what shock center or rear? if bottom center is rubbing means u blew out the bolts that hold the mount. rear if u have an ohlin or anu shock with a resivor its cause u dont have 7.5 inch wheels if its a stock shock might be tention or ur upper wheels rubber has delamitated and riped off. befor u start gettin all worried every shock gets rubber a little no matter what skid. the thing that matters is if its enough to rub threw or not. oh another thing ive noticed wich is big with polaris is if the hifax rubs threw to the point of ruining the rails it allso ruins the bottom of the center shock.