The first automotive software of your lock-up principle was Packard's Ultramatic transmission, introduced in 1949, which locked up the converter at cruising speeds, unlocking if the throttle was floored for speedy acceleration or because the vehicle slowed. Together with the 3-passage torque converter, two passages are utilized for transmission oil https://rowanffdby.angelinsblog.com/33139377/5-simple-statements-about-torque-converter-clutch-explained