What was found
IN THE CLIMB OUT RIGHT ENGINE VIB INCREASE TO 3.8 AT LEVEL OFF AT FL380 DECREASED BACK TO .6 A/ RETURNED TO FIELD (ATB) AND LANDED MTX GROUNDED A/C AND PERFORMED GENERAL VISUAL INSPECTION ON FAN BLADES, EXAHUST NO EVIDENCE OF DAMAGED. FOUND RIGHT CORE COWL ROD CHAFING AGAINST TURBINE COOLING MANIFOLD. REMOVED ROD AND PERFORMED ENGINE VIBRATION SURVEY REF AMM 71-00-00 DURING HIGH POWER RUN FOUND FAN VIBRATION STABLE AT 1.3 TO 1.4 NO DEFECT FOUND. A/C OK TO CONTINUE. A/C REMAINS NO ETOPS. MTX RETURNED A/C TO SERVICE.