Abstract: A work vehicle adapted to be towed from one job site to the next at highway speeds, and then converted upon reaching a job site to be self-propelling. The towable work vehicle includes lift arms with an attachment system allowing for ready attachment to, and detachment from, a variety of materials handling attachments that are used to perform diverse tasks at the job site. Tow arms attachable to the towing vehicle may be swept forward when not in use to a position underneath the vehicle so as to not interfere with work operations at the job site. A ballast system in one form uses movable weights to allow redistribution of weight on the vehicle to convert the vehicle between towing and operational modes, and in another form uses a fluid fillable tank to allow ballast to be added for use of the vehicle on a job site.