A transmission control system includes a first gear engagement element that receives fluid and engages a first gear. An electromagnetic actuator selectively interrupts fluid flow to the first gear engagement element based on a duty cycle of a control signal. A control module adjusts the duty cycle so that a fluid flow rate continuously decreases as the first gear engagement element produces a first torque sufficient to hold the first gear. The flow rate is based on a first estimated volume of the fluid necessary for the first gear engagement element to produce the first torque. The control module computes a current volume of the fluid when the first gear engagement element produces the first torque. The control module adjusts a value of the first estimated volume for subsequent transmission control when a difference between the current volume and the first estimated volume is greater than a predetermined volume.