In Va. a four door explorer has a gross vehicle weight above 5000-pounds (light truck). That allow you the 28-inch bumper/frame height.
If you had a two door, then it would be the 23-inch height (passenger vehicle). I have a two door and once got stopped by a cop. We had a discussion about the lift laws. He also said that I could reregister to the higher vehicle weight and be legal with my Explorer.