rust on wheel drums
 

I Have 2010 s5 bought in December and my wife just notice rust on the wheel drums(where brakes are mounted and the tire mounts to).I have not driven it in last couple of months but was in town yesterday and noticed it. Have not had chance to take car in but will call dealer tomorrow. just wondering if anybody has had this problem.

It could be lack of use, salt adhered from last winter and not properly cleaned, rained on last time it was garaged/parked, no reason to be concerned. Once you drive it again it will disappear.

Wife has been driving it almost daily and has been washed often.

Are you referring to the actual discs for the brakes having rust? If so, it's relatively normal and common for those to rust if the brakes get wet and the car isn't driven for a day ... because it's raw metal. The discs can rust within a hour or two of washing the car if it isn't driven. When I swapped my summer wheels back on my car a couple month ago, I noticed what looked like rust on the coated alloy wheels inside where the centre caps go. It cleaned off though, it wasn't the wheels rusting, but it was a build up of rust particles from the brake discs inside the centre of the wheel. Because it was behind the centre cap, it didn't get cleaned by typical washing. The wheels themselves are painted and clear coated, so I think it would be unusual for them to rust.

Referring to where the wheel mounts.The wheel bolts screw into it. What I would consider the wheel drum.

Those are the wheels hubs :)

Best thing you can do is take it to the dealer and see if the rust/corrosion warranty covers it. Some manufacturers do NOT cover rust on the hubs :(

My s5 had rust on it the day after I bought it lol, called the dealer and they said it was a commom occurence and it would come and go which it has....don't know exactly why, assuming its because of the raw metal like someone else said

It is very common for rust to apppear on the center of the wheel hub. If you have stock Audi wheels you only see it when the wheel is dismounted or if the snap-on wheel bolt covers have been removed. After market wheels typically have a small center "hub cap" that covers this area. What I don't understand is how your wife noticed this - where the wheels off the car at the time? Or are you missing the hub cap?/bolt covers?

If you look inside your rims you will see where the routers are mounted to the steel hubs this is where the rust is.

Yes, that's called the wheel hub which I've already mentioned. Take it to the dealer and see if the hubs are covered by the rust/corrosion warranty. But, don't be surprised if it is not covered. Most manufacturers do not cover it.