In its recent release, the Third Generation Partnership Project (3GPP) has focused on sidelink resource allocation for vehicle-to-everything (V2X) autonomous mode. It assigns Mode 2 for enabling advanced driving applications in the fifth generation (5G) New Radio (NR). In this paper, we analyze the NR-V2X Mode 2 performance. Specifically, the study provides an analytical model for the average packet delivery ratio (PDR) as a function of multiple parameters, such as the number of vehicles and the probability of keeping resources. In addition, the analytical framework is validated by running extensive simulations. Furthermore, we study how altering various parameters impacts the system’s performance to help improve its existing settings.