Overspeeding and overloading contribute to road accidents. In developing countries, overloading is often indicated by open boot due to commercial transporters’ motivation to carry an excess load to boost revenue. Therefore, there is a need to provide measures to control or eliminate the practice of overspeeding and overloading. This study aims to conduct a parametric study to determine the effect of vehicle speed and boot opening on the aerodynamics of airflow around a typical minibus, fuel consumption, and CO2 emission, and recommend optimum boot opening. Computational Fluid Dynamics is employed using the FLUENT™ program. Results show the existence of a wavy pattern for drag coefficient, fuel consumption, and CO2 emission concerning boot opening. Furthermore, two boot opening regions exist: and . The first region exhibits low prediction error (maximum of 7.25%) and better fit of regression model to FLUENT™ data. The first region also has lower susceptibility to exhibit handling instability. Therefore, boot opening around is recommended as the optimum boot opening, to ensure minimum fuel consumption and CO2 emissions, improve handling and safety. The developed regression models could inform regulatory bodies’ formulation and implementation of policies to mitigate road accidents. Keywords—Boot Opening, CO2 emission, Fuel Consumption, Pressure drag, Total Drag, Minibus, Viscous Drag