Document 6rJBLrk7wLDrNGwDGJYNL41

BRAKE SYSTEM SERVICE DISC BRAKE ROTOR INSPECTION (continued) LESSON ONE-MODULE 2 Hern Description 1 Cleaning Hub Item Description 2 Cleaning Rotor Whenever a "top hat" style rotor is removed from a vehicle, rust will become dislodged at the rotor-to-hub mating surfaces. This rust (if not removed) will create additional runout at the rotor surface when the rotor is reinstalled on the vehicle. NOTE: To prevent this rust from causing excessive runout, the mating surfaces between the rotor and wheel hub must be thoroughly cleaned prior to rotor installation. Failure to clean these surfaces will likely cause brake shudder concerns and/or other concerns that are associated with excessive rotor runout (vibration, pedal pulsa tions, etc.) Before removing a "top hat" style rotor, always mark the rotor's position in relation to a wheel stud, to ensure correct rotor position during reinstallation. If the rotor is difficult to remove due to wheel hub rust, spray penetrat ing oil at the studs against the outer rotor hat. If this action fails to loosen the rotor, apply heat sparingly around and between the stud areas. Do not use temperatures higher than those that are generated by a propane torch. Heat levels that are generated by an oxyacetylene torch will cause damage to wheel bearings. NEVER strike the rotor from either braking surface. Brake System Diagnosis and Repair September, 2005 39