Iv got an 2007 s3 with 60,000km , The brakes or wheels rattle or vibrate when i push the brakes at 120-150kph,Is it the brake discs? Is 60k the norm for changing front discs? the car is normal standard s3 no updates,, just bbs wheels, if i need discs im happy with the standard, but can you recommend anything better and cheaper? thanks steve barcelona