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Driving With Sunroof Open...Impossible!!!


Charter Member
Full Member
Apr 13, 2002
Im sure this has been subject of a number of posts before but cant seem to find them... ???

My Question is...
What causes the thundering in my eardrums when i try to drive over 50mph with Sunroof open and the rest of the widows closed. ?And What is the solution , Im guessing some kinda wind deflector, if so Is there a OEM part # any kind member can facilitate!!

Thanks . ?
I think it is back pressure, I have just opened my drivers window to release some of the pressure. But after seeing this post I too wonder if there is another solution! :cautious:
Common with any closed vehicle and a sunroof. Some of the large acrylic deflectors can help. I just crack open the rear door windows. Another nice solution with the AV is to take the back window out. All four door windows down, sunroof open, and the back window out - almost like my Vette convertable! Both are a lot of fun...Cheers - Jim
Unfortunately this is nature at work....and like the folks already said...just crack a window and it should go away....if not then you may have a manufacturing issue... :B:
I have the same problem. When I have not used the sunroof for a few days it feels like the roof is about to vibrate right off. I need to close the sunroof about 3 inches to solve the problem. It occures around 35 MPH in my AV. Interestingly, if I park it overnight with the sunroof open I don't have the problem. Upon further investigating, if I have the problem and then slightly push up on the spring loaded deflector at the front of the sunroof it goes away. Reach up and try it. I would try it and then show the dealer. Maybe it is just a weak spring on the deflector or the spring is installed improperly.
harmonic reasonance, not germane to just the Av, have exeperienced the same issue with other SR vehicle. All you need to do is crack (a little crack is all that is needed) a window (I tap the down key for a sec on one of the back windows) to relieve the pressure, and the reasonance will cease. I drive with my SR open all the time. Not a big deal to me.
Search for SUNROOF....there is a thread where the chief discusses this....

If you have the roof rack move the forward bar back at least 9" behind the sunroof opening.

To rid youself of this noise just crack a rear window.

How I solve this problem...

1. Open sunroof
2. Open all other windows
3. Remove rear window
4. Crank stereo
5. Have fun ;D

Just picture opening the window on a jet airplane and you can see where the noise would come from. When air hits the opening at high speeds, it's going to make noise. :D
ygmn is right ... if you have roof racks move the front bar as far back as possible and that takes care of most of the noise.
good luck,
Now careful folks on the search engine rant. ?For the old timers, charter members you'll remember this one because it was the VERY FIRST POST on the site. ? ;D

Here is a picture from above...


Now notice how far back the first crossbar is on my roof rack. ?It's about parallel with the "B" pillar and well past where the front door meets the back door, and well back from the sunroof. ?There is a TSB on this issue and it is not a "design defect" or unique to the Avalanche.

I also did do a long post on the aerodynamics involved. ?If you have your sunroof open it is best to crack at least your back windows about 1/2 inch so that the pressure can change evenly in your cab. ?Otherwise the area of low pressure pushes builds until the flow is broken and the inside "buffets" from the pressure changes.

The only car I've ever owned in my life that had a "perfect" sunroof was my 1989 Ford Probe. ?Of course the car also had a coefficent of drag under .29

Hope this helps!
So I was trying different stuff with my sunroof, I tried to see if u had the fan going full if that would stop the ressonating...didnt seem to help.....tried lowering back window ....seemed to help...then I pulled down on the spring loaded flap.....WOW did it ever pound...try it some time, you wanna hear and feel pressure :2:
I have the same problem (no roof rack). A while back I read the post, then I e-mailed the poster to see if he ever got it fixed (I can't remember who it was). Anyway, he said the dealer replaced the deflector and it solved the problem. I haven't taken the time to take mine in, so I can't say for sure.
I have the same issue. Would like to hear if there is a retro fit. If I move the sunroof 3 - 4 inches forward the noise will stop. BUT there has to be a better solution!
mjmenke indicated that 'the noise stops when you push up on the spring loaded wind deflector.' This is how the deflector is constructed. I am curious why it must be pushed up though. Mine is, as mjmenke indicated, spring loaded, and goes up on its own. If you want to really treat your ears, drive approximately 60 km/h (40 mph) and pull down on that wind deflector, keeping all of the other windows closed. :)

There will always be some noise with the sunroof open at high speed. But things can be done to minimize it, as others have indicated. Opening windows, removing windows, and adjusting your roof rack will all help to minimize noise.
Can anyone please answer this question. Can you feel any wind coming in with all the windows up and the roof open ?
TON AV 1 said:
Can anyone please answer this question. Can you feel any wind coming in with all the windows up and the roof open ?
Not that I've noticed. I will check it out further on the way to work!
TON AV 1 said:
Can anyone please answer this question. Can you feel any wind coming in with all the windows up and the roof open ?

I tested mine on the way into work this A.M. . At speeds above 25mph or so, I start feeling some wind in the cabin. It occurs at head-level and is the most noticeable at the center of the sunroof and a few inches back from its rearward edge. I also noticed a small draft coming from the door handle opening.
TON AV 1 said:
Thanks Steelhead. Is the sunroof worth the thousand bucks ?
Actually, you can't put a price on the "Ohhh, I wish mine had a sunroof ?:(" you get from the non-Sunroof AV owners.

But, GM can ?;D

BTW ... definitely worth it.
goo929 said:
Actually, you can't put a price on the "Ohhh, I wish mine had a sunroof ?:(" you get from the non-Sunroof AV owners.

But, GM can ?;D

BTW ... definitely worth it.

I second Goos comments (y)
Well I'M not sure what you call it but its like air is coming in the cab through the SR, it has to go out some how (trys to go out through the same place it's coming in) what I did was installed a ventshade wind deflector they also look pretty cool. it helped.