Noise in dash vents on 2010 sierra

[NCParamedic]

I recently purchased a 2010 sierra crew cab and have noticed a rattling type of noise in the dash vents when the fan is turned up half way or more. The dealer is trying to tell me that its just air moving through the vents. I'm not buying that. My dads 09 doesn't do that. I doubt its a leaf in the dash since it was on the showroom floor when I bought it. Anybody have any thoughts or noticed the same thing? It doesn't affect the amount of air moving through, its just annoying. I've also noticed that if I turn the wheel that closes off the two vents closest to the radio just a slight amount the noise goes away. I'm thinking it could be a bad vent assembly. Thanks!

 

[GMC Customer Service]

Did you take the vehicle to the dealership that you bought the vehicle from? If you did you can take the vehicle to a different dealership for a second opinion of sorts if you would like. I hope that helps you. If you could please keep me up to date on this issue as well.

Jeff Morris, GMC Customer Service

 

[10gmc]

I here the same thing, wife says im nuts. Keep me updated so i know what its caused by. Thanks

 

[NCParamedic]

Got it fixed! Took it to a closer dealer and they knew just what was wrong as soonas I started to describe it. It has to do with the foam insulation on the dash vents. Service advisor said there was a service bulletin about it. I was in and out in an hour...with a free wash!