Up till now, my ML430 has been remarkably rattle free. Within the last week I've noticed a persistent rattle coming from the rear hatch area. I tightened down the tire jack/lug nut assembly in the right storage bin and thoroughly checked that area for something loose..couldn't find anything. The CD changer + bracket was removed a few months ago. On the other side, that storage area was secure as well with only the first aid kit in that compartment . BTW, what IS that removeable plastic piece behind the first aid kit? Can't figure that one out.

This evening I removed the entire rear hatch cover to check all those assemblies..everything seems secure and tight. Anybody else had a similar rattle in this area ?

Try to adjust the two nuts with rubber head on the side of the read door frame. Those two nuts controls how close the door can be shut. It fixed 90% of my tattles, the rest 10% is from the door pull pocket, some home depot felt took care of that.

Make sure it's not your seat belt buckles in the back rattling against the plastic trim. Mine do it with the windows down.

Can't believe I never noticed or adjusted these before ! It took all of one minute to adjust both of the bumpers and like magic.....no more rattle !!!

Thanks for the tip!!!

Yep. Mine rattled for like five years before I noticed those bump stops. I can't believe my dealer never adjusted them either. They just threw on some new felt every time I complained, and it lasted all of about two weeks. I hasn't rattled in a couple of years since I adjusted the bump stops, though.