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Chevrolet Malibu Maxx Interior and Passenger Comfort Concerns
I've run across loose trim in several Maxxes and it's often because the trim mounted fastener simply wasn't pushed into the metal chassis mount hole underneath the trim.
However if the fastener is missing or damaged then the dealer will have to get involved.
Also, in the Maxx, you may find you get really loud squeaks or buzzes from the hatch trim itself. That's because the hatch trim fasteners squeak against the aluminum the hatch is made of. Only way to fix this (that I know of) is to remove the trim, put heavy fiberglass or other tape over the fasteners (preventing metal-metal contact), and then reassemble the trim to the hatch.