The rear spoiler was attached with only two screws....The airstream generated sufficient "lift" to "pucker" the trunk lid sheet metal (modern vehicles have very thin sheet metal)....This allowed the rear spoiler to rock back-and-forth considerably....At a couple of speed ranges the sail would "resonate" and "oscillate" such that the noise would drive one crazy !!!....Dealer would not fix...Fixed it myself by drilling four 1/4 inch dia. holes, applying some 3M automotive sealant to prevent leakage" and fastening with 4 stainless steel screw, lockwashers and nuts obtained at hardware store.... See more problems this vehicle...