I've got a 2013 ES 350 with about 150K miles. Love the car, but I've had some slight rattling in the suspension for a while now that is pronounced when coming out of the driveway, going over small bumps but not so much once I'm up to speed or the car is warm. Colder temps also seem to make it more pronounced. No issues with the feel of the car but the sound is annoying. Based on Internet sleuthing I thought it could be the sway bar linkage, but after really shaking both ends at the connection there is no play and no noise. Bouncing the suspension in the garage by putting weight on the frame doesn't produce anything either.

​​​​​​I really only hear it at speeds of 10 MPH or less, and going over small bumps. I tried a swerve test and no sound there. It's pretty much when the car is pointed straight, going slow and going over bumps or imperfections in the road. I really hear it coming in and out of driveways. Colder temps also seem to make it more pronounced. Any ideas? Thanks for the help.

 

These things are almost impossible to diagnose over the internet. Cold always makes things sound worse as the metal contracts.
You need a reputable independent shop to put it on a lift and inspect the suspension and underneath areas of the vehicle. With that many miles it could be so many different things I will not even begin to list them. Use Google or Yelp or ask friends to find a good local shop if you do not have one.
I would stay away from the dealer as they will overcharge, probably misdiagnose and then tell about 17 other very expensive things they want to repair and replace on your 12 year old vehicle as the service writers work on commission.

 

I had a similar rattle - could swear it was coming from suspension. It turned out to be the sunroof. A $50 sunroof seal fixed the problem.

 

I have a 2014 ESh with about the same mileage (~150K) with the exact same symptoms. Please let us all know what you find out. Meanwhile I will check the sunroof.

 

Just tilt the sunroof up (or open it completely), and if the sound is still there, it likely isn’t the gasket. Might still be something in the tracks though. There have been stories about bolts and other fasteners working loose, although not many.

 

Signed up to say it was the sunroof! I could have sworn it was in the passenger side rear suspension too. A "dub dub dub" sound going over road imperfections, or even just easing out of my driveway and driving over pine cones. Been bothering me for weeks, until I saw the post above. Thank you!

 

Hmm. WIll check the sunroof. My car's roof was destroyed by hail in the famous Denver hailstorm of 2017. Since the car was still reasonably new, the insurnace company refused to write it off. They cut the original roof out and put a new roof in. I have not noticed any problems since 2017, but who knows how many fasteners are missing.