Knocking sound driving me insane!!!

[VAguy68]

I've got this knocking sound coming from the area in front and above my head. It only happens at highway speeds and when wind is crossing left to right. It's bizarre but driving me insane. I had the TSB on the sunroof drainlines done and I'm wondering if it can be those that are somehow receiving air and moving around as it sounds like it's comin from inside the bodywork. I've climbed all over this rig pushing and pulling on trim/mirrors, etc trying to find something loose to cause this. Of course I'm at 46K miles and out of bumper to bumper warranty. Anyone else run in to this? 2021 Z71

 

[Doubeleive]

I've got this knocking sound coming from the area in front and above my head. It only happens at highway speeds and when wind is crossing left to right. It's bizarre but driving me insane. I had the TSB on the sunroof drainlines done and I'm wondering if it can be those that are somehow receiving air and moving around as it sounds like it's comin from inside the bodywork. I've climbed all over this rig pushing and pulling on trim/mirrors, etc trying to find something loose to cause this. Of course I'm at 46K miles and out of bumper to bumper warranty. Anyone else run in to this? 2021 Z71

any aftermarket equipment installed? bug guard, pod lights?

 

[swathdiver]

I've got this knocking sound coming from the area in front and above my head. It only happens at highway speeds and when wind is crossing left to right. It's bizarre but driving me insane. I had the TSB on the sunroof drainlines done and I'm wondering if it can be those that are somehow receiving air and moving around as it sounds like it's comin from inside the bodywork. I've climbed all over this rig pushing and pulling on trim/mirrors, etc trying to find something loose to cause this. Of course I'm at 46K miles and out of bumper to bumper warranty. Anyone else run in to this? 2021 Z71

In front and above your head, if you have a moonroof, the only thing up there that could move around in my mind is the deflector. Maybe it got loose somehow? Of course, you're going to tell me you don't have one! LOL

 

[WalleyeMikeIII]

I've got this knocking sound coming from the area in front and above my head. It only happens at highway speeds and when wind is crossing left to right. It's bizarre but driving me insane. I had the TSB on the sunroof drainlines done and I'm wondering if it can be those that are somehow receiving air and moving around as it sounds like it's comin from inside the bodywork. I've climbed all over this rig pushing and pulling on trim/mirrors, etc trying to find something loose to cause this. Of course I'm at 46K miles and out of bumper to bumper warranty. Anyone else run in to this? 2021 Z71

Sharkfin Antenna loose?

 

[VAguy68]

No aftermarket equip. Sharkfin tight. Yes it has a sun roof that seems to be sealed well when closed. The sunroof drain that had to be repositioned with the TSB worked or didn't work depending if the defroster was running creating negative pressure in the cabin. That's the only thing I can think of. When I'm at highway speeds and I run in to a cross wind, the air pressure is forcing something in the sunroof area to move around. ARGGGGG

 

[TollKeeper]

Is the noise present sunroof open and closed?

 

[Doubeleive]

No aftermarket equip. Sharkfin tight. Yes it has a sun roof that seems to be sealed well when closed. The sunroof drain that had to be repositioned with the TSB worked or didn't work depending if the defroster was running creating negative pressure in the cabin. That's the only thing I can think of. When I'm at highway speeds and I run in to a cross wind, the air pressure is forcing something in the sunroof area to move around. ARGGGGG

so if the noise appeared after they worked on the sunroof then I would take it back to the dealer and have them check what they did. if there is nothing outright visible and no bug guard or anything and it happened after the TSB was performed you should still be covered because of the TSB

 

[Pro299]

Could be air buffeting the glass. That's a large surface and under quite a bit of negative pressure at speed that would change rapidly from crosswinds. That would tug on any connectors that are loose or in close tolerance to other surfaces. Have you tried judicious use of pressure on the roof glass inside and out to see if you can mimic the changes in pressure?

 

[VAguy68]

I'll try with the roof open. I've pushed on the glass to no avail. It was happening prior to the TSB but I will try and use that as an argument that they loosened something in there during the process.

 

[Doubeleive]

I'll try with the roof open. I've pushed on the glass to no avail. It was happening prior to the TSB but I will try and use that as an argument that they loosened something in there during the process.

there is a known issue with some of the k2's having a roof buffeting problem it seems to be related to not enough glue used or the metal being to thin nobody is really sure. There is probably a TSB or 2 out there about it.