Heavy commercial road vehicles are less stable in terms of rollover because of their elevated center of gravity (CG). Rollover is a type of accident in which the vehicle rotates excessively about its longitudinal axis. An untripped rollover happens when the centrifugal force acting at the CG is stronger than the cornering force acting at the tires and the vehicle rolls outwards of the turn. The accurate detection of the onset of untripped rollover is a critical step towards its prevention. This study presents a model based rollover index using the lateral Load Transfer Ratio (LTR) for detection of untripped rollover of heavy commercial road vehicles. The corroboration of any rollover detection and prevention strategy with a full-sized vehicle would be costly and potentially dangerous. Hence, this study investigated the development of a scaled vehicle prototype using the Buckingham π theorem, which can be tested extensively for the detection and prevention of rollover during various aggressive maneuvers. The proposed model, detection strategy and scaled prototype would be used to develop and evaluate rollover prevention schemes for heavy commercial road vehicles.