The presentation type of the member needs to be changed.
Solution: Change the presentation of the member to either 'Standard' or 'Symbolic' so the system line is visible. When selected, there should only be 3 grips visible. In these modes, you can stretch the member. Also note that if using the AutoCAD 'Ortho' mode, the X or Y axis of the UCS must be in the direction you want to stretch the member. | 
