I've got an 2007 xterra I've noticed that there are two loose flaps of rubber I have not gotten any screws in the rear tire was not like that I am an careful driver I don't hit curbs or anything I'm careful backing up and parking it in the driveway should I trim the lose flaps of rubber or Just leave it be it was going all over the place when I was driving it home last night should I have those old tires replaced?