On any cool morning (relative to San Diego weather) while putting away from my house I always get a squeal that sounds like a slipping fan belt. It's not the belt.

If my wife sits in the truck and slowly presses the pedal while I listen around under the hood, It seems to come from the back of the engine, turbo area, flexplate maybe, tc.

It occours more or less around 1000 rpm. When cold it's a really obvious raspy, I'm ripping the guts out of something sound. Much less so when warm.

Does anybody else get this? Any Idea what it might be?

Yes, I get a squeek also. I notice it when coasting in a parking lot then applying a light throttle, I will get the squeek. Not sure what this is, tried telling the dealer and got that look!!

2004 2500HD
D/A
Ext-Cab...LT

Don't you love that look? Like you're the biggest idiot of the day, because you took time out of YOUR busy day to take care of your $45000+ investment.

Last time I was in (for the door squeak) they finally gave me a rental car, big long sigh from the service writer when I asked. It took 3 hours to get rolling in the rental. I was behind at work all day and got back just in time to get the rental returned before Hertz closed. I RAN 2 blocks back to the dealer (in dress shoes) but it was 6:03 and they wouldn't give me my truck back. Closed. A few people were still there but no, come back in the morning. That was trip two for the door squeak, I haven't had time for trip three yet.

Believe it or not, I have a GMC because the Chevy dealer across the street is much worse! Two vehicles from each in twelve years, not a high volume customer I suppose but jeez about a hundred thirty thousand in retail purcahses should get some respect. Don't you think?

I suppose that's off topic.

Any Idea what causes the noise?

I started a thread a couple of days ago about the same thing. I think mine refer to a chirping sound coming from the same area as yours. My dealer has spent six days on the problem and will tackle it again next week. So far the a/c mounting bracket TSB, idler pulley, a loose heater core and the temporary complete removal of the turbo shields hasn't helped. Someone said a new water pump fixed his. I tend to agree with you though, it sounds like its coming from the turbo more that anyplace else.

I'll cross post and let you know if I have any luck.

Here's the link to the other thread about the same issue. http://dieselplace.com/forum/showthread.php?t=42898