Suspension Knock

[eightsixboy]

I have this really annoying knock in my front suspension/front engine area, its not on all bumps or on any constant, just randomly. The noise sounds like the swaybar is clunking on the body or something like that, I have checked and it is clearing everything.

This just started randomly a few weeks ago, I did a winton track day about a month ago and had no problems up there or when i got back so i dont thnk that has anything to do with it.

I have had a look at length a few times this week but cant find anything worng. I have checked the following

Swaybar links - drivers is rooted but the clunk is from the passeneger side and doesnt sound like a link, I would assume a swaybar balljoint link will have a less noticable knock.

Rack - fine has no play

Tie rods - no play

Balljoints - top and bottom fine, tight like a tiger

caster rods - have aftermarket with ball joints and they are fine

upper arms - brand new hard race items

Wheel bearing - feels tight

Engine and gearbox mounts - fine, no splits or tears

Lower contro arm - inner bushes feel fine

I grabbed the whole strut and couldnt feel anything loose or any play in anything, this has really got me stumped, i have been over the whole car pretty much and have found nothing wrong.

The annoying thing is that its random, I can go over bumpy roads and it feels nice and quite, then I might turn a corner with a slight bump and hear it.

Any ideas?

[simpletool]

Sway bar links have a very very noticeable knock/clunk. Check the joint at the top, it doesn't take much play at all to knock. You'd be amazed how loud a noise they make. I've had it a few times.

The fact you can go over bumpy roads and hear nothing then a slight corner will make it knock sounds EXACTLY like a sway bar link to me.

[eightsixboy]

Replaced both links on the weekend and the knock is still there

I noticed it happens more on suspension drop rather then compression, thinking it could be a coilover top mount or the coilover itself, there is pretty much nothing else it can be.

[eightsixboy]

Just went out to have a look again and found that the top nut wasnt super tight, tightened it a much as I could and took for a quick drive, seems all good now.

[Thelen]

Top nut of what?

Pics? (will help others )

[eightsixboy]

On the coilover itself, the centre nut on the strut top.

Ill wait till i actually drive home and see if it is gone 100%.

[Mr_RS4]

Am having the exact same issue in my stagea at the moment, just as you described it and I have just replaced EVERYTHING, new front driveshafts, ball joints, bushes, swaybar links, castor rods, tie rods etc... And like you said everything is tight and it doesn't do it all the time. Can be on the worst road and nothing (apart from usual rattles inside). But it also seems like it does it when the suspension drops not compresses. And its also on the passenger side too. Even checked my front subframe bolts and strut top bolts. Its driving me nuts. I'll try tightening the nuts that you did and see, did it end up fixing the noise. Its a pretty descent clunnk when it does happen though.

[Dohmar]

Replaced both links on the weekend and the knock is still there

I know this sounds absurd, but check the rear subframe. I was getting front knock due to worn subframe bushes - when I replaced them with whitelines, it went away... I have NFI how that works, but eh, the proof is in the pudding

-D