Patent ID: 8371988

Claim:
An electro-hydraulic control for a multi-speed vehicle transmission, comprising: an electrical control configured to receive shift request signals from an electronic range selector of the transmission, first, second, and third electro-hydraulic actuators each configured to receive electrical signals from the electrical control, first, second and third shift valves each being in fluid communication with the first, second, and third electro-hydraulic actuators to receive pressurized hydraulic fluid output by the electro-hydraulic actuators and being in fluid communication with each other to selectively deliver pressurized hydraulic fluid to at least one shift mechanism of the transmission, a fourth electro-hydraulic actuator configured to receive electrical signals from the electrical control, a fourth shift valve configured to selectively deliver pressurized hydraulic fluid to at least one shift mechanism of the transmission, the fourth shift valve being controllable by the fourth electro-hydraulic actuator to achieve a first position when the fourth electro-hydraulic actuator is not electrically actuated and a second position when the fourth electro-hydraulic actuator is electrically actuated, and a plurality of fluid passages selectively coupling the first, second, third, and fourth shift valves such that a neutral or reverse range can be achieved by the transmission when the fourth shift valve is in either the first position or the second position and a forward range can be achieved by the transmission only when the fourth shift valve is in the second position.