Void Warranty?

Has anyone heard if bolt-on's such as CAI, or TBS voids factory warranty? I've read on the web that is doesn't, but the service manager at my dealer today told me that it voids the warranty on the engine in GM's eyes, but that they can tell if anything was caused by the bolt on.

if they wanna be real pricks about it they can, but most of the time there so greedy they dont even care, those techs will still take the job because they want those flat rate hours.

The Magnuson-Moss Warranty Act (a federal law sometimes called the lemon law) covers that.  A manufacturer doesn't have to fix problems specifically caused by a third-party product, but they can't just void the warranty on their item because the third-party product is being used.