The primary automotive software with the lock-up theory was Packard's Ultramatic transmission, introduced in 1949, which locked up the converter at cruising speeds, unlocking in the event the throttle was floored for speedy acceleration or given that the vehicle slowed. A torque converter are unable to achieve 100% coupling effectiveness. https://eduardodsdmx.ssnblog.com/33065758/torque-converter-clutch-for-dummies