You should be fine using Hellwig's Sway bar with this add-a-leaf kit, since Hellwig's end links have enough adjustment to compensate for this add-a-leaf kit's 1.5" to 2" of lift. Though you may want to hold off the sway bar install until the add-a-leafs are fully broken in and have settled closer to their 1.5" normal ride height so you don't have to readjust the end links later.