Abstract: A method of operating a hydraulic retarder includes directing fluid from a retarder pump to the retarder when the retarder is turned on, directing fluid from a main pump by way of a torque converter to the retarder when the retarder is on, but not filled. When the retarder is off or is on and filled, the method includes directing fluid from the main pump by way of the torque converter to at least one of a lube operation, the tank or a cooler.

Abstract: A method of operating a hydraulic retarder including directing fluid from a retarder pump to the retarder when the retarder is turned on. Fluid from a main pump is directed to a torque converter, which fluid is directed to at least one of a lube operation, a tank or a cooler when the retarder is turned off. Fluid from the main pump by way of the torque converter is directed to the retarder when the retarder is on, but not filled, and to the tank or the lube operation when the retarder is filled.

Abstract: A method of operating a hydraulic retarder includes directing fluid from a retarder pump to the retarder when the retarder is turned on, directing fluid from a main pump by way of a torque converter to the retarder when the retarder is on, but not filled. When the retarder is off or is on and filled, the method includes directing fluid from the main pump by way of the torque converter to at least one of a lube operation, the tank or a cooler.

Abstract: A method of operating a hydraulic retarder including directing fluid from a retarder pump to the retarder when the retarder is turned on. Fluid from a main pump is directed to a torque converter, which fluid is directed to at least one of a lube operation, a tank or a cooler when the retarder is turned off. Fluid from the main pump by way of the torque converter is directed to the retarder when the retarder is on, but not filled, and to the tank or the lube operation when the retarder is filled.

Abstract: A seal carrier that is used to transmit hydraulic fluid to control pistons in a transmission includes a center passage and connecting passages to one or more oil passages. As the seal carrier rotates during operation, the seal carrier acts as a centrifuge and entrapped air in the hydraulic fluid is separated from the hydraulic fluid. The released air moves into the center passage and out through one of the connecting passages, ultimately to a tank or reservoir. A poppet valve in the hydraulic fluid drain rail maintains a positive pressure on the hydraulic fluid at all times to create a pressure differential between the central passage and the tank.

Abstract: A fluid control valve capable of rapidly opening and closing. The valve includes a housing with an annular-shaped spool cavity that contains an annular-shaped spool capable of axial movement within the spool cavity between first and second spool positions. The spool has axially-spaced circumferential spool sealing features and optionally radial passages therethrough. The housing has axially-spaced circumferential housing sealing features configured and disposed within the spool cavity so that, with the spool in the first spool position, fluid flow is enabled through the spool cavity axially between the spool sealing features and the housing sealing features, which provide axial force balancing of the spool. With the spool in the second spool position, the spool sealing features and the housing sealing features cooperate to substantially prevent fluid flow through the spool cavity.