The transient behaviour of the gear ratio in a 64-ratio transmission was recorded for single ratio-step shifts. The transmission was installed on a test bed and operated at an input torque of 27.1 N·m. at 1500 rpm. It proved to be possible to eliminate shift disturbances entirely by microprocessor control of clutch closure times. Essentially this amounted to delaying the start of clutch closure for fast-acting clutches so that all clutches ceased slipping at the same time.