Abstract: A system for controlling the engagement and disengagement of one or more clutches that are adapted to operatively connect an engine and an automatic transmission. The system including a control device for determining if a negative torque condition exists and to provide an output or signal to decrease the rotational speed of said engine in response to the determination of the existence of a negative torque condition.

Abstract: Automated calibration of an automatic transmission design generates upshift scheduling curves in a throttle level/transmission output speed plane based upon laboratory-generated data and user generated drivability data. Downshift scheduling curves and torque converter lock-up and unlock curves are then generated as offsets from breakpoints on corresponding upshift curves, the offsets determined principally from the drivability data.

Abstract: A vehicle powertrain has an engine coupled to an electronically-controlled automatic transmission. A method for controlling the vehicle powertrain during a transmission shift from a neutral gear to a drive gear detects a change in a signal indicative of a desired transmission gear change from a neutral gear to a drive gear. An engine idle speed is reduced by a predetermined RPM in response to the change in the signal. The transmission is shifted from the neutral gear into the drive gear upon the engine idle speed being reduced by the predetermined RPM.