The heavy duty hydraulic disconnect allow the tool strings to detach at a predetermined point when the ball seated on the seat. The drop ball locates on the piston sleeve, creating back pressure to shear the pins and disconnect the tool. High torque capabilities are achieved by using positive torque drive teeth between the top sub and main body. This makes the heavy duty disconnect ideally suited for high torque, such as drilling, milling and fishing operation. The piston sleeve inside the tool is pressure balanced, so internal pressure does not affect the hydraulic configuration and shear value.