Okay, thanks, that is very helpful.
So just so that I'm clear... the driveshaft issue only affects 1st > 2nd, and no other gear? Is this anything that I can count on Ford to fix under warranty, with some prodding, or do they simply consider this "normal behavior?"
The drievshaft would contribute to it in all gears, but you may only hear it at certain points. Before you go buy a driveshaft I would have the dealer check it out and also look yourself at all the bushings, etc to make sure it isn't there.