A hydroformed driveshaft tube, comprising: a first end portion having a substantially cylindrical shape; a second end portion having a substantially cylindrical shape; a first transition portion, a second transition portion and a middle portion, at least a portion of the middle portion having a diameter greater than a diameter of the first end portion and the second end portion; and characterized by: a first constriction portion and a second constriction portion, the middle portion being formed between the first constriction portion and the second constriction portion and being at least partially defined by a circular arc shaped surface of the circular arc shaped surface of revolution corresponding in shape to the first transition portion, the middle portion, and the second transition portion and being formed by rotating a substantially circular arc about an axis of the first end portion and the second end portion, at least a portion of the middle portion having a diameter greater than a diameter of the first end portion and the second end portion, the first transition portion, the middle portion, and the second transition portion having a first concavity; the first transition portion being formed between the first end portion and the first constriction portion; the first constriction portion being defined by a circular arc shaped surface of revolution formed by rotating a substantially circular arc about an axis of the first end portion and the second end portion, and the first constriction portion having a second concavity, the first constriction portion having a diameter greater than the diameter of the first end portion; the second constriction portion being defined by a circular arc shaped surface of revolution formed by rotating a substantially circular arc about an axis of the first end portion and the second end portion, and the second constriction portion having the second concavity, the second constriction having a diameter greater than the diameter of the second end portion; the second transition portion being formed between the second end portion and the second constriction portion; wherein the first concavity is opposite a concavity of the second concavity, the first constriction portion and the second constriction portion each provide a datum to militate against tube buckling which may occur during a hydroforming process used to form the hydroformed driveshaft tube and the middle portion affects a critical speed and a breathing mode frequency of the hydroformed driveshaft tube. a first end portion having a substantially cylindrical shape; a second end portion having a substantially cylindrical shape; a first transition portion, a second transition portion and a middle portion, at least a portion of the middle portion having a diameter greater than a diameter of the first end portion and the second end portion; a first constriction portion and a second constriction portion, the middle portion being formed between the first constriction portion and the second constriction portion and being at least partially defined by a circular arc shaped surface of the circular arc shaped surface of revolution corresponding in shape to the first transition portion, the middle portion, and the second transition portion and being formed by rotating a substantially circular arc about an axis of the first end portion and the second end portion, at least a portion of the middle portion having a diameter greater than a diameter of the first end portion and the second end portion, the first transition portion, the middle portion, and the second transition portion having a first concavity; the first transition portion being formed between the first end portion and the first constriction portion; the first constriction portion being defined by a circular arc shaped surface of revolution formed by rotating a substantially circular arc about an axis of the first end portion and the second end portion, and the first constriction portion having a second concavity, the first constriction portion having a diameter greater than the diameter of the first end portion; the second constriction portion being defined by a circular arc shaped surface of revolution formed by rotating a substantially circular arc about an axis of the first end portion and the second end portion, and the second constriction portion having the second concavity, the second constriction having a diameter greater than the diameter of the second end portion; the second transition portion being formed between the second end portion and the second constriction portion; wherein the first concavity is opposite a concavity of the second concavity, the first constriction portion and the second constriction portion each provide a datum to militate against tube buckling which may occur during a hydroforming process used to form the hydroformed driveshaft tube and the middle portion affects a critical speed and a breathing mode frequency of the hydroformed driveshaft tube.