Abstract: A method for controlling the speed of internal combustion engines in heavy duty trucks and the like compensates for the overshoot, i.e., the difference between a targeted or commanded engine speed and a transient overspeed or underspeed. The method comprehends executing a program or subroutine where a throttle or engine speed change command is received by a controller, the engine speed change is monitored, a value of overshoot (on both an engine speed increase or decrease) is detected and the detected overshoot is subsequently utilized to temporarily reduce the speed change command, thereby effectively eliminating the overshoot and more positively and quickly arriving at the targeted engine speed.

Abstract: A method for self configuring automated mechanical transmissions (AMT) and electronic control units (ECU) ensures compatibility therebetween. The method comprehends undertaking a program or subroutine when the vehicle is first powered up which moves the shift operators into a predetermined position. The shift operators include full stroke sensors. Depending upon differences between the commanded shift pattern and the actual shift pattern of the transmission, the specific type of transmission, for example, a twelve speed or a sixteen speed, can be determined.

Abstract: A vehicle power train system includes an engine, a transmission, and a centrifugal clutch assembly that selectively couples an engine output shaft to a transmission input shaft in response to an operator input. An operator selects a desired vehicle-operating mode by actuating a shift lever or shift switch from a gear selection device. The gear selection device indicates many different operating modes and includes a low-speed maneuvering mode that is selected for low-speed operations such as coupling a truck to a trailer, or positioning a truck and/or trailer in relation to a loading dock area. Once the low-speed maneuvering mode is selected, a control unit controls at least one of engine speed and engine torque to indirectly effect clutch slippage, which results in improved vehicle speed control at low-speed operations.

Abstract: A master clutch includes a pressure plate adjacent to a friction disc. A centrifugal weight forces the pressure plate and friction disc into engagement when in a desired install position. A locking device retains the centrifugal weight in the desired installed position. A controller sends an electronic command to a system component, such as an engine, to disengage the locking device. In one example, the electronic command may be an engine speed command that is above an engine speed limit in a normal vehicle operating mode. Commanding the engine to run at a speed greater than the typical engine speed limit moves the centrifugal weight out of the desired installed position making the master clutch operational.

Abstract: A vehicle transmission system includes a transmission component that has an engaged condition where torque can be transferred from a vehicle engine to a drive component, and a non-engaged condition where torque is prohibited from being transferred to the drive component. A controller generates control signals to control whether the transmission component is in the engaged or non-engaged condition. The controller also identifies when a vehicle start maneuver is a coast start based on vehicle conditions existing just prior to or during the vehicle start maneuver. When a coast start is identified, the controller generates a control signal to either disengage the transmission component or to maintain the transmission component in the non-engaged condition until engine speed generally matches transmission component speed. The controller can directly control engagement by automatically actuating a movable transmission member or can indirectly control engagement by controlling engine speed.

Abstract: The inventive transmission has at least two different shift modes for shifting between the same two gear ratios. A control unit electronically senses various vehicle conditions and based on this information selects the appropriate shift mode suited for the particular driving situation. The transmission then shifts from one gear ratio to another based on this selection.

Abstract: The inventive transmission has at least two different shift modes for shifting between the same two gear ratios. A control unit electronically senses various vehicle conditions and based on this information selects the appropriate shift mode suited for the particular driving situation. The transmission then shifts from one gear ratio to another based on this selection.

Abstract: A strategy for overcoming a tooth butt condition includes changing a target closed clutch position over time. When a tooth butt condition exists, a controller selectively closes a clutch to provide limited engagement between the engine and the transmission. A first target closed clutch position is used on the first attempt. If the tooth butt condition is not resolved, the controller then changes the target closed clutch position to provide a different level of engagement between the engine and the transmission. This process is repeated until the tooth butt condition is resolved, a preselected period of time expires, a maximum number of attempts has been completed or the maximum desirable closed clutch position has been used.

Abstract: A strategy for overcoming a tooth butt condition includes changing a target closed clutch position over time. When a tooth butt condition exists, a controller selectively closes a clutch to provide limited engagement between the engine and the transmission. A first target closed clutch position is used on the first attempt. If the tooth butt condition is not resolved, the controller then changes the target closed clutch position to provide a different level of engagement between the engine and the transmission. This process is repeated until the tooth butt condition is resolved, a preselected period of time expires, a maximum number of attempts has been completed or the maximum desirable closed clutch position has been used.