A method for establishing a connection for platooning with Cooperative Adaptive Cruise Control, CACC, with vehicle-to-vehicle, V2V, communication, the method comprising - a subject vehicle determining (S2), by means of a length determination procedure, an assumed length (Las) of a communicating vehicle travelling ahead of the subject vehicle, - if length information about the length (L1) of the communicating vehicle is available (S3) to the subject vehicle, the length information being obtained in a way that is different from said length determination procedure, the subject vehicle comparing (S4) the assumed length with the length according to the length information, and connecting (S5) for platooning to the communicating vehicle if the assumed length (Las) differs from the length (L1) according to the length information by less than a difference threshold value, wherein, if (S4) the assumed length (Las) differs from the length (L1) according to the length information by more than the difference threshold value or if (S3) the length information is not available to the subject vehicle, performing (S6) a target identification procedure to determine whether the vehicle in front of the subject vehicle is the communicating vehicle, the target identification procedure comprises the subject vehicle requesting with the V2V communication that the communicating vehicle performs an action, and determining that the vehicle in front is the communicating vehicle if the subject vehicle detects that the vehicle in front performs the action and, if (S7) it is determined by the performed target identification procedure that the vehicle in front of the subject vehicle is the communicating vehicle, the assumed length (Las) being stored (S10) in a database so that accurate information of the length of the communicating vehicle is saved for future purposes, thereby facilitating future platoon connection procedures. - a subject vehicle determining (S2), by means of a length determination procedure, an assumed length (Las) of a communicating vehicle travelling ahead of the subject vehicle, - if length information about the length (L1) of the communicating vehicle is available (S3) to the subject vehicle, the length information being obtained in a way that is different from said length determination procedure, the subject vehicle comparing (S4) the assumed length with the length according to the length information, and connecting (S5) for platooning to the communicating vehicle if the assumed length (Las) differs from the length (L1) according to the length information by less than a difference threshold value, wherein, if (S4) the assumed length (Las) differs from the length (L1) according to the length information by more than the difference threshold value or if (S3) the length information is not available to the subject vehicle, performing (S6) a target identification procedure to determine whether the vehicle in front of the subject vehicle is the communicating vehicle, the target identification procedure comprises the subject vehicle requesting with the V2V communication that the communicating vehicle performs an action, and determining that the vehicle in front is the communicating vehicle if the subject vehicle detects that the vehicle in front performs the action and, if (S7) it is determined by the performed target identification procedure that the vehicle in front of the subject vehicle is the communicating vehicle, the assumed length (Las) being stored (S10) in a database so that accurate information of the length of the communicating vehicle is saved for future purposes, thereby facilitating future platoon connection procedures. <EOS>