what is the difference?

 

http://www.dodge.com/model-compare/d...Code=CUD201611

 

I assume you are looking at a pre-owned vehicle since the Crew has not been produced in years. I just traded my Crew, which was had the upgraded audio, Navigation, power lift gate, Hemi, dual zone CC, Towing package, and a few more options. Some of the noted features that the Citadel had during hose years were factory 20" wheels, leather, lighting package (projectors/HID's). I think they did a terrible job at making the Citadel standout between 2011 and 2013. They looked very similar with the exception of the headlights, and in many cases the Crew was ordered with the factory 20's.

 

You could option a crew to be nearly Citadel level. So you really need to look at the individual vehicles and what options are on them. Citadel will have some chrome trim (door handles, mirrors, grille) that will make them stand out.

I used to have a loaded 2012 crew that I liked except I regretted getting the V6, so I traded it for a 2015 RT.

In case you are not aware, starting in 2014 there was a new transmission which was a vast improvement (in my opinion) over the earlier model.