Pretty much everything made out of plastic or metal
I've spent countless hours finding rattles in my last 2 cars. I'm getting to my limits on the SSEi I can still hear some rattling but nobody else can. Anyways other than checking for rattles from the main things listed above. When checking for interior rattles, I would sit in the back seat with a nice bass beat and push and pull on every panel or whatever and listen to if it got better. When you find something, most times it'* plastic on plastic is the culprit. But I gurantee that metal will flex and cause noise as well, The first time I say/heard my sunroof open when tuning with a bass mechanic CD, The roof was oh jumping 2-3 in. Just waiting for my glass roof to break. Thinking about dynamating my roof, to prevent this. I also hear that once you do the roof, it'* amazingly quite inside.
Anyways back to interior rattles, from my experience, both of my rear decks have rattled, I've taken them both apart and Dynamated them, put it back to gether and still had some rattling, trick my installer should me, if you can put 1 or 2 small screws into the rear deck where not visable, this will tighten the space between them and not allow them to slap and vibrate against each other. Another trick l learned from GM actually , On the aurora ALL the interior panels where stuffed with some sort of padding or cloth. When I took the Bonneville apart, the panels are empty. That leaves room for resonance and vibration.
Most important, use Dynamat or some kind of damping material. This will help drasticly with rattles and just general road noise. Doing the front doors will make the ride SO much quietier, Yes my front doors rattled too. The less road noise you have the better, you can hear more of your music, the mids and certain frequecies are covered by some road noise. Lowering road noise with dampening material will make your stereo sound MUCH better and cleaner than without not to mention helps fights rattles and metal flex.
Hope this helps, just start pushing on things and figure out what'* rattling. Then secure it solid with something however you can and use dampening material.
Dynamat Extreme Bulk packs on Ebay 36 ft2 for $99. One is enough to do your trunk and have some left over. Well worth the cash for a better quieter ride. Can you tell I'm a Dynamat freek. Stuffs very easy to install if youve never seen it, peel and stick.
2001 SSEi 13.731 @ 101.59--->PICS HERE <---
--Intense PCM--2nd gen LSD--3rd gen Rockers 1.9 --#105lb springs--oil restriced pusrods--Intense shift kit--TEP CAI--ZZP mod 3.4/3.2 --IAT relocate--TOG silver ceramics--SLP CAT--o2 fake--160 stat--PRJ 10.4mm wires--Autolite 104'* @ .055--MAP TB heat shield
--Custom mesh grill--Cleared front and rear corners--Angle Eye'*--Silverstars 9006+9005+H3--PONTIAC 3rd break light overlay--Embrodered PONTIAC head rest wrap--Arrowhead inlays for front+rims+steering wheel--Zaino polish
--Alpine IVA-D300 7in TV--two 10W7s--JL amps 1000.1 & 450.4--MB Q'* 6.5in Comps--Optima yellow top--5 farad cap--lots of dynamat extreme--Custom install w/ plexi and mirrors--Sirius radio--compete in Sound Quality!!!
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