PID (Proportional-Integral-Derivative) and MPC (Model Predictive Control) algorithms are used to synthesize the upper-level controller of a vehicle equipped with an ACC (Adaptive Cruise Control) system. Both controllers are analysed, with and without constraints, using a simple vehicle model under critical TM (Transitional Manoeuvres). A comparative analysis of both controllers’ results has been conducted. The comparison gives the suitability of MPC for ACC application over PID controller. The flaws of PID control approach for the given application are highlighted. This approach can be helpful for selecting the suitable controller for the given application