Abstract: A transmission, such as a transmission for a vehicle, a driveline including the transmission, and a method of performing a gear shift using the transmission. The transmission comprises a first transmission shaft, a first gear disposed on the first transmission shaft, a first wet clutch, and a first synchronizer. The first wet clutch and the first synchronizer are configured to selectively drivingly engage the first gear with the first transmission shaft and are connectable in series between the first gear and the first transmission shaft, such that the first gear is drivingly engaged with the first transmission shaft only when both the first wet clutch and the first synchronizer are engaged, and such that the first gear is drivingly disengaged from the first transmission shaft when either one or both of the first wet clutch and the first synchronizer is/are disengaged.

Abstract: Methods and systems for a vehicle transmission are provided. In one example, a vehicle transmission system is provided that includes a first planetary gear set rotationally coupled to a second planetary gear set, a first electrical machine rotationally coupled to a sun gear in the first planetary gear set, and a second electrical machine rotationally coupled to a sun gear in the second planetary gear set. The transmission system also includes an inter-axle differential including a third planetary gear set rotationally coupled to a first axle and a second axle and selectively rotationally coupled to the first planetary gear set and the second planetary gear set, wherein the inter-axle differential is configured to selectively enable and disable speed differentiation between the first and the second axles.

Abstract: A dual-motor transmission therefor, comprising a first and a second electric traction motor, a first gear arrangement, a second gear arrangement, and a summation box. The first gear arrangement includes a shaft and at least a first gear and a second gear, wherein each of the first and the second gears can be selectively engaged and disengaged with the shaft via a clutch, and the first gear arrangement supplies a first torque from the first motor to the summation box. The second gear arrangement includes a shaft and at least a first gear, wherein the first gear can be engaged and disengaged with the shaft via a clutch, and the second gear arrangement supplies a second torque from the second motor to the summation box, and the summation box is configured to combine the first and second torques and to output a combined output torque.

Abstract: Methods and systems for a vehicle transmission are provided. In one example, a vehicle transmission system includes a first planetary gear set rotationally coupled to a second planetary gear set and a first electrical machine rotationally coupled to a gear in the first planetary gear set. The vehicle transmission system further includes a second electrical machine rotationally coupled to a gear in the second planetary gear set and a first clutch configured to selectively disconnect the first and second planetary gear sets from a drive axle.

Abstract: Methods and systems for a vehicle transmission are provided. In one example, a vehicle transmission system is provided that includes a first planetary gear set rotationally coupled to a second planetary gear set, a first electrical machine rotationally coupled to a sun gear in the first planetary gear set, and a second electrical machine rotationally coupled to a sun gear in the second planetary gear set. The transmission system also includes an inter-axle differential including a third planetary gear set rotationally coupled to a first axle and a second axle and selectively rotationally coupled to the first planetary gear set and the second planetary gear set, wherein the inter-axle differential is configured to selectively enable and disable speed differentiation between the first and the second axles.

Abstract: A hydrodynamic retarder system for a vehicle is provided. In a first operational state with the vehicle powered on and a retarder deactivated, a pump directs fluid flow from a fluid sump to a retarder inlet valve in the closed position and directs fluid flow to a second sump. In a second operational state with the vehicle on and the retarder activated, the retarder inlet valve moves to the open position directing fluid flow into a retarder chamber and flowing out of the retarder chamber after filling a second volume and discharging to the second sump.

Abstract: A hydrodynamic retarder system for a vehicle is provided. In a first operational state with the vehicle powered on and a retarder deactivated, a pump directs fluid flow from a fluid sump to a retarder inlet valve in the closed position and directs fluid flow to a second sump. In a second operational state with the vehicle on and the retarder activated, the retarder inlet valve moves to the open position directing fluid flow into a retarder chamber and flowing out of the retarder chamber after filling a second volume and discharging to the second sump.

Abstract: A controllable hydrodynamic retarder system for a transmission including an electronic controller unit (ECU) for selecting and controlling brake torque by adjusting a retarder outlet pressure is described. The system can include an algorithm to calculate a retarder outlet pressure set point or tables or brake torque curves or profiles to allow the ECU to calculate or look up the functional relationships between the retarder RT outlet pressure, a vehicle or rotor speed, and a brake torque curve selected by the operator to provide the selected RT outlet pressure. The systems disclosed can also include a cooling system or utilize a vehicles engine cooling system. In one embodiment, the cooler can be shared between a transmission and the controllable retarder and can be adjusted to accommodate cooling requirements. The ECU can also make adjustments to the RT outlet pressure to address short term and long term RT overheating protection independent of the cooling system.