High Speed Interior Squeal

[evanspears]

Hi Guys,

First time post, and looking for some help from this great site! A week and a half ago I purchased a 2007 Silverado with 25xxx miles on it, and so far I love it, with one exception... When I get the truck up to 80ish mph (or less depending on how bad wind is gusting) I get a terrible squeal/whistle/resonation in the cab of the truck. I think it is coming from either the windshield seal, or the onstar/xm antenna. The reason I think this, is when I hear the noise, I can slide my fingers kind of in between the roof, and the windshield, and I can feel it vibrate/resonate, and if I apply pressure between the two, I can change the pitch of the whistle.

Has anyone had any experience with a squeal like this, or have any ideas as to where to start in troubleshooting this problem? Should I take it back to the dealership and have them look at it? Thanks in advance for the help, and this site is awesome!

-Evan

[S4VILL3]

it could be the windshield, maybe from the factory or an aftermarket one installed improperly, in a truck i had we used silicone to seal under the rubber seals on the sides of the windshield and also sealed the shield inside the cab, this may help.

[Shopkins]

does the truck have a bug shield on the nose of the hood? if so this is very likely your cause. customers complain about that all the time at my shop. i'm a GM tech seen it a hundred times. if you do have one try taking it off and driving it again.

[Shopkins]

kinda left out the reason ha. to further expalain the bug shield deflects the air in such a fashion that it hits the upper windsheild seal causing the noise.