i have an '03 ES with about 76000 miles. earlier this year it started to develop a strange and very brief shaking sound when i went over a manhole cover or the joints on a bridge. it was a rather violent and sudden shaking/rattle sound but it did not affect ride quality or handling.

i know the usual culprits of my car but these are not it:
rear view mirror (usually only in the dead of winter)
door panels (usually in the winter also)
aftermarket stereo (a different vibration and i just have to hold the stereo for a few minutes until the vibration stops)
change in the car (all the change is out of the car and still get the sudden shaking)
short shifter (i bent the heatshield so it doesnt make contact with the linkage of the shifter)
trunk rattle (everything in the trunk is secure)

one thing i noticed when i went to close the hood the other week, as the hood slammed shut i could hear the exact same brief rattle from the outside. i would say it was just as audible from the outside as the inside. the sound occurs on any hard surface change like a pothole or manhole cover, or even a sharp speed bump. i try to avoid these anyway and i do not drive over them in excessive speed but the shake will still be there. any ideas? thanks

 

If you can repeat it by slamming the hood.... repeat and follow the sound

 

i tried, the car suddenly seems a lot bigger when you try to search for a noise that isnt constant and loud like an exhaust leak or something.

 

try checking your stabilizer bar links i dont know if you would be able to duplicate the problem by closing the hood but you will if you go over a bump