Creo Direct > Designing in the Creo Direct Environment > Cross Sections > Working With Cross Sections > To Modify Section Dimensions
  
To Modify Section Dimensions
You can change the dimensions of planar cross sections.
Right-click a cross section on the Model Tree and click Edit Section. The Options Toolbar opens and the section dimensions appear. Modify the dimensions as needed (drag the dragger or double-click the dimensions) and middle-click.