What was found
MLG PIVOT CASTING (FWD TRUNNION FITTING ASSY) ATTACH HARDWARE CONTINUALLY COMES LOOSE ALLOWING CHAFFING BETWEEN CASTING, WING SPAR, ENLARGING ATTACH BOLT HOLES IN CASTING AND SPAR. AFFECTED LT CASTING HAD BEEN PREVIOUSLY REMOVED, INSPECTED AND INSTALLED IAW MM FOR THIS REASON ONLY 100 HRS PRIOR TO THIS REOCCURENCE. CONDITION HAD BEEN NOTED ON RT CASTING AT SAME INSPECTION HAD BEEN CORRECTED BY REPLACING CASTING WITH NEW, REAMING ATTACH HOLES IN CASTING, SPAR (UTILIZING APPROVED DATA) TO ACCEPT BOLTS. NUTPLATES ON THE FWD SIDE OF WING SPAR, NOT ADEQUATE TO ACCEPT STRESSES IMPOSED ON THEM, LEADING FACTOR IN CONTINUAL LOOSENING OF FWD PIVOT CASTING ATTACH HARDWARE.