as warmth; at https://torqueconverterclutch64950.ttblogs.com/13920953/the-5-second-trick-for-torque-converter-clutch