Oh man, that looks really terrible. That kind of things are mostly caused by the really terrible detergents and all the other solutions used by the automatic car washes.
Its not the car wash, per se, but instead it is the cheap anodizing on the cross bars. Anodizing creates a very thin layer of porous aluminum oxide which is then dyed using various colors which absorb into the pores and are "sealed" using various methods. Cheap anodizing uses poor quality dye and sealer which results in the color bleeding back out of the parts, especially when soaps and detergents are used. That's why the WD-40 makes them look better temporarily. It fills in the pores until it is washed away again. There is nothing you can do about it except have the bars re-coated somehow. I recommend having them powdercoated at a reputable shop using a UV-rated powder. Cheap powder that is not UV-rated will end up doing essentially the same thing over a short period of time. Line-X or bedliner would also be good options.
I wonder if the lifetime warranty from Prinsu covers defects in the powdercoat finish. I just ordered one of these and hope it holds up better than this seems to be.
This kind of seems like an issue with the racks finish since the rest of the vehicle seems fine.
This was my thought. These bars should be able to take more abuse then my paint.
have you tried rubbing oil on it?
Most likely all made in china.
I wonder if the lifetime warranty from Prinsu covers defects in the powdercoat finish. I just ordered one of these and hope it holds up better than this seems to be.
I may have just missed it, but how old were these bars when they began to discolor? Have they worsened significantly?