@Silverracer I'm having that problem. I have no idea how to correct it but I keep getting a message in red after the synchronization failure it'll say OOS-CAR or JOOS-CAR I'm not sure which. Would it have anything to do with modifying the file for the XRGT? I swapped some files to make it look like a Mustang and it worked online for some time but then when I updated the game to 6B it stopped letting me online. I've even tried using my other non modified cars and they won't work either.