Abstract: A control strategy and method for controlling friction element engagement and disengagement time for an automatic transmission when the transmission is operating at cold ambient temperatures. During drive-to-reverse or reverse-to-drive friction element engagements with power on, the strategy compensates for a tendency of an oncoming friction element to gain capacity before an off-going clutch loses capacity, thereby avoiding a potential friction element tie-up condition when the transmission is operated with intermediate or high levels of engine torque as the friction elements are sequentially engaged and disengaged during cold rock cycling.

Abstract: A control strategy and method for controlling friction element engagement and disengagement time for an automatic transmission when the transmission is operating at cold ambient temperatures. During drive-to-reverse or reverse-to-drive friction element engagements with power on, the strategy compensates for a tendency of an oncoming friction element to gain capacity before an off-going clutch loses capacity, thereby avoiding a potential friction element tie-up condition when the transmission is operated with intermediate or high levels of engine torque as the friction elements are sequentially engaged and disengaged during cold rock cycling.

Abstract: In an automotive transmission, a method for determining whether an upshift should be enabled or disabled determines the predetermined upshift vehicle speed at which the upshift is scheduled to occur with reference to current throttle position and vehicle speed. The method employs the difference between upshift vehicle speed and current vehicle speed, the current vehicle acceleration, an empirically determined upshift vehicle acceleration referenced to current vehicle speed and the speed difference. If the current vehicle acceleration is equal to or greater than upshift vehicle acceleration, the upshift is enabled; otherwise, the scheduled upshift is disabled.

Abstract: A method for determining whether the torque converter bypass clutch of an automotive transmission should be relocked or a relock should be prevented includes maintaining in a delay counter the number of such relocks that occur, continuously determining in a counter decrement timer the length of the period since the last relock occurred, determining the output of a timer for decrementing the count of the delay counter, decrementing the count of the delay counter and clearing the counter decrement timer provided the period of the counter decrement timer is greater than the output of the timer for decrementing the count of the delay counter.