The torque converter clutch will come into motion to mitigate the inherent inefficiency in the fluid coupling at larger speeds. The stator sends the fluid coming back from the turbine to the pump. This enhances the performance with the torque converter. Note the spline, that is connected to a 1-way https://myleshvzay.ja-blog.com/34337323/the-2-minute-rule-for-torque-converter-clutch