From the 2004 season onward, all teams which had not finished in the top four in the previous year's Constructors' Championship were allowed to run a third car in the Friday practice session before each Grand Prix, for testing purposes.
A partir da tempada 2004, a todos os equipos que non terminaban entre os catro primeiros do Campionato Mundial de construtores do ano anterior permitíaselles correr cun terceiro coche nos adestramentos libres do venres antes dun Gran Premio para propósitos de proba.