As I've visited various centers across the southeast, from RCH to ATL, from CRW to SAV, from WMN to KNX, and everywhere in between there seems to be a common denominator with these new straight trucks, and no, it's not that they're all Paccar's. Regardless of whether they're 24 foot or even 20 foot trucks, they ALL have air brakes...so wouldn't that mean atleast a Class B CDL be required to operate these vehicles??
Perhaps the non-CDL trucks mentioned are going to big city areas such as Boston, Newark, Chicago, or LA but as for what I've seen it's been nothing but straight trucks with air brakes, regardless of the size box on the back.