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      12-30-2021, 11:23 AM   #1
jfritz27
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Questions re: potential clunk/knock from swaybar/endlinks

Hey all, appreciate any input here.

I have a '17 ZCP (stock sway and endlinks), with the B16 Damptronic kit paired with Vorshlag camber plates (these were installed about 10 months ago, and impact gun top nut tightening was done as per Vorshlag instructions), with a fairly mild drop. I've developed a front clunk/knock going over bumps. I'm worried it could be related to camber plate bearing issue (though they haven't been on the car that long), but want to cast a wide net.

I've never dealt with changing out swaybars or endlinks, so am trying to figure out if that could be an alternative cause. What makes me think that it could be more in that area is that over harsher bumps at times I can feel the clunk transmitting to my feet. Also, I can hear something occur when the front end "twists" like when the car first crosses from my street onto my inclined driveway.

I took off the front wheels and with my hands tried wiggling the bar and the 2 endlink ends, and couldn't clearly induce any play. Nothing visibly looks awry. Does that exclude any problem, or perhaps some issues but not all (like an issue with the bar bushings themselves)? Would the next best diagnostic step be simply disconnecting the endlinks on both sides and seeing if noise goes away? If so (dumb question), I assume I would disconnect at the bar? I've watched Farkle's endlink swap video so seems straightforward enough.

Thanks much
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      12-30-2021, 10:21 PM   #2
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IME top mount/camber plate noise is pretty clearly felt/heard from the top of the engine bay.

It's possible to have a loose enough end link to create noise, but not so loose that you easily feel it when going under the car like you did. This is because there can be load on the bar/end link even when the car is in the air. I would just grab the appropriate socket and tighten all the end link nuts first to see if any of them are loose. I think it'd be less likely that the bolts securing the end link brackets came loose (especially if you've never swapped the stock bar out).
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      12-31-2021, 09:43 AM   #3
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Quote:
Originally Posted by FaRKle! View Post
IME top mount/camber plate noise is pretty clearly felt/heard from the top of the engine bay.

It's possible to have a loose enough end link to create noise, but not so loose that you easily feel it when going under the car like you did. This is because there can be load on the bar/end link even when the car is in the air. I would just grab the appropriate socket and tighten all the end link nuts first to see if any of them are loose. I think it'd be less likely that the bolts securing the end link brackets came loose (especially if you've never swapped the stock bar out).
Thank you sir.... will give that a try
The sound itself is a bit tricky, at times I think it could be more from topside but honestly I'm not sure
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      12-31-2021, 02:02 PM   #4
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You can also disconnect the links from the sway bar and hang them out of the way with zip ties, then drive the car and see if the noise goes away.
If it does, that was your issue. If it doesn't it's something else.

Sway bar links can make a lot of noise and sound like something much larger when they go bad. They're like the squirrel in the woods that sounds like a deer.
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      01-04-2022, 07:33 PM   #5
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Is it more pronounced on the drivers side?

I had a similar thing happen when I first fitted my MSS springs (Which are height adjustable). Seemed more pronounced on the front right (Drivers side here in AUS).

Under a hard bump (only at higher speed - usually a pothole or something like that), it was hitting the bump stop, raising the car a bit seemed to fix it.
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      01-05-2022, 07:42 AM   #6
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Quote:
Originally Posted by bloke79 View Post
Is it more pronounced on the drivers side?

I had a similar thing happen when I first fitted my MSS springs (Which are height adjustable). Seemed more pronounced on the front right (Drivers side here in AUS).

Under a hard bump (only at higher speed - usually a pothole or something like that), it was hitting the bump stop, raising the car a bit seemed to fix it.
Thanks... Honestly it's hard to tell. I considered that possibility, a valid concern in particular since FaRKle!'s youtube vid on the Vorshlag camber plates taught me something new: that the increased thickness of the plate design forces the bumpstop to sit closer to the damper than it otherwise would (remediable with the cool trick of flipping the bumpstop upside down), therefore reducing damper travel further. My drop honestly is pretty mild, though. Also as I noted, the fact that at times (not all the time) I can feel something knocking/rattling at my feet makes me think it's something on the bottom end.

This past weekend when changing to winter tires I did snug up just the endlink bolts at the damper (they didn't seem loose), but no change in noise. When I have more time I'll take belly pan off so I can get at the bolts at the bar, and while I'm there be sure that all other arms are snug, and check the subframe bolts as well. May have to consider Racer20's steering gear clunk as well (though no noise noted when rapidly turning steering wheel back/forth with car stationary)
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      01-29-2022, 08:40 AM   #7
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Quote:
Originally Posted by jfritz27 View Post
Thanks... Honestly it's hard to tell. I considered that possibility, a valid concern in particular since FaRKle!'s youtube vid on the Vorshlag camber plates taught me something new: that the increased thickness of the plate design forces the bumpstop to sit closer to the damper than it otherwise would (remediable with the cool trick of flipping the bumpstop upside down), therefore reducing damper travel further. My drop honestly is pretty mild, though. Also as I noted, the fact that at times (not all the time) I can feel something knocking/rattling at my feet makes me think it's something on the bottom end.

This past weekend when changing to winter tires I did snug up just the endlink bolts at the damper (they didn't seem loose), but no change in noise. When I have more time I'll take belly pan off so I can get at the bolts at the bar, and while I'm there be sure that all other arms are snug, and check the subframe bolts as well. May have to consider Racer20's steering gear clunk as well (though no noise noted when rapidly turning steering wheel back/forth with car stationary)
I developed a similar issue with my ground control camber plates after hitting a pothole. There is a bearing inside most of these camber plates that can wear out. It will sound like a clunk when you have lateral weight transfer or going over bumps. I'm not sure of your camber plate design, but I would imagine there is a similar bearing. It's technically a wearable item, and in a street-driven car, might need to be replaced periodically.
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      01-29-2022, 04:34 PM   #8
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Quote:
Originally Posted by biofluke View Post
I developed a similar issue with my ground control camber plates after hitting a pothole. There is a bearing inside most of these camber plates that can wear out. It will sound like a clunk when you have lateral weight transfer or going over bumps. I'm not sure of your camber plate design, but I would imagine there is a similar bearing. It's technically a wearable item, and in a street-driven car, might need to be replaced periodically.
Yes, ultimately it may just be that... but they really haven't been on the car long, and the Vorshlags are supposed to be pretty stout (particularly if installed "correctly", which I believe they were).
Since previous post I tightened the steering gear a bit (probably less than most from what I've read), and perhaps slightly better but still there. I may go a little more. Subframe bolts seemed tight. Waiting on my front SPL endlinks; if that doesn't do it then it's probably the plate bearing
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