Case Clearance
WARNING: This page is about a different car, the 2006 Subaru Outback. However, it is still accessible from the selected car via links, so may be relevant.
Measure the clearance between the outer rotor and rear chain cover rotor housing. If the clearance exceeds the standard value, replace the outer rotor.
Case clearance:
Standard
0.110 - 0.175 mm (0.0043 - 0.0069 in)