A transmission includes an input shaft that couples to a prime mover, twin countershafts and a main shaft having gears coupled thereon, an output shaft that selectively provides a torque output to a driveline, a first shift actuator that selectively couples the input shaft to the main shaft. The transmission includes a second shift actuator that couples the main shaft to the output shaft with a selected reduction ratio, and a controller including a vehicle state circuit that interprets at least one vehicle operating condition, and a neutral enforcement circuit that provides a first neutral command to the first shift actuator and a second neutral command to the second shift actuator, in response to the at least one vehicle operating condition indicating that vehicle motion is not intended.

A transmission includes an input shaft that couples to a prime mover, twin countershafts and a main shaft having gears coupled thereon, an output shaft that selectively provides a torque output to a driveline, a first shift actuator that selectively couples the input shaft to the main shaft. The transmission includes a second shift actuator that couples the main shaft to the output shaft with a selected reduction ratio, and a controller including a vehicle state circuit that interprets at least one vehicle operating condition, and a neutral enforcement circuit that provides a first neutral command to the first shift actuator and a second neutral command to the second shift actuator, in response to the at least one vehicle operating condition indicating that vehicle motion is not intended.

A transmission includes an input shaft that couples to a prime mover, twin countershafts and a main shaft having gears coupled thereon, an output shaft that selectively provides a torque output to a driveline, a first shift actuator that selectively couples the input shaft to the main shaft. The transmission includes a second shift actuator that couples the main shaft to the output shaft with a selected reduction ratio, and a controller including a vehicle state circuit that interprets at least one vehicle operating condition, and a neutral enforcement circuit that provides a first neutral command to the first shift actuator and a second neutral command to the second shift actuator, in response to the at least one vehicle operating condition indicating that vehicle motion is not intended.

Systems and methods for performing a garage shift of an automatic transmission of a vehicle comprise maintaining a clutch at a first holding pressure while the transmission is in a neutral gear and a brake input signal satisfies a threshold and maintaining the clutch at a lower second holding pressure while the transmission is in the neutral gear and the brake input signal satisfies the threshold to mitigate or eliminate causing drive torque to be transferred from a torque generating system of the vehicle to its driveline via the transmission. When the brake input signal satisfies the threshold and a shift from the neutral gear to a non-neutral gear is requested, the garage shift is then executed.

Systems and methods for performing a garage shift of an automatic transmission of a vehicle comprise maintaining a clutch at a first holding pressure while the transmission is in a neutral gear and a brake input signal satisfies a threshold and maintaining the clutch at a lower second holding pressure while the transmission is in the neutral gear and the brake input signal satisfies the threshold to mitigate or eliminate causing drive torque to be transferred from a torque generating system of the vehicle to its driveline via the transmission. When the brake input signal satisfies the threshold and a shift from the neutral gear to a non-neutral gear is requested, the garage shift is then executed.

Disclosed is a method for controlling a neutral gear of an automatic transmission. The method includes: when a neutral gear control function of the automatic transmission is in an activated state, an automatic Transmission Control Unit (TCU) collects information on a pressure of a brake main cylinder, a state of a brake pedal, and whether an autohold function is in an activated state or not; and when the pressure of the brake main cylinder is smaller than a pressure threshold P.sub.3 of the neutral gear control function and the autohold function is in an inactivated state, or when the brake pedal is in an unstamped state and the autohold function is in the inactivated state, the automatic TCU controls the neutral gear control function to exit from the activated state.

A method for maintaining idle noise refinement in a vehicle is provided. The method may include performing a D-range neutral control, wherein a controller is configured to apply auto hold threshold values to conditions for entering an auto hold control in a neutral control state, and wherein the auto hold threshold values are determinant of an entry into the D-range neutral control such that the auto hold threshold values limit the conditions for entering the auto hold control.

A transmission includes an input shaft that couples to a prime mover, twin countershafts and a main shaft having gears coupled thereon, an output shaft that selectively provides a torque output to a driveline, a first shift actuator that selectively couples the input shaft to the main shaft. The transmission includes a second shift actuator that couples the main shaft to the output shaft with a selected reduction ratio, and a controller including a vehicle state circuit that interprets at least one vehicle operating condition, and a neutral enforcement circuit that provides a first neutral command to the first shift actuator and a second neutral command to the second shift actuator, in response to the at least one vehicle operating condition indicating that vehicle motion is not intended.

Methods and systems for improving vacuum generation for an engine that may be operated at higher altitudes are presented. In one non-limiting example, a transmission that is mechanically coupled to the engine may be shifted from a gear to neutral in response to an actual total number of times a vehicle brake pedal is applied and partially released while the vehicle is stopped and the brake pedal is applied.

In a case where a predetermined switching operation to a state in which a traveling position is selected from a state in which another shift position of a mechanical transmission device is selected is performed by a driver, a quick engagement command to quickly engage a predetermined engagement device is performed in a state in which output of a predetermined torque is stopped, and then a rapid garage control of increasing a rotation speed of an electric motor at a rotation speed equal to or higher than a predetermined rotation speed is executed. The rapid garage control is executed in a case where a predetermined start condition is established.