Cold start up noise

[wehowardjr]

I was just wondering if its normal for the fan to make an awful rattling noise when started cold, reminds me of failed bearings. With the engine idling It has a slow pulse you can barely hear over the rattle but its there. If I stop the fan the pulse stops but still rattles. I checked the water pump for play and it seems like its good. Once it warms up the motor is quiet and you can barely hear it running with the hood closed. It seems like the colder it is the louder the noise is, when its fairly warm the noise isn't as loud or barely makes any noise. With the motor off the fan turns hard like there's resistance. I'm not getting any codes. Like I said though, once it's warmed up the noise goes away.

Thanks in advance

BTW, a few videos I've seen on Youtube of Trailblazers, not for noise but basic repair How-To's, I've heard the same noise. That's the reason I ask if it's normal.

http://youtu.be/gxsVC4wxPnk