Hello DaxFx and welcome to best scooter forum on the web.When I've had this happen to me, I backed off on the mounting bolts and cut some pieces from a 1/16th inch piece of black rubber and slid them up under the rear of the top box and then re tightened the bolts. Worked for me. You might even cut out four ribber washers and place them on all for bolts between the bottom of the box and the mounting surface. Hope this helps.