F 250 4WD LD Pickup V8-5.4L SOHC VIN L (1997)
Clutch: Description and Operation
Low Reverse Clutch
E4OD
The low-reverse one-way clutch 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.
