Carnac, Thanks for the help on this one.
M931 Truck, tractor, 5-ton, 6 × 6, w/o winch, soft top, ABS
Serial No: C53102830
Registration Number:
NSN 2320012064077 Truck, Tractor: M931A1 - This NSN was on a sticker on the bumper
but this number looks like it should have a winch and closed top...