Modification of shifting characteristics based upon shifting direction and drive train load

The exemplary embodiment relates to electronically controlled powershift transmissions for large off-road vehicles. More particularly, the exemplary embodiment relates to a system and a method for shifting the transmission of an agricultural or earth moving vehicle by controlling the engagement of a plurality of clutches in accordance with vehicle loading. An apparatus and method for controlling a plurality of clutches in a powershift transmission. The transmission is coupled to an engine of an off-road vehicle. The method includes receiving a shift command having a shift direction. Clutch timing is selected based on the shift direction. Using the selected shift timing, on-coming clutches are engaged in sequence with disengagement of off-going clutches to achieve smooth shifting.