Anyone have a somehwat of a loud sound when
 

the X is real cold from the engine? any idea?

Be more descriptive. When? How often? What type of sound? What year and motor do you have?

Just read your sig with engine info. When did this start?

It's been mentioned before, but..

Everytime - even in WARM weather - when I start mine up, there is a very disquieting RATTLING sound for a minute or so. It seems to be perfectly normal.

I never noticed it because I'm always IN the car when I start and once a passenger was not quite in the car and said "What's that racket? It's not from YOUR car, is it?"

Then of course I heard it.. A very distinct RATTLE. Like something is wrong / loose / going to break soon. It is really quite loud, and as I said, DISTINCT.

Many have reported it. I don't know if it just comes from the new engine or what, though. As I recall, the thread never really met closure as to the cause.

What's your production date?

I think I have the same thing in my 11. I heard it in my 09 as well. almost like a loose heat shield or skid plate, right?

The 3.0's prior to 11/31/08 have a defect in the motor. This is really related to ticking heard from the engine in the form of valve noise. The defect specifically relates to the head. For customers that complain and the diagnosis is done via the dealer, they will replace the head assembly with the newer part.

Mine is a 2011, built at the end of August. It's really quite a rattle, but it goes away after a minute or so. Hot or cold. I do have it on my list to ask about when it goes in for service, but that won't be for quite awhile (just crossed 6600 miles).

<trying to describe the sound..>

Not unlike if you stick a piece of cardboard in a running desk fan. Louder, maybe. Again, can't hear it inside the vehicle and it doesn't last long.

Others have mentioned it too, so I rather just assume it's normal, but it's certainly not a sound you expect from a gasoline engine. It sounds like it would be more at home on a diesel.

I had a tapping sound. Dealer replaced all the lifters. Somewhat quieter now.

If it's like mine, it seems to be comng from the catalytic converter. Once u hear the noise if u crawl under your car and hold the cat) looks like another muffler but right in the middle of ur car) the noise stops. I don't know if there is something loose in the cat, but it's definately coming from there. If u have the windows down and the car is under load u can also hear it then. Haven't taken mine in yet.