It's an 08 TL Base

This was the fix applied for a different issue:

The car has already had the rear shelf rattle repair for something related to the sub. They insulated the high mount brake lamp, rear shelf, center rear seat belt. Sound deadening material applied to all rear shelf speakers. Replaced center seat belt, insulation pad installed, etc. I think that fix is listed somewhere on here.

Anyway the problem I am having is:

Constant rattle from the rear area not related to the previous one. When it's cold outside, and it's not sunny / the interior temperature is colder, the rattle is more prevalent. At night when it gets really cold the rattle becomes a worse squeaking / creaking noise that is amplified when the roads are bad. It's coming from somewhere near the rear headliner / glass / rear deck, but I don't think it's related to the rear deck. The noise can be heard with the volume on 25 or so.

Any ideas / suggestions?

Thanks in advance

 

I have an 08 TL-S and had a very annoying rattle from the rear shelf area. Had it to the dealer 3 times, they did all the insulation on the rear deck, sub, replaced the seat belt,etc. Still no fix. Last week they finally located the problem, 3rd breaklight area, there was a piece of metal flashing that was rubbing against another piece of metal. They bent the flashing out of the way and the rattle is gone.

I also had a horrible rattle from the airbag in the steering wheel, that took 2 visits to get fixed. Very annoying for a car that stickers for almost $40k.

Good luck.

 

I am having the same issue with my new 08 TL. A creaking/rattling sound coming from the rear deck area. It happens when the radio is off so I know it's not the radio. It first started happening in the morning when the car was cold. I will keep an eye on it to see if it persists in warmer weather. I am wondering if you ever discovered a fix for this problem.
Thanks

 

I was having a problem with a very similar noise. Turned out to come from a very unlikely source. If you look at the brackets supporting the rear mufflers, you'll see a large rubber washer that suspends the muffler. Try banging on the muffler with your palm and see if you get a similar noise. I found that the metal was banging against metal when the road was bumpy enough.

The fix was easy for me. I got a piece of sheet metal about 1/2 inch by an inch, wrapped it in a couple of layers of electrical tape, and inserted it into the middle of the rubber washer. It stiffened up the washer and prevented the banging. Probably anything would work, like a double a battery wrapped in tape. Worked like a charm.

Hope this helps!

 

Hopefully this is the fix to my noise too, it's been really bothering me