Target tracking refers to the problem of estimating the motion variables of a moving object (target). Road vehicle tracking finds application in various active safety systems used in automobiles such as the Collision Warning System (CWS) and the Collision Avoidance System (CAS). These safety systems typically employ sensors such as Radar, Camera, and/or scanning Lidar to detect and track vehicles in its vicinity. Low-density Flash lidars are relatively new to the commercial market and are seen as a potential alternative to the commonly used Radars and scanning Lidars due to their low cost. However, using these sensors for target tracking is not straightforward due to the low angular resolution of these sensors. In this work, various challenges involved in the use of low-density flash lidars for road vehicle tracking are identified and solutions to these challenges are presented. Further, the efficacy of the developed tracking system will be evaluated for a heavy vehicle Rear-End Collision Avoidance System. This work could potentially help to accelerate the commercialization of CAS by enabling the use of relatively inexpensive low-density flash lidars.