Sunroof Deflector... Do They Work?

Wires · July 5, 2009

I'm finding on my Sierra when I crack open the sunroof, I'm getting nasty standing waves in the cabin which gives a pretty annoying "whommpf.. whoommf.." sound that hurts the ears.

I noticed that my old Acura and my BMW both have a plastic comb piece that pops

up. Until now, I didn't know what that was for, but it actually breaks up the airflow, so you don't have the issue.

I'm wondering if I put on a deflector on the roof that the noise would go away?

MS3DALE · July 5, 2009

Mine has a fabric wind deflector that pops-up,No wind buffering at all,Its pretty quiet.

lilnotts · July 5, 2009

mine has one of those plastic things that pops up when its open

DofD · July 5, 2009

Mine too has a small plastic deflector that pops up and I haven't noticed any wind noise like that.

punmax · July 5, 2009

This happened to me once so far in my Escalade. I'm pretty sure those deflectors eliminate that problem.

superjim · July 5, 2009

Mine has a deflector and I don't have what you are describing.

Obviously I have more wind noise when it is open, but no buffeting like you are talking about.

At highway speeds...Mine makes more noise when it is just open a little bit, than it does when it is fully open.

omegafiler · July 5, 2009

Yeah, the built-in deflector works fairly well. I mean, just push it down, and you'll see what I mean. But I'm normally driving at slower speeds if the sunroof is open, otherwise it's just too noisy.

Jeff Staples · July 5, 2009

My '85 prelude has a pup up deflector...driving 60 miles an hour you cant hear any of the noises youre describing, however if I push the deflector down the wind will start that whooompf noise like youre saying, so yes, thats the problem.

Darkanion · July 5, 2009

I've been trying to think of things that would effect the airflow over the truck. Do you have anything attached to the front of the vehicle (the hood perhaps?) or covering the bed? Have you done any interior modifications (sound dampening, perhaps?) that might've covered up some of the venting that GM builds into the vehicles?

Wires · July 7, 2009

I've been trying to think of things that would effect the airflow over the truck. Do you have anything attached to the front of the vehicle (the hood perhaps?) or covering the bed? Have you done any interior modifications (sound dampening, perhaps?) that might've covered up some of the venting that GM builds into the vehicles?

Nothing on the hood, just a rollup toneau cover on the bed. Nothing blocking vents. Interior was left stock. I'll check it again, I don't think there is a pop up deflector (I know what you mean though). Maybe it's defunct?

Darkanion · July 7, 2009

Nothing on the hood, just a rollup toneau cover on the bed. Nothing blocking vents. Interior was left stock. I'll check it again, I don't think there is a pop up deflector (I know what you mean though). Maybe it's defunct?

Alright, I was just curious.. There "should" be a pop-up deflector on your's. Maybe it is stuck down or missing or who-knows-what.. Also, have you tried the sunroof experiment with the tonneau rolled-up, just to see if it makes a difference?

Wires · July 7, 2009

Hmmm. armed with a beer I hit the garage. When I crack it open, there is a pop up "comb" that I was wondering about. I'll have to take it for a drive once the rain stops and see if it works. I'm 99% sure nothing was popping up the other day when I was getting those standing wave issue.....

Darkanion · July 7, 2009

Hmmm. armed with a beer I hit the garage. When I crack it open, there is a pop up "comb" that I was wondering about. I'll have to take it for a drive once the rain stops and see if it works. I'm 99% sure nothing was popping up the other day when I was getting those standing wave issue.....

If it's not always popping-up, I think I'd take that in to have it looked at.. Better safe than sorry, especially if something is binding-up. You don't want a leak, on down the road.

Wires · July 7, 2009

Hmmm. armed with a beer I hit the garage. When I crack it open, there is a pop up "comb" that I was wondering about. I'll have to take it for a drive once the rain stops and see if it works. I'm 99% sure nothing was popping up the other day when I was getting those standing wave issue.....

If it's not always popping-up, I think I'd take that in to have it looked at.. Better safe than sorry, especially if something is binding-up. You don't want a leak, on down the road.

Thanks for the advice. Totally forgot to even try the sunroof today when I was out. I'll try it with the toneau rolled up as well. Looks like I have some "driving around looking busy" on my hands!

mato27 · July 8, 2009

My wifes Explorer has a pop up deflector on her sunroof and she definately gets that sound, but only at slower speeds. After trying everything imaginable to get rid of it, I found the only thing that works is to open one of the windows about 1/4". Let us know if this works for you