A linear actuator comprises a motor having an output. An end block is connected to a casing and to the motor and has a counterbore at a distal end with a bearing seated and retained in the counterbore. A coupling assembly couples the output shaft of the motor to a threaded shaft for transmission of the rotational output to the threaded shaft. A sliding tube is in sliding arrangement with the inner cavity of the casing for moving in translation relative to the casing.