As posted here:
http://www.toyota-4runner.org/showthread.php?threadid=3626
my 4runner had a rolling marble/rattling sound coming from the front driver's side area. Supposedly this was resolved last week. Now rattling has returned but a different kind of rattle and I can't place where it is coming from. It sounds like a vibrational rattle and only occurs when street surface is rough/bumpy. I removed all loose items from the inside of the runner to make sure that these items were not causing the noise. Made no difference...rattling still there. My vehicle has been worked on three times for "rattling" noises: moonroof TSB repair, additional insulation in headliner and replacement of sub-base assembly. I am very fed up with this. I like the performance and comfort of my 4Runner but am disappointed in the construction. I will be calling the service dept. as well as Toyota tomorrow. At least I had a few days of quiet comfort without any rattling.

http://www.toyota-4runner.org/showthread.php?threadid=3626
my 4runner had a rolling marble/rattling sound coming from the front driver's side area. Supposedly this was resolved last week. Now rattling has returned but a different kind of rattle and I can't place where it is coming from. It sounds like a vibrational rattle and only occurs when street surface is rough/bumpy. I removed all loose items from the inside of the runner to make sure that these items were not causing the noise. Made no difference...rattling still there. My vehicle has been worked on three times for "rattling" noises: moonroof TSB repair, additional insulation in headliner and replacement of sub-base assembly. I am very fed up with this. I like the performance and comfort of my 4Runner but am disappointed in the construction. I will be calling the service dept. as well as Toyota tomorrow. At least I had a few days of quiet comfort without any rattling.