Go to the Meeman-Shelby Forest State Park CG instead. Much nicer. Much safer. If you are going to Graceland, it will be about a 45 minute drive.
http://www.tn.gov/environment/parks/MeemanShelby/An alternative, closer to downtown is the Tom Sawyer CG across the Mississippi River in West Memphis, AR. Not nearly as nice as Shelby Forest though.
http://tomsawyerrvpark.com/A third option is the Agricenter International CG. It is about the same distance from Graceland as Tom Sawyer, but is not as nice a CG.
http://www.agricenter.org/rvpark.htmlBobbo (Memphis native)
The Graceland area is definitely an "avoid after dark" area.