Abstract: An automatic powershift vehicle transmission comprising an input shaft; an output shaft; first and second intermediate shafts parallel to the input shaft; a lay shaft parallel to the output shaft; gearing providing first, second, third and fourth forward driving paths from the input shaft to the output shaft; a first clutch and a second clutch between the ends of the input shaft to establish driving connections; a third clutch for establishing the first or third forward driving path when the first clutch is operative; and a fourth clutch for establishing the second or fourth forward driving path when the second clutch is operative.

Abstract: A method of controlling a vehicle transmission, the vehicle transmission including a power shift gearbox, the power shift gearbox having a power shift input shaft, a power shift output shaft, power shift input gearing and power shift output gearing, and a plurality of power shift clutches to drivingly connect the power shift input gearing and the power shift output gearing, and a master clutch operable to connect the power shift input shaft to a prime mover, the method comprising the steps of, disengaging the master clutch, and engaging at least two of the power shift clutches.

Abstract: A method of controlling a vehicle transmission during a gear change thereof, the method comprising operating a plurality of power shift clutches to disengage the power shift input gearing and the power shift output gearing, disengaging the driving connection between the range shift input shaft and the range shift output shaft by means of the range selection gearing, engaging at least two of the power shift clutches to vary the rotational speed of the power shift output shaft and hence the range shift input shaft, and operating the range selection gearing to establish a driving connection between the range shift input shaft and the range shift output shaft.

Abstract: A method of controlling a vehicle transmission, the vehicle transmission including a power shift gearbox, the power shift gearbox having a power shift input shaft, a power shift output shaft, power shift input gearing and power shift output gearing, and a plurality of power shift clutches to drivingly connect the power shift input gearing and the power shift output gearing, and a master clutch operable to connect the power shift input shaft to a prime mover, the method comprising the steps of, disengaging the master clutch, and engaging at least two of the power shift clutches.

Abstract: An automatic powershift vehicle transmission comprising an input shaft; an output shaft; first and second intermediate shafts parallel to the input shaft; a lay shaft parallel to the output shaft; gearing providing first, second, third and fourth forward driving paths from the input shaft to the output shaft; a first clutch and a second clutch between the ends of the input shaft to establish driving connections; a third clutch for establishing the first or third forward driving path when the first clutch is operative; and a fourth clutch for establishing the second or fourth forward driving path when the second clutch is operative.

Abstract: A vehicle of the type described wherein the torque converter has an input shaft adapted to be driven by the engine and connected to an impeller and an output shaft adapted to drive the ground engaging device and connected to a turbine, torque being transmitted between the impeller and the turbine hydro-kinetically by fluid and a reactor member in the fluid path and there being a lock up clutch which, when in an operative condition, connects the torque converter for direct drive without torque conversion between the input shaft and the output shaft and which, when in an inoperative condition, permits drive through the torque converter with torque conversion.

Abstract: A vehicle of the type described wherein the torque converter has an input shaft adapted to be driven by the engine and connected to an impeller and an output shaft adapted to drive the ground engaging means and connected to a turbine, torque being transmitted between the impeller and the turbine hydro-kinetically by fluid and a reactor member in the fluid path and there being a lock up clutch which, when in an operative condition, connects the torque converter for direct drive without torque conversion between the input shaft and the output shaft and which, when in an inoperative condition, pen-nits of drive through the torque converter with torque conversion.