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Quiet knocking noise

Ive got out for a spin, and the hard left to right knocking has been largely removed. There now seems to be a very light creak/knock when going over undulations. For example reversing around a corner when one rear wheel gets raised. I wonder if that is the cross supports?

Cheers
 
Right - saga continues. I've been to the garage and the guy has worked on 996's since they launched. So... were both flummoxed. Any help would save me going insane....

Every nut and bolt tightend on both right and left. All black poly (new) and suspension (new) tighten including top mounts etc.

Certainly reduced the noise but not eliminated.

The noise is evident in lond sweeping corners, i.e round abouts - if you've just heard the knock turning right, it wont come back until you do a long left +30mph and hear the knock and vice versa.....

It's like a pendulum affect when it hits the knock....

The ball joint rubbers were suggested to be a little on the tired side, but plenty of life and zero movement.

The Anti-roll bar bushes are tired, and the bar is corroding a little.. question - what size do I buy - the bar on a vernier measures c. 18m

Don't suppose anyone has any ideas at all?

Thanks in advance
 
Right - I'm in need of help..... sorry again!

Just before it goes into the garage for a full overhaul, is there anything more I should check.

I have done the following;

- Tightened all bolts/nuts
- Installed new engine mounts
- Installed new ARB bushes with the same poly black series
- Tightened the sub-frame
- Tightened suspension and top mounts

For clarity - the car has only done c. 5k miles on brand new Bilstein suspension and new poly bushes all round.

The noise is still only present left to right, and only on long sweeping corners, not sharp left to right

Very grateful for any help at all!

Thanks
 
Well..... for those interested, it's now been with a garage for two days and they can't locate the issue 🤷‍♂️

They have isolated the knock to the rear near side but can't solve the issue....

Question regarding top mounts.... can I replace just the insert/sleeve to see if that helps, or do I need to renew the whole top mount?

Thanks
 
Well..... for those interested, it's now been with a garage for two days and they can't locate the issue 🤷‍♂️

They have isolated the knock to the rear near side but can't solve the issue....

Question regarding top mounts.... can I replace just the insert/sleeve to see if that helps, or do I need to renew the whole top mount?

Thanks
Gosh what a saga this has been!

Have the garage taken the car out for a test drive and replicated the issue?

Also did you have the old bushes pressed out and new polys pressed in for every single arm on the car? There’s a lot of them!
 
I don't really have anything to add, just letting you know you're not being ignored and we can all feel your pain.

It really does sound like a ball joint though.

Were they new arms you put the polybushes in?

What I'm getting at is, you have not put new bushes in a control arm or track arm with a ball joint that has gone?
 
1 question.... do you have wheel spacers fitted.... could this noise be wheel related rather than suspension or geometry....?
 
Also, don't think it is this, but check the 3 13mm nuts on the top of top mounts are tight.

Jack the car up and make sure the springs are tight too.

If suspension work has been done, just make sure all the compensation pads etc. have been put back in, if jacked up and the spring is loose you need to work out why.
 
Just read back through, If you haven't replaced the top mounts then you really need to do this next.


When you said you had done a refresh with Bilstein I presumed new top mounts would have gone on. They go all the time, OK less on the rear, but if they have not been done for a while I would say definitely do these.
 
agree with the above but it could also be the steering rack.

I have a knock / cluck on mine to investigate. its front left and only on 1st movement in the opposite direction to just going. Mines off to the garage start of next week.
 
Okay so update is the following;

After inspecting on the ramp, when they pull the car off and push it backwards, the knock replicates itself prominently.... Don't know if that gives any other indicators to what it might be....

All bolts have been re-torqued, including the sub-frames.

It's the rear near side, so not sure its steering?

The rear near side top mount is being removed tomorrow and being checked for play.

Any recommendations on what top-mount to replace it with..... if it is the top mount?

Thanks
 
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Yes, wheel spacers fitted, but they have been for a long time and the noise only just started, they say they are tight and no issues.... good thought though. They have also checked calipers, cv joints drive shafts.... lets just pray its the top mounts... I'm running out of money :ROFLMAO:
 
Gosh what a saga this has been!

Have the garage taken the car out for a test drive and replicated the issue?

Also did you have the old bushes pressed out and new polys pressed in for every single arm on the car? There’s a lot of them!
New bushes into old metal.......

They've taken it out a handful of times..... I hope letting it warm up :)

Noise is pinpointed to the rear near side wheel arch.... they have had hands, ears and eyes on the top mounts and promise no noise from them. But I've asked them to pull it off tomorrow and check for any signs of wear or play and then take it from there. If it isn't the top mounts then...... does anyone want a 996 c2?
 
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Not exhaust... and new engine mounts but thank you.

Worth mentioning that the garage have said that since tightening everything, the noise has got more prominent......?
 

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