So I've now got about 4000 mi on the X. ('06 S Auto 4WD). I've noticed that when sitting at a stoplight, the idle resonates the entire vehicle so that it makes a deafening rumble. It's reasonably smooth, but the engine idling in gear vibrates at just the right frequency that it seems to shake the entire truck. It's actually difficult to hear much of anything until you change RPMs (up or down). Is it possible to raise/lower the RPM at idle just a little to fix this?

FWIW, it got it's first oil change at 3700 mi - Mobil 1 synth (5w30), K&N oil filter. I have noticed that despite the anti-drainback valve it clatters on start for a second, just till the oil gets to the lifters, but that's for a different post.