For cars used for racing, Porsche recommends replacing these every 16,800 miles (28,000 km). This is a set, it includes the front wheel carriers (left and right side).
Now don't panic, this service interval is only required for race usage. So to put that in perspective, Sebring International Raceway is 3.7 miles. So that would be about 4540 laps at Sebring!!
For 2009-2012 GT3 models.
