Derek, please excuse me for interrupting your post and add some background information. Both Nikon Europe and Nikon USA have issued a new service advisory, offering free cleaning and free shutter assembly replacement, including shipping cost, on those D600 bodies that are affected by tiny dust spots on their sensors. This free service includes D600 cameras that have expired warranties. Nikon Europe: https://nikoneurope-en.custhelp.com/app/answers/detail/a_id/55647 Nikon USA: http://www.nikonusa.com/en/Service-...ers-of-the-Nikon-D600-Digital-SLR-Camera.html Those service advisories are carefully worded, e.g. the word "oil" never appears on either one of them. Shun Cheung Derek's original post follows: I bought a refurbished D600 last year. It gave me problems with dust and oil from 4000 to 7000 actuations. At 7000 actuations I wet cleaned it and it has been perfect ever since. Is a matter of fact I have had less issues with dust in my D600 than I had with my D200 and D300. Should I send my camera in anyway?