The
powertrain of a six-speed
powertrain and a
hydraulic control system includes a main shift section of first and second single
pinion planetary gearsets, in which a first
planet carrier is fixedly connected to a second ring gear. The
powertrain also includes a first ring gear fixedly connected to a second
planet carrier, and a first sun gear. The second
planet carrier, and a second sun gear are variably connected to an input shaft through first, second, and third clutches, respectively. A connecting member connecting the first ring gear and the second planet carrier is variably connected to a housing through a first
brake and a first one-way
clutch. The second sun gear being variably connected to the housing by a second
brake. The powertrain also includes a secondary shift section realized through a third single
pinion planetary gearset, in which a third sun gear is connected to a third planet carrier via a fourth
clutch, and is also connected to the housing through a third
brake and a second one-way
clutch.