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Flapping noise....??

CASD57

Full Member
Joined
Dec 22, 2020
Messages
93
Location
Meridian, Idaho
I got this flapping noise when your driving down the road and go over bumps... Like a sheet flapping on a clothes line...
I did check the wheel wells for loose plastic... I found that the insulation inside the front fender loose..I can move it through the passenger door by the hinge
I'm thinking that this piece is floating around inside the Fender...
Is this something that has come up before? loose insulation inside the fenders? looks like felt
 
First I have read about it on here
 
Honestly...it could even be coming from inside a passenger door or even Moonroof... It's hard to pinpoint and so far no one else hears it lol.. (passengers) it's like something is floating around bouncing into things as I drive...
I keep thinking that wind is getting in somewhere and bouncing something around like insulation... Probably why the last owner only had it a year or so lol..... it will drive a mechanical person nuts
 
Have others drive it while you sit in other positions, passenger, rear right and left.
Open midgate as well.

Check side bins for loose crap rolling around.
Check inner fender liners for all their clips are secure to keep it from flapping.
Check windshield rubber trim for flapping (issue on 1st gen with bug deflectors)
Check for loose body mounts or space.
Check front suspension parts
Check midgate and rear window properly shut

The list goes on....
 
I have the same thing. Pretty much when driving between 45-60, there is constant flapping. Not usually when slower or faster. I keep thinking it is coming from the back right, but cannot find anything.
 
Last edited:
There are vents in the lower corner for when you close the doors or using ac and when you open the sunroof and the deflector is broken.
 
I have the same thing. Pretty much when driving between 45-60, there is constant flapping. Not usually when slower or faster. I keep thinking it is coming from the back right, but cannot find anything.
Mine too....or that was my first impression....It seems to move..from the passenger door.....or post/pillar to the back passenger side..sometimes it sounds like it's in the roof.....to pillar to back weird but I will find it in the next few weeks...we are looking at another storm coming in tonight, so the noise will have to wait for better weather... I'll post when I figure it out :)
 
I had rescrewed the loose back passenger wheel well plastic cover..... airing up the tires yesterday I notice that the back driver side inner wheel well covers was even more unscrewed...Lost screws about half way up 4-5 of them(didn't count) So I screwed them(New screws) in so both inner wheel well protector covers are securely fastened. Didn't get a chance to drive it last night and I didn't notice it this morning driving to work but I should if I'm going too..on the way home, I'll keep you posted
 
Sounds good, that will be great to know if that is the problem. It should warm up here in a few days and then I’ll take a look at mine.
 
Have others drive it while you sit in other positions, passenger, rear right and left.
Open midgate as well.

Check side bins for loose crap rolling around.
Check inner fender liners for all their clips are secure to keep it from flapping.
Check windshield rubber trim for flapping (issue on 1st gen with bug deflectors)
Check for loose body mounts or space.
Check front suspension parts
Check midgate and rear window properly shut

The list goes on....
I have a "Flapping' noise too, it happens at 60mph and above. I hear it from under the drivers side of the dashboard, however, my passengers hear it from the top console? It's so annoying. I'll check the things ygmn suggests. Unless there is more to the solution?
 
it could be from the air deflector on your hood. I get the same thing and recall seeing some posts in years past about how the windshield is sealed and the deflector disrupting it.
 
yes cladded with hood bug protector thingy... when you drive air coming off the ends makes the windshield seal flap against glass.

Fix was 3m tape the seal down or glue.

Was part of specific instructions from GM bug deflector.
 
Both my wife and I hear it in the roof...to the passenger side.. We have a moon roof, maybe some insulation in the roof has come loose,
What is weird is that if I crack the moon roof or window, I can't hear it...Like its pressure-related but it also be that it gets noisier also and I can't hear because of the wind noise..
I'll find it, but it needs to be warmer outside before I tear into it...
 
I remember older threads talking about the placement of the roof rack cross bar in the front and how sound/wind is deflected causing noise for some owners, they moved the cross bar up or back to eliminate noise. You may want to try moving it if you have a roof rack?
 
Update....Maybe:
I washed the Avy this last weekend and I noticed the roof rack cross bar on the passenger side was really loose (2-Screws underneath the end) where ready to fall out, Tightened them up using a 90 degree Philips screw driver and moved the rack back about 3-4 inches getting it farther back from the airflow..and so far I'm not hearing the noise.., I'll update in a few days to verify that this worked.
 
I will have to take a look at my roof racks. I checked out the flaps inside the wheel wells, and that was not it. I will check the rack this weekend. Thanks for the update!
 
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