An extensive study of the dynamic performance of multitrailer vehicles, and the influence of double-drawbar dollies (C-dollies) on that performance is reported. Six vehicle configurations (five double-trailer combinations and one triple) are considered. The performance of the six vehicles is examined using a matrix of seven different converter dollies (an A-dolly and 6 C-dollies) and 15 different vehicle parametric variations (e.g., center-of-gravity, height, tire-cornering stiffness, roll stiffness, etc.). The performance quality of the vehicles is judged using measures such as rearward amplification, yaw-damping ratio, static rollover stability, offtracking, and dynamic-load-transfer ratio. The results from over 2800 computer simulation runs are used in a statistical regression analysis to produce simple methods for predicting performance numerics for A-trains based on vehicle parameters easily obtained in the field. Performance improvement factors for C-dollies are also developed. Recommendations for minimum performance standards and for C-dolly specifications are also reported. An economic analysis comparing A-dollies and C-dollies is presented. This analysis is based on data from a field survey and the literature and includes purchase, start-up, operational, and accident cost considerations. This volume, Volume III, is a Technical Summary. Volume I contains the Final Technical Report. Volume II contains Appendices A through H.