The Skrup at the rear of the Renault Fluence show

Often, the Renault Fluency squeaks on the back doors. To get rid of the unpleasant sound, they need to be greased with silicone grease.

It can also creak the plating (the top edge of the door). In this case, the silicone grease should splash the gap between the door and the plating.

It's possible that the locks are creaking. If so, it is recommended that they be extended and lubricate.