One-Way Clutch Low-Reverse
The low-reverse one-way clutch, shown in the following illustration, holds the reverse planetary carrier stationary to the case in first gear. The inner race of the low-reverse one-way clutch is bolted directly to the case. The outer race is splined to the reverse clutch hub, which is splined to the reverse planetary carrier.
In first gear, the center shaft drives the forward ring gear clockwise by way of the forward clutch. With the forward planetary carrier providing a counterclockwise resisting torque, the forward/reverse sun gear is driven counterclockwise.
As the sun gear is turned counterclockwise and the reverse ring gear is turned counterclockwise by the resistance of the vehicle, the reverse planetary carrier is also turned counterclockwise. Because the reverse planetary carrier is prevented from turning counterclockwise by the low-reverse one-way clutch, the torque is transferred from the sun gear to the reverse ring gear and the output shaft. During coast, the planetary carrier is allowed to overrun and spin clockwise.
The low-reverse one-way clutch overruns in second, third and fourth gears. In these cases the forward/reverse sun gear is stationary while the reverse ring gear turns clockwise with the output shaft. This turns the reverse planetary carrier clockwise, causing the low-reverse one-way clutch to run clockwise and overrun.