@marlinsfan Are you looking for what size of roof box will fit on a factory rack?

There's a fit guide that Yakima uses that might help with that.
Yakima Infolookup

Looks like for the 2014 you can't use the factory cross-bars as they are too close to the roof: Yakima Infolookup

You'll want to get Yakima cross-bars instead of using the factory ones and you'll be able to use nearly any of their boxes:
Yakima Infolookup

Thule is the same way: If you get their smallest box it uses the most basic hardware (essentially a u-bolt). To get any of their full-size boxes you'll want to do raised rails.

I'd suggest the Wingbar Evos: Thule Wingbar Evo | Thule | USA
and foot pack: Thule Rapid Crossroad Foot Pack | Thule | USA

That combo will have aero bars (quieter) and they extend past the side-rails so you can mount other things on the bars.

Hope that helps.

I prefer Yakima because of the pictures they offer and the support they provide but I've owned both Thule and Yakima. You can also look at Inno and Rhino Rack. I've installed all those brands in the past.