Hey, you notice that little rattle noise too? I thought I was going insane. Somewhere in the back... and it happens intemittently. The good news for me is that it went away after about 1000 miles or so. I suspect it's a product of the tight tolerances that the Toyota manufacturers have when they put these vehicles together. After enough normal use the HiHy "loosens" up a little and those weird tinkering noises should go away...

-Han-