A garage door operator (10) is disclosed to have a front coupling (60, 90) for a threaded screw (30) of the operator (10) and the rotor of the motor (20). The coupling (60, 90) includes a first coupling device (60) that is a unitary coupling member with opposing recesses (68B, 68A) for receiving each of the rotor shaft (26F) and an end portion (74) of the screw (30). The unitary coupling member thereby connects the screw (30) to the motor (20) for torque transmission from the motor. The second coupling device includes a thrust containment device (92) that is supported on the screw (30), and an intermediate assembly (94, 102, 104, 112, 110, 114) disposed between the thrust containment device and an end portion (44) of the guide rail (40) of the door operator. A retainer component (94) of the intermediate assembly restricts expansion of the thrust containment device.