There are other options:
Wayne County Fairgrounds has a nice RV park:
http://www.waynecountyfairgrounds.net/Camping.htmlSterling State Park has full hookups:
https://www.midnrreservations.com/SterlingStatePark?MapThere are two Oakland County Parks with campgrounds:
http://www.destinationoakland.com/PARKSANDTRAILS/CAMPGROUNDS/ADDISONOAKS/Pages/default.aspxhttp://www.destinationoakland.com/PARKSANDTRAILS/CAMPGROUNDS/GROVELANDOAKS/Pages/default.aspxAlso, be advised that the DAC is right next door to Comerica Park, so if the Tigers are in town you may have to deal with a ballgame, and most are fully sold out.
Good luck!