Replays should be available for all cars and all servers.
The only thing is that you can save it once for a race (it records again automatically after every restart) or if it's a cruise server, you can save it only once, and if you want to record again - you have to rejoin the cruise server. You can save replays with the button "2". I've attached an example of the settings menu in which you can change settings to save replays automatically (which is not recommended, because that will cost you a lot of disk space).