I have a 2000 ssei that has a rattle in the left rear, only when going over bumps, usually at a lower speed. Have pulled the rear door apart and everything seems ok there. Have checked the rear suspension and everything seems ok. Any thoughts?

Pull the back seat out and check there. Also check the trunk and make certain that all the trim pieces are in their respective places and not hanging or dropping. Look in the spare tire area, and tighten down the retention system for the tire and jack.

After almost a year of trying to find the same type of rattle, new shocks, shock mounts, and rear torision bar to no avail I finally found my problem. There is a body mount just under the rear door, mine had somehow rusted through around the mounting bolt causing the low speed rattle. After removing the bolt inserting a larger washer and retightning the bolt the rattle is gone. Hope this helps. I can email you photo'* if you want. I don't know how to post photo'*

Thanks Peej9089, that was indeed the problem and your fix worked.