Reverse gear is usually marked 'R' within the selector. The forward-drive clutch is disengaged and the first ring equipment freewheels. If both Solar gears change in precisely the same direction, the World gears lockup because they can only spin in opposite Instructions. This locks the ring gear to your planets https://gearboxauto59124.blogscribble.com/33872953/everything-about-gearbox-auto