I have a loud cabin buzzing at high speeds what could this be? on 2009 Ford F-350 Super Duty

It sounds like it is coming from the driver or passenger door or window area. It only happens at wind speeds greater that 70 MPH, ie 55 MPH vehicle speed with a 20 MPH head wind. It goes away when we get behind a semi. It was intermittent at 20K mile but appears to be constant at high speeds now (29K miles).

by in Phoenix, AZ on May 19, 2013
1 answer
ANSWER by on May 20, 2013
POSS DOOR WINDOW SEAL IS TWISTED OR CRACKED.INSP FOR DEFECTS