Patent ID: 7980995

Claim:
An electro-hydraulic control system for a transmission with a selectively operable retarder operatively connected to a transmission output member, with a retarder flow valve controlling the flow of fluid into the retarder, and with a main regulator valve for regulating main hydraulic pressure within the transmission, comprising: a selectively energizable shift solenoid; a shift valve operatively connected to the shift solenoid and movable between a first position when the shift solenoid is energized and a second position when the shift solenoid is not energized; and a pressure control solenoid valve selectively permitting control pressure fluid therethrough; wherein the shift valve multiplexes the pressure control solenoid valve to variably modulate the main regulator valve when the shift valve is in one of the first and the second positions and to permit fluid flow to the retarder flow valve when the shift valve is in the other of the first and second positions.