I'm about to wash and wax Balerion, and since I have the driveway I thought I'd take my roof rack rails off to be extra thorough. This is the horror show I found underneath:









My HHR is a black granite metallic 2011 with less than 9k miles, but I live in an area where the air quality most of the time is "dirt".

It's not hard to take the rails off: use something to pry up low end of each cap (I used a flathead screwdriver wrapped in tape to prevent any scratch mishaps). Once you hear a pop, it'll come off. Then there are two bolts at each end which have T30 torx heads.

I expect that this grime will take some buffing to completely clean up, but I'll have to live with it just being clean under there for a while. I have temporarily put some panel fasteners in the mount points with silicone for when I wash. when that's all done, the rails will go back on.

Unlike chef () I'm tall enough to see the plugs, so I'll be switching to black rails when I get the chance.

 

In this part of the country you would have found black and green mildew.High humidity and about 65 inches of rain per year does that.
I've taken off various racks and things from different vehicles. Always looks like ---- under there.

 

A thin layer of RTV or maybe some sort of grease ( dielectric ) to keep the area sealed...if RTV only thin coat the very edge so its not impossible to get off in the future..

 

Here's the aftermath: