Through a torque converter, engine power is transmitted to the input shaft (1). Both the forward and reverse sun gears are mounted on the input shaft and always rotate when the input shaft is driven.
The center carrier (2) connects the input and the output shaft, and is the carrier for the planet gears for both the reverse set and the second speed set. The sun gear for the second speed is mounted on the center carrier.
The sun gear for first speed is mounted to the output shaft (3). The output shaft is mounted on the center carrier.