Can you ever get rust out of a car part once it is in?

My 2008 Audi A4 S has rust developing around the two front wheel wells and I need to know how to deal with it. Can you ever get rust out of a car part once it is in? – John L.

From my correspondence with John, I know that he had some minor stone chips that turned into surface rust on his front fenders, which he had repaired. Recently, the corrosion has creeped back to the surface.

Many body shops offer a lifetime guarantee on repairs, with the single exception universally excluded being rust. Complete panel replacement is the only repair procedure for owners who need a guarantee. Luckily, most front fenders offer relatively easily replacement when compared to other structural areas such as rear quarter-panels and the roof. Rust appearing on these pieces is repaired using a variety of methods, and every shop has its own preferred techniques – from grinding and sandblasting to cutting out the piece and welding in a repair panel. Results vary with the skill of the individual body technician.