The best course of action is to follow the manufacturer’s recommendations when it comes to maintenance of your roof rack. As a general rule, however, it’s a good idea to regularly inspect the roof rack for signs of wear and tear, discoloration, cracking or points of weakness. It’s best to do this inspection before and after each use. As for cleaning, often a simple wipe down with a damp rag, or travel through a car wash is more than enough to get the job done.