Operation CHARM: Car repair manuals for everyone.

Drive Rang. - First Speed

With the selector lever in Drive range, the forward clutch is applied. This delivers turbine torque to the mainshaft and turns the rear internal gear in a clockwise direction.

Clockwise motion of the rear internal gear causes the rear pinions to turn clockwise to drive the sun gear counterclockwise. In turn, the sun gear drives the front pinions clockwise, thus turning the front internal gear, output carrier and output shaft clockwise in a reduction ratio of approximately 2.5 to 1. Reaction of the front pinions against the front internal gear is taken by the reaction carrier and roller clutch (low sprag on early units) to the transmission case. Approximate stall ratio is 5 to 1.