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Drive (top gear)

The forward-drive clutch is engaged and the engine drives the first ring gear.

The reverse clutch is also engaged, which locks the ring gear to the sun gear and both turn at the same speed.

The planet gears cannot turn, so the carrier also turns at engine speed. Output is taken from the carrier shaft, which turns at engine speed (direct drive).


How automatic gearboxes work

Epicyclic gearing explained Most modern automatic gearboxes have a set of gears called a planeta...