Attach a box scraper to the back of the tractor by connecting the hitch on the grader to the ball on the back of the tractor. A lock will hold the two together and prevent them from disconnecting. Lower the teeth on the box scraper to dig 1 inch below ground level. Follow specific manufacturer's directions. Each box scraper will operate differently.
Drive the tractor across the gravel with the box scraper behind it. This will break up the compacted gravel and allow it to be re-surfaced and releveled.
Remove the box scraper from the back of the tractor, and attach a grader blade in the same manner that the box scraper was attached. Position the grader so it sits level. Some grader blade attachments have a built-in level or automatic leveling system. Follow specific manufacturer's directions for this step.
Drive the tractor across the gravel with the grader blade attached. This will move the loose gravel around, filling in any holes, and smoothing and leveling the entire surface.