Weird rubbing mark with aftermarket front sway bar endlinks

[BishamontenZC6]

They visually look OK, I cannot see any tear. There's also no play in the ball joint. Still they are the only part of the front suspension that haven't been renewed and are 160'000km.

According to your experience, would it be possible that the subframes got a little bit loose with time even though they have never been touched ?

[Racecomp Engineering]

Originally Posted by BishamontenZC6

They visually look OK, I cannot see any tear. There's also no play in the ball joint. Still they are the only part of the front suspension that haven't been renewed and are 160'000km.

According to your experience, would it be possible that the subframes got a little bit loose with time even though they have never been touched ?

That seems unlikely. Is the noise loud? When does it occur? (potholes, all the time, etc)

- Andrew

[BishamontenZC6]

It's not loud and clear as a loose end link clunk would be, it's more like a muffled thump. You can hear it without music while driving but it's not obnoxious. It sounds a lot like this noise, posted a few years ago on the forum :

It only occurs at low speed (below 40km/h), when small bumps hit one side or general uneven pavement, particularly when those makes the car bounce from left to right quickly. It doesn't occur on speed bumps or at higher speed, when braking nor highway and spirited driving. Only city driving at low speed.

For peace of mind I checked again that the endlinks are tight today, they are ok. Also checked the top mount to struts nuts and they are tight. That's definitely weird.

[bdtbdtbdt]

It looks like maybe the very bottom of your shock is hitting the a-arm

[BishamontenZC6]

5 years with this car and it’s been nothing but pleasure, but that noise problem is really ruining it for me now. I don’t know what to do anymore, and unfortunately have no serious suspension specialist I could give the car to for check up in my surrounding. I’ve had my share of other quirks and problems with the car before but they all had logical and rewarding solutions, this one is just ridiculous and doesn’t make sense. It shouldn’t be anything too complex but the impossibility to solve it makes me want to drive the car straight into a lake and forget about it…

I found another video that shows more how it sounds inside the car when it happens (same road condition as the video, but lower speed in my case) :

[DarkPira7e]

Originally Posted by BishamontenZC6

5 years with this car and it’s been nothing but pleasure, but that noise problem is really ruining it for me now. makes me want to drive the car straight into a lake and forget about it…

I think you need to take a break if you're feeling this way about a noise after modifying your car. If it's a quirk that has no visible impact or detriment to the car, embrace that your car has something unique and continue to love it. It's still a cheap Japanese car, no need to take it to this level

[BishamontenZC6]

You're right that a break is needed, it's what I eventually did .

The thing is that this exact noise is not a quirk. I can live with crickets, DI or vacuum pump thumps as they are known quirks on that platform and I totally embraced them.

That suspension noise is not one of them. I've never had it on my first GT86, neither on my current BRZ that I had been driving for almost 2 years with it's current setup without any suspension noise before last month. If it had been there from the moment I installed the coilovers I would agree with everything you said, but it's not the case.

On top of that, I've been daily driving sports and modified cars for the last 25 years, 86's platforms for 8 years and my current one for 5 years, so it's not exactly that I'm lacking XP in that field.

It's true that so far there is no obvious sign that it might have an effect on the handling nor safety of the car, but as long as it's not proven it's difficult to take it for granted and I'm not great at gambling when it comes to safety. For me, unusual noise means something isn't right, cheap platform or not.

Nevertheless, I had some time during the holidays so I went all over it again and did the following for front and rear :

• Checked the endlinks again and made sure they are tight - OK
• Checked that all the nuts and bolts are tight to spec - OK
• Checked that the top nuts are tight - OK
• Checked that all ball joints are OK with no play - OK
• Checked that every bushings are OK - OK

What's has been replaced :

• Front endlinks (Aftermarket)
• Front sway bar bushings (OEM)
• Rear endlinks (OEM)
• Rear sway bar bushings, mount and bolts (OEM)

I also disconnected the endlinks at the front to figure out if noise was still occuring with the sway bar disconnected : it did. I can therefore definitely state that endlinks are not the culprit and will finally leave them in peace from now on.

Based on that, I really don't know. The only idea I'm having left is that those noises would be caused by the near 0°c we are having where I live since a few weeks. They started to appear mostly after I replaced the front sway bar bushings (OEM), which is also when it started to get colder. So maybe the new sway bar bushings (probably firmer than the 160k old ones), with very cold temperature generate more noise with the coilovers, that could themselves be clunkier in the cold. Problem is there's no way to know for good until temperatures go back up. I don't know what the chassis specialist around here think about this.