The Turbo Glides under normal driving conditions was essentially a single speed, the torque converter acted as a gear reduction during acceleration, hill climbing, etc, similar to the Buick Dynaflow. There were in a sense precursors to the CVT that Nissan uses.
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Turboglide and dynaflow both had planetary gear sets and multi-disk clutch packs to achieve reduction.
The torque converter allows the engine to over-speed the driven torus, which converts velocity to pressure by return flow of the moving oil, thus increasing torsional force.
Much energy is lost as heat in that process, which is why modern transmissions use variable reduction gear sets rather than large torque converters.
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Ah yes, good ol' Dynaflow.
Had a '53 Buick as a teenie bopper.Straight 8 w/ Dynaflow. Very comfortable couchlike front seat. :)
BTW, how reliable are these CVT transmissions? Do they use variable pulleys and belt?