VR Lens 'Shifting' on Focus?

I'm new to this camera, got it 3 months ago and love it! Upgraded from a D50. So I drop my D300 w/18-200 VR-DX lens and luckily only shattered the UV-Lens (phew). Lens works fine, but one thing I noticed was a slight click on focus and release - which caused the image to shift about 1-2mm, but every resulting pic was perfect.

At first my Brother (also has same equipment) and I thought it might be the mirror - we swapped lens and same problem with both bodies. Tried a non VR lens and nothing. Soooo, I turned the VR selector off, no clicking, no image shift. Also tried my 70-300 and click/shift with VR on, turn VR off and not click or shift. What the heck?

Will test against my dads 18-200 VR, but does anyone else have this problem or is this normal for VR. I did get the 5 year warranty so could send it in, but why does it only do this with VR on?

Thanks!