What was found
MEM - DURING APPROACH, SLAT DISAGREEMENT LIGHT ILLUMINATED ON SLAT EXTENSION. A SLIGHT ROLL WAS EXPERIENCED BEFORE BOTH SLATS WERE FULLY EXTENDED. AN UNEVENTFUL LANDING WAS ACCOMPLISHED. LUBED SLAT T-DUCTS, CYCLED SLATS SEVERAL TIMES. OPERATIONAL CHECK OK, AIRCRAFT RETURNED TO SERVICE.