A centrifugal clutch is splined to the turbine by a one-way clutch. As vehicle speed increases, the hydraulically driven turbine and the lock-up clutch splined to it turn with increasing speed. The centrifugal force on the clutch shoes increases as the clutch assembly turns faster and faster.

When the turbine and lock-up clutch are turning fast enough, centrifugal force causes the clutch shoes to move outward until they contact the inside surface of the converter cover. The face of each shoe “grabs” the cover and locks it to the turbine.

As vehicle speed drops, turbine speed and centrifugal force are reduced. The return springs retract the clutch shoes, the cover is released, and the turbine again becomes hydraulically driven.

A one-way clutch drives the clutch assembly. With the clutch engaged, the driver may release the accelerator pedal slightly, allowing the vehicle to “coast.” This allows the engine and input shaft to turn at different speeds.

The friction shoes cannot release during coasting because centrifugal force holds them against the cover. Instead, the damper one-way clutch releases so the input shaft can turn faster than engine speed. When the driver accelerates, the damper one-way clutch again locks the turbine to the clutch and damper assembly.

Scroll over the question marks for more information.