This is a very annoying noise, I know what you people are talking about.
I went down a path to find a cure for this last year and I think I've found some answers on how to repair this problem. If you think the noise is coming from within your jeep and not underneath it, than check out this thread and please let me know what happens if you attempt it: WK dash/bulkhead rattles solved
Otherwise check out this thread: http://www.jeepgarage.org/f185/squea...sion-9136.html
I get this annoying noise when going over bumps and usually louder in dry hot days in the summer and even now..
I really don't think it has anything to do with control arm bushings... I feel like it's a noise from something being loose coming from within the dashboard or the front sway bar bushings.