A Computational Fluid Dynamics (CFD) study was completed to characterize the fuel consumption in terms of the separation distance of a Driver-Assistive-Truck-Platooning (DATP). The DATP system considered utilizes radar and GPS for a redundant range measurement, paired with Vehicle to Vehicle (V2V) communications to enable regulation of the longitudinal distance between the pair of trucks without acceleration input from the rear driver. The linkage of information between the trucks promotes increased safety between the following trucks, while improving their fuel economy. The results from this study are compared to previous works. Preliminary analysis of the system indicated that the fuel economy of both trucks increases dramatically as the separation distance diminishes.Additionally, an SAE Type-II fuel economy test complying with the (1986) SAE J1321 standard was completed to correlate the computational studies. Tests at separation distances of 30ft, 40ft, 50ft, 75ft and 150ft were conducted to examine the predicted trend between vehicle separation and drag reduction. Results from the fuel economy tests indicate that while the overall performance of the platoon monotonically improves as separation distance diminishes, the rear truck exhibits an unanticipated trend. Potential explanations for the rear truck’s trend are also presented, including lateral offset and thermodynamic properties of the engine.