Abstract This paper focuses on the use of Carbon-Reinforced Epoxy based Polymeric Composite Tubes in place of regular AISI 4130 tubes used in manufacturing of the space-frame chassis of a car. The Automobile industry uses basically three types of chassis, viz, Space-frame chassis, Monocoque chassis and Ladder-frame chassis. The Chassis under study is chassis of an All-Terrain Vehicle and all the calculations and results are done with the help of ANSYS . The paper is basically divided into two parts. The first part deals with the variation of the composition of carbon and epoxy in the polymeric composite tubes and finding out the most accurate composition, which could be used to replace the existing material. The Second parts deals with the variation in the dimensions of the cross-sections of the tube and finding the most accurate dimension which could give competition to the existing norms. The major deciding factor taking in consideration was the maximum deflection observed under basic loading conditions. The paper concludes by comparing the weight of both the chassis, one using AISI 4130 tubes and one using Carbon-Reinforced Epoxy based Polymeric Composite Tubes.