Vehicles for use in radiation scanning systems to inspect objects are disclosed. In one embodiment, a vehicle has a supporting portion and a radiation source is movably supported by the supporting portion. The source may be moved along the supporting portion to scan an object. The supporting portion may comprise an expandable portion. The vehicle may comprise a truck and an expandable trailer releasably coupled to the truck. The trailer may comprise telescoping rails. In another embodiment, a vehicle with a supporting portion, which may be an expandable portion, movably supports a detector. Vehicles of the first and second embodiments may be driven to an inspection site, where they may be rapidly deployed on opposite sides of an object to be scanned.