A vehicle asset and route optimization system and method are provided for enabling vehicle route optimization based on, for example, substitution driver availability, trip cost, and trip schedule and available truck/trailer assets. The optimization system allows for weighing the prioritization factors provided by the various users so as to allocate priority among the most desirable inputs to increase efficiency in the shipping function and in vehicle asset usage and management, particularly in cases of unused excess trailer capacity and the reduction of driver downtime in the entire transportation process.