I just couldn't take it anymore.

It seams that although well intended, GM didn't do their homework with the sunroof wind deflector that pops up when the roof is opened.

Some of you guys have mentioned having the same problem of an annoying "buffeting" with the roof fully opened at speeds above 40 mph. What I noticed is that if you hold the wind deflector down with your hand, the "buffeting" noise/pressure goes away.

No Tools or Extra Parts Required Fix.

Open the roof so the deflector pops up.
There are 2 small meteal springs that force the deflector up.
Gently slide the springs towards the center of the car and they will pop out.

The deflector now stays down with the roof open and the roof still opens and closes properly.

http://www.g8board.com/forums/attachment.php?attachmentid=978&stc=1&d=1210857351

http://www.g8board.com/forums/attachment.php?attachmentid=979&stc=1&d=1210857351

http://www.g8board.com/forums/attachment.php?attachmentid=980&stc=1&d=1210857351

http://www.g8board.com/forums/attachment.php?attachmentid=981&stc=1&d=1210857351

I had the same problem on my Hellendia 710 I had installed in my GTO. Was really noisy. Just took the deflector out. Will probably do the same on the G8 as it involves a screw or 2 on each side. Avoids the possibility of the thing rattling. Surprisingly, the G8 sunroof is actually a bit smaller than the 710, which is the size that was installed at the factory on Australian Monaro's.

RRM

Thanks for the info on the springs. There was another thread where they added tire weights to keep it down also, seems better to pop the springs until a real fix is made.

I just crack my driver's window open. It doesn't even have to be visably open and that seems to eliminate the pressure "rumble" as well.

Resurrecting an old post since I tried this tonight. It did seem to remove some buffeting at high speeds... but introduced much worse buffeting for me at low speeds, to the point that it actually rattled my headliner loose. I put it back to stock for now until I find a better solution.

g.m. has an updated deflector. i installed one on my car appx. 1 year ago... fixed the problem.

What did you have to do to get the dealer to replace the stock deflector?
Can you post a pic of your new deflecter?

Sent from my PC36100 using AutoGuide.com App

the deflector keeps alot of the wind from rushing down
between the headliner and the underside of the roof.
suprised it didnt rip all the way out.