An automatic transmission providing variable speed ratio and reverse drives between drive and driven shafts and including friction-engaging devices, in the form of friction clutches and brakes, for establishing the drives. The devices are operable by hydraulic servomotors, certain servomotors each having first and second pistons arranged in tandem, with the first piston being movable by hydraulic fluid to engage the associated friction device, the second piston being movable by hydraulic fluid to also move the first piston during the application of hydraulic fluid to the first piston to thereby substantially double the effective area of the pistons of the servomotor to provide additional increased pressure to the engaged friction device. The transmission also includes an hydraulic governor fixed to the driven shaft by a locking spring clamp connector positively holding and keying the governor to the shaft in a simple assembly operation and in a manner to insure sealing between fluid-passage ports in the shaft and in the governor body for transfer of activating hydraulic fluid.