Can brake discs make intermittant vibrations when/when not braking? What about wheel hubs?

My car has an intermittant vibration that's actually worse coasting downhill (presumably when the front wheels are more heavily loaded).

This has been thru several sets of Michelin MXV4 & Pilot, Yoko, and now Nokian tires. Dynamic balance, weights on both sides at several shops, GSP9700 doesn't eliminate it and roadforce have been good. Rims are MB factory original, tires are stock 195/65 R15. Struts, control arms, ball joints, tie rods, idler, bearings are all in good working order, no excessive play when pulling and pushing 12-6, 3-9, etc....

Car did benefit once or twice from on the car balancing about 9 months ago so I suspect something is out. No visual problems with disc or hub though. Vibration noticable past 60 MPH and have not noticed 'driving thru it'.

Anybody solve this problem by changing discs or hubs?

-brian

__________________
Brian Toscano