This work presents the main observations obtained from the study of several path loss models in the context of vehicular communications that employ frequency bands of TV White Spaces. We have simulated vehicular communications in different urban and suburban scenarios in order to compare the magnitude of the losses exhibited by the following models: Okumura-Hata, COST-Walfisch-Ikegami, Xia-Bertoni, WINNER+, and ITM (Longley-Rice), for both V2I and V2V interactions. Results show important differences between these models and demonstrate the need for a standard model for vehicular communications employing TV frequency bands.