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Suspension and Chassis Knocking sound while driving over bumps / steering

Bu11eT

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Jun 30, 2018
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Hi guys,

so as some of you may know I've got the ST 20/20 springs.
Since they've been installed I noticed two things:

1. A sound when standing still and steering (Knocking-like sound)
I am just sitting in the car at a standstill and I am steering half way to the left and afterwards half way to the right.
The outcome is this sound: LINK TO SOUNDFILE

2. A sound while driving over speed bumps or a bumpy road in general (squeaky-like sound)
When driving over speed bumps I get another weird sound. I sounds as if something is not attached tightly to the car.
Not only does it happen when driving over speed bumps but also when I am pulling into my driveway (sound comes up as soon as the tires hit the small curbstone)
This is the sound: LINK TO SOUNDFILE

It should be noted, that the sound is only coming from the left front side of the car, neither the right front or the rear produce a sound.
My personal hypothesis is, that its the strut bearing. But I am by no means an expert so I also visited Hyundai as well as my local mechanic and both said they are not able to diagnose it without disassembling half the stuff sitting in the front left wheel well.

The Hyundai mechanic told me he re-tightened all the screws under the car and in the engine bay and he confirmed to me that the sound seems to be coming from the front left side of the car.

So before starting the disassembly-process I wanted to get an opinion from you guys, if some of you experienced a similar sound in their cars?
Also, if some of you have the part numbers for the left front suspension components, that would be of great help!


Thanks for your help!
 

Davo01

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That knock sounds like steering rack to me - I assume it’s not front left (drivers side). Heatshield rubbing on the columns is a creek or groan, not a knock.

No idea about the squeak though.
 
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Bu11eT

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Davo01

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Jan 28, 2019
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South Australia
I've seen that post:D however I am not sure if this issue fits my description as mine always does it - in warmed up and cold condition. And it's always happening at the same steering angle. Also, the sound does not appear when the car is on a lift (no load on the suspension).
Cool... but my issue was the heatshield - always mage the creek, not knock, hot or cold. And at any angle - a constant creek. Maybe I’m wrong - you could be lucky :)
 
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Davo01

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Jan 28, 2019
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Doesn't sound like a heat shield. It's coming from the bottom, front left, for sure. There's no heat shield there. It's sounds more suspension related to me.
I was referring to the stationary knock when turning the steering wheel. The first video when the phone is placed in the drivers ie right hand side, foot well. That’s where the rack and heatheild is.

Not the squeak when driving - no idea where that’s coming from other than the Bu11eT places the phone on the left side of the cabin so I’ll take his word for it ;-)
 
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Davo01

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Jan 28, 2019
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So drivers side. Defo rack and shield there.

This is why I hate referring to left and right. Drivers and passengers side is never wrong lol
 

R Veloster N

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Mar 5, 2019
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I wondering if this particular suspension knock isn't an issue with how they reinstalled the front shock struts. I've heard this type of knock, when the shock strut mounts have been loosened and reinstall incorrectly.

It will make a distinct pop or knock, when the wheel is turned setting still, moving or going over rough or bumpy roads. It sounds like it comes from the underside, on which strut was re-installed incorrectly.

I listened to @Bu11eT 's sound file again and it sounds just like what I've experienced and heard numerous times when they aren't set in the mount correctly.

Being the front struts have to be removed from the rack, I'd say it's a good bet the strut wasn't seated in the mount correctly. Especially, if the rotated the strut either way in the mounts. I've even done it myself on occasion and had to remove and reinstall to make it quit. I can also happen if the strut tower or shock mounts are just loosened then not making sure they are reseated.

Sorry, I didn't think or mention this sooner but it sounds exactly like what is in the sound/video file. I remembered the sound, as my neighbor was replacing his strut just yesterday. Oh well, the mind is not quite as sharp or quick as it used to be.:p

@Bu11eT; Have the dealer check the struts tower mounts for tightness, along with the strut mounting points, making sure they are properly installed and seated in the strut tower mounts.
 
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Bu11eT

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I wondering if this particular suspension knock isn't an issue with how they reinstalled the front shock struts. I've heard this type of knock, when the shock strut mounts have been loosened and reinstall incorrectly.

It will make a distinct pop or knock, when the wheel is turned setting still, moving or going over rough or bumpy roads. It sounds like it comes from the underside, on which strut was re-installed incorrectly.

I listened to @Bu11eT 's sound file again and it sounds just like what I've experienced and heard numerous times when they aren't set in the mount correctly.

Being the front struts have to be removed from the rack, I'd say it's a good bet the strut wasn't seated in the mount correctly. Especially, if the rotated the strut either way in the mounts. I've even done it myself on occasion and had to remove and reinstall to make it quit.

Thanks for the tip! @R Veloster N ! My current way forward is to have them remove the springs and to refit it again. Just to make sure it has nothing to do with a false installation process. If that doesn't help I am gonna revert back to stock springs and check if the sound disappeared. If that doesn't help either, I guess I have to get new strut bearings.

One step after another, its an emotional up and down with all the tips I am getting - one day I hope for an easy fix next day someone suggest some really expensive actions o_O
 
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R Veloster N

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That would be on Hyundai, as the strut bearings are a warranted item. The springs could have been rotated out of place as well and is contributing to the knocking noise.
 
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Bu11eT

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That would be on Hyundai, as the strut bearings are a warranted item. The springs could have been rotated out of place as well and is contributing to the knocking noise.
that's why I am trying to check everything else before the strut bearings.
As my springs are aftermarket ones, I don't think my strut bearings will be covered under warranty by Hyundai.

Right now I am really hoping its something trivial and easy to fix. Your comment gives me hope :D
 
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R Veloster N

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The aftermarket springs themselves won't kill warranty on the strut bearing.

I betting it's the springs as it was on my neighbors. If they get rotated out of place and everything is tightened, they'll make a pop/knock when setting still and moving the steering wheel lock to lock.

The spring will actually rotate as the steering wheel is moved if it's not properly seated in the strut spring mount.
 
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Bu11eT

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The aftermarket springs themselves won't kill warranty on the strut bearing.

I betting it's the springs as it was on my neighbors. If they get rotated out of place and everything is tightened, they'll make a pop/knock when setting still and moving the steering wheel lock to lock.

The spring will actually rotate as the steering wheel is moved if it's not properly seated in the strut spring mount.

thanks for the tip with the warranty - didnt know that. Next weekend I am gonna visit my mechanic, lets see what happens if he refits the springs!
 
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