Abstract: A method for controlling wheel hop at a vehicle axle includes determining that one of a difference between average front and rear wheel speeds exceeds a reference difference, a frequency of a signal produced by an accelerometer mounted on the axle exceeds a reference frequency, and a frequency of a lock ring torque exceeds a second reference frequency; pulsing pressure in the wheel brakes of the axle; and reducing engine torque.

Abstract: A locking differential includes a dog clutch configured to selectively couple a carrier to an axle shaft in response to magnetic forces generated by electrical current in a coil. A method of operating the differential is adapted to avoid failed engagement attempts that could potentially damage the dog clutch. If a driver commands engagement of the locking feature while a differential speed, a controller waits to command engagement of the dog clutch until the differential speed decreases below a threshold. The controller measures or infers a temperature of the differential fluid and adjusts the threshold to higher values when the temperature is cold.

Abstract: A locking differential includes a dog clutch configured to selectively couple a carrier to an axle shaft in response to magnetic forces generated by electrical current in a coil. A method of operating the differential is adapted to avoid failed engagement attempts that could potentially damage the dog clutch. If a driver commands engagement of the locking feature while a differential speed, a controller waits to command engagement of the dog clutch until the differential speed decreases below a threshold. The controller measures or infers a temperature of the differential fluid and adjusts the threshold to higher values when the temperature is cold.

Abstract: A sensed element is disclosed for incorporation into an apparatus that includes a rotatable shaft. The sensed element includes a base portion mounted directly on the shaft so as to rotate with the shaft, at least one sensor-detectible feature coupled to the base portion, for use in measuring a rotational speed of the shaft, and a projection extending from the base portion and engageable with a portion of the apparatus other than the shaft to limit movement of the element along the shaft.

Abstract: A method for controlling wheel hop at a vehicle axle includes determining that one of a difference between average front and rear wheel speeds exceeds a reference difference, a frequency of a signal produced by an accelerometer mounted on the axle exceeds a reference frequency, and a frequency of a lock ring torque exceeds a second reference frequency; pulsing pressure in the wheel brakes of the axle; and reducing engine torque.

Abstract: A sensed element is disclosed for incorporation into an apparatus that includes a rotatable shaft. The sensed element includes a base portion mounted directly on the shaft so as to rotate with the shaft, at least one sensor-detectible feature coupled to the base portion, for use in measuring a rotational speed of the shaft, and a projection extending from the base portion and engageable with a portion of the apparatus other than the shaft to limit movement of the element along the shaft.

Abstract: A sensed element is disclosed for incorporation into an apparatus that includes a rotatable shaft. The sensed element includes at least one sensor-detectible feature detectible by a sensing device for use in measuring a rotational speed of the shaft, a base portion coupled to the shaft so as to rotate with the shaft, and a projection extending from the base portion. The projection is engageable with a portion of the apparatus to limit movement of the sensed element along the shaft. The projection may also aid in positioning the sensed element within the apparatus during installation and removal of the sensed element.

Abstract: A method for controlling a locking differential includes determining a temperature-dependent reference voltage at which a coil locks the differentia, determining an electric potential of a battery, using the battery to energize the coil and lock the differential, if the electric potential is equal to or greater than the reference voltage for a current temperature, and maintaining the differential unlocked, if the electric potential is less than the reference voltage.

Abstract: A method for controlling a locking differential for a vehicle includes using a coil to unlock the differential, if the vehicle stops for a period whose length is equal to or greater than a reference length, and using the coil to lock the differential, if the vehicle is moving or stopped for less than the reference length.

Abstract: A sensed element is disclosed for incorporation into an apparatus that includes a rotatable shaft. The sensed element includes at least one sensor-detectible feature detectible by a sensing device for use in measuring a rotational speed of the shaft, a base portion coupled to the shaft so as to rotate with the shaft, and a projection extending from the base portion. The projection is engageable with a portion of the apparatus to limit movement of the sensed element along the shaft. The projection may also aid in positioning the sensed element within the apparatus during installation and removal of the sensed element.

Abstract: A method for controlling a locking differential for a vehicle includes using a coil to unlock the differential, if the vehicle stops for a period whose length is equal to or greater than a reference length, and using the coil to lock the differential, if the vehicle is moving or stopped for less than the reference length.

Abstract: A method for controlling a locking differential includes determining a temperature-dependent reference voltage at which a coil locks the differentia, determining an electric potential of a battery, using the battery to energize the coil and lock the differential, if the electric potential is equal to or greater than the reference voltage for a current temperature, and maintaining the differential unlocked, if the electric potential is less than the reference voltage.

Abstract: A motor vehicle driveline that can transmit power in a 4×4 mode includes two front wheels, a rear drive shaft, a differential mechanism for transmitting power to two rear axle shafts connected driveably through the differential to the rear driveshaft, and a clutch for engaging and disengaging a drive connection in the differential mechanism. A method for controlling operation of the clutch includes the steps of operating the driveline in 4×4 mode, determining a current accelerator pedal position, determining whether a current accelerator pedal position is less than a reference position for a predetermined period, determining a current speed of each front wheel of the vehicle, determining whether a current speed difference between the front wheels of the vehicle is less than a reference wheel slip for a first predetermined period, determining during a second predetermined period whether a current time rate of speed change of the rear drive shaft is less than a reference rear wheel slip.

Abstract: A motor vehicle driveline that can transmits power in a 4×4 mode includes two front wheels, a rear drive shaft, a differential mechanism for transmitting power to two rear axle shafts connected driveably through the differential to the rear driveshaft, and a clutch for engaging and disengaging a drive connection in the differential mechanism. A method for controlling operation of the clutch includes the steps of operating the driveline in 4×4 mode, determining a current accelerator pedal position, determining whether a current accelerator pedal position is less than a reference position for a predetermined period, determining a current speed of each front wheel of the vehicle, determining whether a current speed difference between the front wheels of the vehicle is less than a reference wheel slip for a first predetermined period, determining during a second predetermined period whether a current time rate of speed change of the rear drive shaft is less than a reference rear wheel slip.