Abstract: A remotely operated hydraulic system is configured to engage an unloader in a semi-trailer. The remotely operated hydraulic system includes a solenoid mechanically coupled to the semi-trailer. The solenoid is further mechanically coupled to at least one air input line and at least one air output line. A receiver is electrically coupled to the solenoid and communicatively coupled to a remote control. The receiver is configured to open and close the solenoid based on a signal from the remote control. An air cylinder is mechanically coupled to the at least one air output line and a manual valve. Receiving air into the air cylinder operates to open the manual valve. A motor is mechanically coupled to the air cylinder and the unloader; wherein hydraulic pressure from the manual valve is configured to turn the motor and thus the unloader.