It's a little tricky to find. I'd park at the Githens Middle School parking lot, 4800 Old Chapel Hill Rd, Durham,
NC 27707. From here, walk east past the athletic field and into the woods. Continue east bushwhacking through the woods to the powerline. Continue east to a branch of New Hope Creek. Cross where you can to get to the large island in the creek. Continue east to the east side of the island, then head north along the creek until you find the tree. Simple. I would do this only on a Sunday during deer gun season. I have pics of the champion here:
Carya laciniosa. It's a fun area to explore even if you don't find the tree. Good luck!