New materials are being sought out to replace steel in conventional American vehicles as a way to increase fuel efficiency. Carbon fiber composites are lightweight materials that could replace steel without decreasing strength or safety of a vehicle. These new composites have the possibility of reducing carbon dioxide emissions and increasing overall efficiency of a vehicle throughout its lifetime. Carbon fiber production has the potential to be less carbon intensive than steel production, and it could increase the efficiency of a manufacturing plant due to its compactness and to new technology. Fuel efficiency can be improved by using many techniques to reduce the weight of the car and to improve aerodynamic properties. Increased efficiency leads to less carbon dioxide emissions during the use of the vehicles, which accounts for a huge portion of the carbon dioxide emissions in the United States. Current barriers to implementation of carbon fiber in passenger vehicles include safety and cost. The carbon fiber prototypes were found to be safe in terms of side wind resistance due to its aerodynamic shape and also good in impacts. Carbon fiber is a new technology and still fairly costly, but it definitely has the potential to be cost competitive with steel in the future