Variator (20) and forward clutch (Fwd/C) disposed in series are provided between engine (1) having starter motor (15) and driving wheel (7). Sailing stop control that, on the basis of satisfaction of sailing entering condition, interrupts power transmission by frictional engagement element (Fwd/C), stops engine (1) and performs coast-travel is performed. When sailing entering condition is satisfied, coast-travel is started with rotation stop timing of variator (20) being delayed with respect to rotation stop timing of engine (1). When accelerator pedal depression operation intervenes after start of coast-travel, engine (1) is restarted by starter motor (15). When judged that input and output rotation speeds of frictional engagement element (Fwd/C) become synchronization rotation speed after restart of engine (1), frictional engagement element (Fwd/C) is reengaged. Shift response from coast-travel to normal travel is therefore improved at change-of-mind at which sailing quitting condition is satisfied during progress of automatic stop of engine.

A method of controlling an axle assembly. The method includes executing a speed synchronization mode and operating a clutch actuator to shift a clutch from a neutral position toward an engaged position. The method may also include executing a low torque synchronization mode when the clutch cannot be shifted from a neutral position to an engaged position within a first predetermined period of time.

A vehicle includes a transmission having a torque converter, an oncoming clutch, and a controller. The controller is programmed to, in response to a torque of the oncoming clutch exceeding an estimated average by a threshold during an engagement, increase the torque of the oncoming clutch via a feedforward command and adjust the torque of the oncoming clutch via a feedback command to compensate for deviations in the torque generated by the feedforward command during the engagement.

A method and a system for controlling a backlash of a powertrain included in a vehicle in connection with a gear shifting operation is presented. The method comprises: controlling, in connection with a first gear shifting operation, a clutch included in the powertrain to a slipping position, in which slipping position the clutch transfers a slipping torque that is less than a torque being transferred in a closed position for the clutch; analyzing a change of a rotational speed for an input shaft of a gearbox included in the powertrain; determining a position for the clutch, for which position the change of the rotational speed has a value corresponding to a backlash torque, the backlash torque having a predetermined value for eliminating the backlash; and utilizing the determined clutch position for controlling the clutch in connection with a second subsequent gear shifting operation.

A method for operating a transmission device for a motor vehicle, wherein the transmission device has an automatic clutch and a manual transmission. During one operation of the transmission device, the clutch is closed before a driving gear is engaged at the manual transmission if, when the clutch is at least partially open, actuation of the manual transmission is identified.

Variator (20) and forward clutch (Fwd/C) disposed in series are provided between engine (1) having starter motor (15) and driving wheel (7). Sailing stop control that, on the basis of satisfaction of sailing entering condition, interrupts power transmission by frictional engagement element (Fwd/C), stops engine (1) and performs coast-travel is performed. When sailing entering condition is satisfied, coast-travel is started with rotation stop timing of variator (20) being delayed with respect to rotation stop timing of engine (1). When accelerator pedal depression operation intervenes after start of coast-travel, engine (1) is restarted by starter motor (15). When judged that input and output rotation speeds of frictional engagement element (Fwd/C) become synchronization rotation speed after restart of engine (1), frictional engagement element (Fwd/C) is reengaged. Shift response from coast-travel to normal travel is therefore improved at change-of-mind at which sailing quitting condition is satisfied during progress of automatic stop of engine.

A vehicle having a clutch which connects an engine with a driveline which includes a multi-ratio gearbox, the clutch having an actuator which can be operated by a vehicle driver to engage and disengage the clutch, the actuator also having a control system arranged to move the clutch between fully engaged and fully released positions through a range of positions allowing variable levels of clutch slip in order to automatically reduce torsional vibrations in the driveline. The control system is configured to recognize a plurality of predetermined Vehicle Operation Modes defined by the combination of a Clutch Slip Status criterion as hereinbefore defined with one or more of the hereinbefore defined operating criteria of Manual Clutch Position Control Input Interface Status, Release Bearing Position Status and Slip Velocity Demand Status and, dependent on the recognized Vehicle Operation Mode, the control system applies a different clutch control strategy to achieve the required level of clutch slip to damp vibration in the driveline and provide transition between the different Vehicle Operation Modes without exciting an uncomfortable level of vibration in the driveline.

A method for operating a vehicle drive-train having a continuously power-branched transmission with secondary coupling. In the open operating condition of reversing clutches of a reversing gear unit, torque applied in the area of a drive output can be supported by a range group in the area of a variator. In the event of a command to interrupt the power flow between a drive engine and the drive output, it is checked whether the vehicle is on an inclined surface and if the result of that inquiry is positive, the power flow between the drive engine and the transmission is interrupted at the latest when the rotational speed of the drive output is reduced to zero by opening the reversing clutches, while the active connection between the drive output and the variator is maintained by way of the range group.

A transmission includes an input shaft and an output shaft, the input shaft selectively accepting a torque input from a prime mover, and the output shaft selectively providing torque output to a driveline. A controller determines a shaft displacement angle representing an angle value of rotational displacement difference between at least two shafts of the transmission, and performs a transmission operation responsive to the shaft displacement angle.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.