Abstract: A system and method for regulating torque transmitted via a torque converter can include providing a lock up clutch between a crankshaft and transmission of a vehicle. A position sensor can output data indicative of at least one of an engaged position of the lock-up clutch, a transitional position of the lock-up clutch, and a disengaged position of the lock-up clutch. An engine speed sensor can output data indicative of rotational speed of the crankshaft. A controller can be placed in electrical communication with the engine speed sensor and the position sensor and configured to determine when actuation of the lock-up clutch is desired. The controller can be configured to determine a torque reduction target based on certain variables, for example, engine acceleration. The controller can then signal the engine to output torque substantially equal to the torque reduction target when conditions exist that warrant torque reduction.

Abstract: An apparatus and method for automatically controlling a drivetrain coupled to at least one drive wheel of a vehicle can include providing a first assembly including a low range drive ratio and a high range drive ratio. An electronic control unit can be configured to receive information from at least one sensor located on the vehicle and to provide an output signal based on the information. An actuator mechanism can be provided and configured to cause the first assembly to operate at a selected one of the low range drive ratio and the high range drive ratio based on instructions from the control unit. Separate algorithms can be provided to determine when to actuate from the high range drive ratio to the low range drive ratio and vice versa.

Abstract: A vehicle drivetrain can include various structures, such as a multi-ratio transmission, a two-speed final drive assembly connected in series with the multi-ratio transmission and including a low speed final drive ratio and a high speed final drive ratio, a pair of front driveshafts driven by the two-speed final drive assembly, a pair of rear driveshafts, a rear differential assembly connected to the two-speed final drive assembly, and a control assembly including. The control assembly can include a controller in electrical communication with portions of the rear differential assembly, such as a variable displacement pump and purge valve. An input array can be in electrical communication with the controller and can include a plurality of sensors, and at least one switch accessible to an operator of the vehicle. Various related methods can also be executed for control and operation of such a drivetrain.

Abstract: A system and method for regulating torque transmitted via a torque converter can include providing a lock up clutch between a crankshaft and transmission of a vehicle. A position sensor can output data indicative of at least one of an engaged position of the lock-up clutch, a transitional position of the lock-up clutch, and a disengaged position of the lock-up clutch. An engine speed sensor can output data indicative of rotational speed of the crankshaft. A controller can be placed in electrical communication with the engine speed sensor and the position sensor and configured to determine when actuation of the lock-up clutch is desired. The controller can be configured to determine a torque reduction target based on certain variables, for example, engine acceleration. The controller can then signal the engine to output torque substantially equal to the torque reduction target when conditions exist that warrant torque reduction.

Abstract: A vehicle anti-rollback system and method can be incorporated into a vehicle that includes a pair of front wheels, a pair of rear wheels, a power unit, and a transmission connecting the power unit to at least one wheel of the front and rear wheels. The transmission can include a plurality of forward drive ratios and at least one reverse drive ratio and a two speed final drive ratio transmission configured to select between a high range drive ratio and a low range drive ratio when the transmission is in one of the plurality of forward drive ratios. A controller can be provided that senses a vehicle rollback condition. When the rollback condition is detected, the controller can decrease torque distributed from the power unit of the vehicle to the at least one wheel, and can actuate a brake. While the vehicle is braked and torque transfer is reduced, the controller can execute drive ratio changeover in a stable manner from the high range drive ratio to the low range drive ratio.

Abstract: A vehicle anti-rollback system and method can be incorporated into a vehicle that includes a pair of front wheels, a pair of rear wheels, a power unit, and a transmission connecting the power unit to at least one wheel of the front and rear wheels. The transmission can include a plurality of forward drive ratios and at least one reverse drive ratio and a two speed final drive ratio transmission configured to select between a high range drive ratio and a low range drive ratio when the transmission is in one of the plurality of forward drive ratios. A controller can be provided that senses a vehicle rollback condition. When the rollback condition is detected, the controller can decrease torque distributed from the power unit of the vehicle to the at least one wheel, and can actuate a brake. While the vehicle is braked and torque transfer is reduced, the controller can execute drive ratio changeover in a stable manner from the high range drive ratio to the low range drive ratio.

Abstract: A vehicle drivetrain can include various structures, such as a multi-ratio transmission, a two-speed final drive assembly connected in series with the multi-ratio transmission and including a low speed final drive ratio and a high speed final drive ratio, a pair of front driveshafts driven by the two-speed final drive assembly, a pair of rear driveshafts, a rear differential assembly connected to the two-speed final drive assembly, and a control assembly including. The control assembly can include a controller in electrical communication with portions of the rear differential assembly, such as a variable displacement pump and purge valve. An input array can be in electrical communication with the controller and can include a plurality of sensors, and at least one switch accessible to an operator of the vehicle. Various related methods can also be executed for control and operation of such a drivetrain.

Abstract: An apparatus and method for automatically controlling a drivetrain coupled to at least one drive wheel of a vehicle can include providing a first assembly including a low range drive ratio and a high range drive ratio. An electronic control unit can be configured to receive information from at least one sensor located on the vehicle and to provide an output signal based on the information. An actuator mechanism can be provided and configured to cause the first assembly to operate at a selected one of the low range drive ratio and the high range drive ratio based on instructions from the control unit. Separate algorithms can be provided to determine when to actuate from the high range drive ratio to the low range drive ratio and vice versa.

Abstract: A lock-up clutch control method and apparatus controls a lock-up state of a torque converter interposed between a drive unit and a transmission on a vehicle. Data indicative of the operating condition of an antilock braking system can be provided as input to the control method and apparatus and affect the lock-up state of the torque converter.

Abstract: A lock-up clutch control method and apparatus controls a lock-up state of a torque converter interposed between a drive unit and a transmission on a vehicle. Data indicative of the operating condition of an antilock braking system can be provided as input to the control method and apparatus and affect the lock-up state of the torque converter.