I had several rattles in the Lexus and I finally got them fixed.
One rattle was coming from the rear area: I actually found two, one was coming from the drivers side quarter panel - after removing the panel I found couple possible rattling loose wires (mainly the rear acc. plug was disconnected), anyway after reconnecting the plug and using couple feet of self adhesive weatherstripping tape the rattle went away. I also had some additional rattles that was coming from the rear that I think I may have fixed. It was the seat belt buckles from the second or third row seats. Anyway since I tucked them back in there slots the noise has gone away.
As for the rattle coming from under the dash: My rattle was coming from around the glove box. At first I thought it was the misc. items I had in the glove box but even after removing the contents the rattle was still there. So I removed the glove box and found that the source of the rattle might be the shroud that covers the uppper interior of the glove box. So I removed that and found that it's only held by three screws and with the mettle bracing and other components tucked away under the dash that it was rattling against. I used another couple of feet of the weatherstripping tape and reassembled everything and took if for a test drive on the crappy roads of the Portland, Or. highways. They allow studded tires here and it just destroys the road.
The final results: Not a single rattle!!!!!!!!
In fact the funny thing happened the other day, the car is so quiet and rattle free that I heard something rattling and I thought oh no the rattle is back. When in fact it was the rattle from my jacket zipper.
Rattle free and loving every minute.
