Diesel Data: Automotive Repair

One-Way Clutch

DESCRIPTION
The one-way clutch (O.W.C.) is a Sprague type. Two clutches are used. One is mounted between the one way clutch outer race and the rear internal gear assembly. The other is located between the forward clutch drum and the one-way clutch inner race.





OPERATION
The former O.W.C. (3-4) is provided to prevent counterclockwise rotation (as viewed from the front) of the rear internal gear assembly of the rear planetary gear during 1st, 2nd and 3rd speeds of the "D" range, "3" range, "2" range and "1st range". At the 4th speed of the "D" range, therefore, the rear internal gear assembly rotates clockwise so that the O.W.C. rotates freely to ensure smooth transition between 3rd and 4th speeds.

On the other hand, the latter O.W.C. (1-2) is provided to prevent counterclockwise rotation (as viewed from the front) of the forward clutch assembly during 1st speed of the "D" range and 1st speed of the "3" range. Therefore, when shifting from 1st speed of the "D" range or "3" range to 2nd speed, the forward clutch assembly rotates clockwise. As a result, the O.W.C. now rotates freely ensuring smooth transition between 1st and 2nd speeds.