jmitchell

There is a lengthy discussion about this here with a very cheap work around. I've done the cheap version for my i-products but there is someone who paid the mega $$$ to get the custom package installed. Hope this helps... http://www.tahoeyukonforum.com/forum/showthread.php?t=63504

I have a 2015 Tahoe and have the same squeak or whistle noise coming from the exhaust only when going from V4 to V8. Thanks to this forum, I'll be fixing this annoying problem tonight!!! Thanks for the info guys.

If you have the roof rack cross rails then I'm almost positive it is coming from the rear one. I had the same issue going over bumps could hear a rattle that seemed to be coming from the rear. If you open up a rear door, stand on the sill plate, then hit the chrome section of roof rack you should be able to duplicate the rattle. I was unable to tighten the cross rails enough to keep from rattling so I stuck some tape in the gaps at the end of the rails where they slide into the female fitting. If you need a picture let me know.

I hope GM can find a resolution to this. Knock on wood I have not had this issue yet but it also hasn't been that warm here yet. Watching the last video you posted it seems that the top of the spoiler may be catching at the roof line. Have you gotten on a ladder and watched the top of the spoiler while it goes up? I'm sure you've looked at everything but just an observation.