OK, I've had my 70-200 f4 for over a year now (bought new) and the IS is very noticable when it is working. I guess you could call it a grinding noise. I thought it was normal. I just bought a 70-200 IS II f2.8 when they went on sale b/f xmas. The IS on the new lens is very quiet. I now plan to sell the f4 but I'm worried it may be defective and I certainly don't want to sell a defective lens. Is the noise on the f4 normal?



