I previously owned a 2011 RTS and now own a 2014 RT Limited. I have noticed that the 2014 gets very dirty in the rear pretty quick as well as at the bottom of the front fenders. The 2011 didn't seem to get this dirty. It seems the aerodynamics have changed some causing an updraft in the rear??????? Has anyone installed the rear mud flap on a 2014 RT and does it help keep the rear clean????