i know your not going to like this as it means jacking up car again and removing wheels once off smear a a small amount of copper grease around the hub face of the disks (try not to put to much on as it can act as a releasing agent) and using a wire brush remove any oxidation (white powder) from inside wheel hub. get this everyday at work its a comon fault with vw, audi etc the hub, wheel and wheel nuts always suffer from oxidation (different metals). also put an even smaller amount on the 1st few treads of each wheel nut just to stop them seizin. hope this helps prevent future headaches
