2-C+C-2
"2-C+C-2" means there are two sets of articulated axles under the unit. Within each of these sets, there is a truck with two idler axles, and inboard of it are three powered axles. Two of these articulated sets are placed back to back and connected by a hinge. The GG1 electric locomotives were notable examples of this arrangement.
Read more about this topic: AAR Wheel Arrangement