How do I stop a leak in my car's roof where the roof rail is attached?

I have a 2009 Toyota Avensis Estate with factory-fit roof rails. After heavy rain, there's a damp patch above the window, towards the rear. I made sure the roof rail was removed, cleaned and refitted, with attention to sealing any obvious areas. However, again after heavy rain, the damp patch is back. I think that the plastic rail, even with the black rubber seal, allows water in and this water is unable to drain away quickly and the level under the rail builds up. Do you have a practical solution for me, please?

Asked on 2 September 2020 by jcgough

Answered by Russell Campbell
Is the leak definitely coming from the roof rail? We'd advise you to get a friend to sit in the car while you hose it down to see if s/he can spot any leaks. If it is coming through the roof rail, it might be worth replacing the rubber gasket which seals the gap between the roof and the rail.
Tags: leaks
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