Ford Repair: Taurus grinding/whirring noise

Question
QUESTION: Hi, I just bought a '03 Taurus SEL wagon with 90k miles.  When moving it makes a cyclical whirring/rubbing/grinding noise from somewhere near the front end.  For example, at 60mph this sound cycles over and over, going from louder to softer and then louder again every 2 seconds or so.  I can actually feel the vibration of it through the gas pedal although it is subtle and the sound isn't very loud but it's noticeable.

I would have guessed a front wheel problem (bearings?) but it makes no sense to me how it only cycles once every 2 seconds when the wheels are probably turning 15 times per second.  And I can't think of any other mechanical part that would be moving that slowly at 60mph.

ANSWER: Hi since you seem to believe it's not a wheel bearing as you appear educated , I'd like you to rotate the tires front to back and see if the noise changes and please get back to me.. Thank you

---------- FOLLOW-UP ----------

QUESTION: Well, I'm educated in some things but cars isn't one of them!  I know nothing about wheel bearings except I've heard of them and I've heard they go bad.  It sounds like maybe you think that's what it is?  

Here's another thing.  The seller gave me records including an invoice for 2 new tires from Tires Plus that noted: "Owner declined rack & pinion", which I take to mean that Tires Plus told him he had a r&p problem that he declined to fix.  But does r&p contain anything that would cycle every 2 seconds at 60mph?

Answer
Yea and no, the faster you drive the power steering lowers the reassure via a pressure relief valve in the rack and vice Versace at low speeds . But you would have more of a steering problem. It would feel loose at high speeds and tight at low speeds   so if you rotate the tires and the noise doesn't change , go with a bad wheel bearing .  To determine what side . Drive about 25mph and turn the wheel left or right which ever turn makes the. Ouse get louder . That is the problem side. Other way and more reliable. Jack up both wheels place car in neautral. Grab the spring that is attached to the front strut and spin the wheel . If you have a bad wheel bearing, the noise/ vibration will resonate through the spring you are holding