Coilovers binding at low speed, hard turns - theories on why, how to fix? (PSS10)

[millerrh]

I recently had some Bilstein PSS10's installed. Now, whenever I am doing low-speed, hard turns (like when you are pulling into a parking spot), I am noticing some really horrible noises. It sounds like the springs are being caught and then releasing with loud "pong" and "boing" sounds. From the research I've done, it seems like this is probably caused by the coils touching and then binding during turning maneuvers.

Wanted to poll AZ to see if anyone has any other theories and/or fixes. Pics below and some things I've tried out.

Here you can see that in the resting state, there are some coils touching. On further examination, you can see some wear in the blue coating where it looks like there is rubbing going on.



One thought I had was to lower the spring perch more. This would in theory spread out these coils and prevent them from touching as much. I did this slightly and am now within Bilstein's published specs in their manual (215mm from bottom of the shock), but it is still making these noises. Also, I am now lower than I really want to be. My target is just a hair over 26" fender-to-ground. I have heard of people running these coils at closer to factory height without issues, so being lower than 26" as I am now seems like it should work. I'd still like to raise them up more if possible. It's hard for me to believe that Bilstein's highest published spec is lower than 26" fender to ground (based on the manual). H&R OEs are ~26" FTG as a reference which are a 1.2" (30.5mm) drop. You'd think they would give you more wiggle room in height adjustability. And even their website says that this lowers the S4 10-30mm. So I think those published specs on the website are incorrect, unless I am doing something wrong.

Here are the images of measuring the correct height of the spring perch as far as I can tell. Keep in mind that 215mm = slightly lower than 26" fender to ground for me. I would like to fix this binding issue. So if you know what might be causing it or how to fix it, I would love to hear your ideas! This is not something I expected from a top of the line coilover. So I'm hoping it's just something stupid with the install or something easy to fix. I do plan on taking back to the shop for them to look at it, but I want to be prepared with suggestions for them to examine, or hopefully be able to fix myself. Many thanks to all who can help, you guys have been a great resource!





Manual diagram telling you about acceptable lowering adjustment heights.

[will13k7]

I'm at 25 3/4 inches FTG, mine sound like they bind/unbind when pulling in/out of my driveway also. Not every time though. I'm kind-of used to performance suspension parts making noise, it has on all of my previous cars.

[wwhan]

You might check to see, if the bolts with the rubber bushings were torqued at the correct new ride height.

I had my PSS10s adjusted to about 16mm lower than stock (before I put on the KW street comfort) & it did look like the PSS10 center coils were touching. Setting the dampers firmer, will make it less likely to bottom spring compression on sudden suspension compresion impulses.

What do you have the dampers adjusted to? 1 -10 ?

The PSS10 coilover springs are progressive & the inner coils have less space than the outer coils.

The PSS10 has a large height adjustment range (much better than the KW).

The same coilover kit is specified for all the B8 years and models (othjer than Avant). There is well over 200lbs difference on the models and weight distribution is different. None of the coilover companies consider this relevant to the rated height, which is totally wrong. Some of these have Sport suspension some do not.

2008-2013 Audi A4 Base 2.0l L4 FWD, Sedan
2008-2009 Audi A4 Quattro Base 2.0l L4 AWD, Sedan
2008-2009 Audi A4 Quattro Base 3.2l V6 AWD, Sedan
2010-2013 Audi A4 Quattro Base 2.0l L4 AWD, Sedan
2010-2013 Audi A5 Cabriolet 2.0l L4 FWD, Convertible
2008-2013 Audi A5 Quattro Base 3.2l V6 AWD, Coupe
2010-2013 Audi A5 Quattro Cabriolet 2.0l L4 AWD, Convertible
2008-2013 Audi S4 Base 4.2l V8 AWD, Sedan
2008-2013 Audi S5 Base 4.2l V8 AWD, Coupe
2010-2013 Audi S5 Cabriolet 3.0l V6 AWD, Convertible

[millerrh]

You might check to see, if the bolts with the rubber bushings were torqued at the correct new ride height.

I had my PSS10s adjusted to about 16mm lower than stock (before I put on the KW street comfort) & it did look like the PSS10 center coils were touching. Setting the dampers firmer, will make it less likely to bottom spring compression on sudden suspension compresion impulses.

What do you have the dampers adjusted to? 1 -10 ?

The PSS10 coilover springs are progressive & the inner coils have less space than the outer coils.

The PSS10 has a large height adjustment range (much better than the KW).

The same coilover kit is specified for all the B8 years and models (othjer than Avant). There is well over 200lbs difference on the models and weight distribution is different. None of the coilover companies consider this relevant to the rated height, which is totally wrong. Some of these have Sport suspension some do not.

2008-2013 Audi A4 Base 2.0l L4 FWD, Sedan
2008-2009 Audi A4 Quattro Base 2.0l L4 AWD, Sedan
2008-2009 Audi A4 Quattro Base 3.2l V6 AWD, Sedan
2010-2013 Audi A4 Quattro Base 2.0l L4 AWD, Sedan
2010-2013 Audi A5 Cabriolet 2.0l L4 FWD, Convertible
2008-2013 Audi A5 Quattro Base 3.2l V6 AWD, Coupe
2010-2013 Audi A5 Quattro Cabriolet 2.0l L4 AWD, Convertible
2008-2013 Audi S4 Base 4.2l V8 AWD, Sedan
2008-2013 Audi S5 Base 4.2l V8 AWD, Coupe
2010-2013 Audi S5 Cabriolet 3.0l V6 AWD, Convertible

I've got them set to 5 now. Had them at 6 last week. Didn't seem to matter.

Also, if you look at their website, for A4, the range is 30mm - 50mm and for S4 it is 10mm - 30mm. That makes me think they are taking into account sport suspension and weight on the website. But when looking at the image in the manual, it seems to say something different since the 215mm is more like 30mm.

When you had them set to 16mm, did you have any binding sounds?

Edit: which bolts with the rubber bushings are you referring to? If you change the ride height, do you need to re-torque something? This could be an issue as I did raise it up from where they set it initially (way too slammed).

[westwest888]

They bind. I had them on my 3 series. You just deal with it or go stock.

[Hsiang]

I'm having the same issue with my KW v3s... I hate it when it does that... anyone know how to fix this?

[jran76]

I had similar issues with my ST's, and decided to go with the Stasis/Ohlins coilovers instead. They use a linear spring, and do not have these types of issues (along with many other benefits from my perspective).

My suggestions are as follows:
1. Make sure all your hardware was tightened at your ride height (at least where bushings and such are concerned)
2. Raise the car, and go to stiffer settings if possible to keep as much space between the coils as possible
3. See if it is possible to add some type of sleeve to the coils to eliminate some of the noise

[wwhan]

....When you had them set to 16mm, did you have any binding sounds?

Edit: which bolts with the rubber bushings are you referring to? If you change the ride height, do you need to re-torque something? This could be an issue as I did raise it up from where they set it initially (way too slammed).

I did not notice binding with the PSS10s on, but the inner coils did touch at some point in usage (marks where they had touched).

On re-torque of the rubber bushings at new ride height, see thread: http://www.audizine.com/forum/showth...orque+bushings

[Over9000]

The noises that you are hearing are definitely spring bind, and it doesn't appear that there is anything wrong with your install. I went through two full re-installs and a lot of tinkering (all sorts of ride heights, damper settings) to figure out why half the spring was essentially useless and whether that was indeed what was making those noises (even threw chassis ears in there). I have no idea how/why Bilstein would overlook something like that many turns of a spring being in contact under static load, other than the fact that these shocks are intended to fit about a million vehicles, as wwhan pointed out.

I don't know how long you've had them on, but mine have since stopped doing it. The only time I get any more spring bind noise is for about half a day after it's been jacked up/on a lift, until everything gets itself settled in again. I don't remember exactly how long it took for it to initially quiet down...maybe a month or two. They somehow still perform wonderfully, despite having four turns of the spring compressed - maybe just due to the magical Nürburgring stickers on there (100hp bonus each, btw) - but I do have concerns about wearing through that coating in the northeast winter.

[PitchS4]

My old PSS9s on my B6 lost their coating as well but held up to 80k miles and a few jersey winters (before I sold it no idea how much longer they lasted). I wouldn't worry about that.

If anyone wants to trade my HR OEs + cash for their PSS10s LMK. OEs don't bind :D

[Over9000]

My old PSS9s on my B6 lost their coating as well but held up to 80k miles and a few jersey winters (before I sold it no idea how much longer they lasted). I wouldn't worry about that.

That's good to hear. Thanks, Mike.

[millerrh]

I did not notice binding with the PSS10s on, but the inner coils did touch at some point in usage (marks where they had touched).

On re-torque of the rubber bushings at new ride height, see thread: http://www.audizine.com/forum/showth...orque+bushings

I had similar issues with my ST's, and decided to go with the Stasis/Ohlins coilovers instead. They use a linear spring, and do not have these types of issues (along with many other benefits from my perspective).

My suggestions are as follows:
1. Make sure all your hardware was tightened at your ride height (at least where bushings and such are concerned)
2. Raise the car, and go to stiffer settings if possible to keep as much space between the coils as possible
3. See if it is possible to add some type of sleeve to the coils to eliminate some of the noise

Assuming my installer did this when first installing them (not 100% sure they did), would you need to loosen and re-tighten even when doing small height adjustments? One thing I did right away was raise the car up from where they set it. It was way too slammed and I couldn't even make it over some speed bumps in my neighborhood. To do that, I jacked the car up, raised the collars, and that's it. Is that OK? Are the bushings in close enough position at that point where you can make smaller adjustments? Which bushings specifically is this referring to? The ones on the upper control arms, both sides?

I don't remember it making noises driving home from the shop. But I didn't drive them around very much like that either. So not sure if it was present or not. I suspect if not, it was because they were so low that the springs were more spread apart.

Regarding your suggestion to raise the car to add space, my assumption is that raising the car actually makes this worse. If you look at the images I posted above, the top of the spring is static, the bottom of the spring can move along the threaded shock body. If you raise the spring perch collar, it will compress the spring more than if you lower the perch collar in that unloaded state. Now once the weight of the car goes on it, who knows. Maybe it's a minuscule difference. But that's why I thought lowering it more would fix this, not raising it more. Am I wrong about this assumption?

Edit: Now that I think about it, maybe the spring is always the same, but raising and lowering the perch simply offsets it by a different amount...now I'm not sure about it. Can anyone clarify if you're actually putting more pre-load in the spring by raising the collars?

[jran76]

Assuming my installer did this when first installing them (not 100% sure they did), would you need to loosen and re-tighten even when doing small height adjustments? One thing I did right away was raise the car up from where they set it. It was way too slammed and I couldn't even make it over some speed bumps in my neighborhood. To do that, I jacked the car up, raised the collars, and that's it. Is that OK? Are the bushings in close enough position at that point where you can make smaller adjustments? Which bushings specifically is this referring to? The ones on the upper control arms, both sides?

I don't remember it making noises driving home from the shop. But I didn't drive them around very much like that either. So not sure if it was present or not. I suspect if not, it was because they were so low that the springs were more spread apart.

Regarding your suggestion to raise the car to add space, my assumption is that raising the car actually makes this worse. If you look at the images I posted above, the top of the spring is static, the bottom of the spring can move along the threaded shock body. If you raise the spring perch collar, it will compress the spring more than if you lower the perch collar in that unloaded state. Now once the weight of the car goes on it, who knows. Maybe it's a minuscule difference. But that's why I thought lowering it more would fix this, not raising it more. Am I wrong about this assumption?

Edit: Now that I think about it, maybe the spring is always the same, but raising and lowering the perch simply offsets it by a different amount...now I'm not sure about it. Can anyone clarify if you're actually putting more pre-load in the spring by raising the collars?

Sorry, meant lower. Changing the height or perch position does change the load on the spring.

If you make a small height adjustment, the bushings should be fine. There is a lot of play to compensate for suspension movement to begin with.

[drob23]

Dumb question, but is this sound separate from "clunk" sounds you would normally associate with metal on metal contact? I have some noise in the right rear when going over speed bumps at low speed. Not sure if it's loose bolts or need for more grease on the EC sway bar bushings. It's annoying but I'll deal with it once things warm up.

[IanCH]

Clunking is normally caused by improper tightening of the shock piston to the upper carrier IIRC

[millerrh]

My sound definitely is more of a springy, non metal-on-metal sound coming from the front. Although I may have also noticed that a couple of times in the rear. Not nearly as loud or often as this binding sound.

[wwhan]

My sound definitely is more of a springy, non metal-on-metal sound coming from the front. Although I may have also noticed that a couple of times in the rear. Not nearly as loud or often as this binding sound.

Check the sway bar end links. Torque them down (at ride height, unless they are EC links) and use blue loctite.

[d.p]

I thought you posted in the B8 section as well and people there said to use some kind of spring wrap to solve the noise issue.

Specifically these: http://www.optionsauto.com/prodinfo....IN-SPR02-G1497

[AndyLien79]

My sound definitely is more of a springy, non metal-on-metal sound coming from the front. Although I may have also noticed that a couple of times in the rear. Not nearly as loud or often as this binding sound.

Do you like yours set at 5 or 6? which one is most comfortable with the least bounce?

[millerrh]

I thought you posted in the B8 section as well and people there said to use some kind of spring wrap to solve the noise issue.

Specifically these: http://www.optionsauto.com/prodinfo....IN-SPR02-G1497

Yep, I asked a similar question in another guy's thread in the A4 section. Just wanting to post this as well in the S4 forum with it's own thread subject to give it some attention in case S4 folks don't look at the other forums much.

Will definitely try something like that if I can't find other ways to fix it, but trying to eliminate any install/setup issues/variables first. I'd rather fix the issue than symptoms of the issue if it's possible. I still am not 100% convinced that this is a universal issue with PSS10 folks otherwise you'd probably hear a lot more complaining about it.

If it's by design and silencers are the only way out, then so be it, I will certainly try those or some other spring wrap. Also, if anyone has had success with a spring silencer wrap of some sort, please post which one. I am interested in these sorts of fixes and looking for the best option. Those TEIN ones seem to only surround one coil. But I've got 4 touching on each side. They also are targeting coil slap, not bind. So not sure if it's the perfect choice.

Also seems like something like that might take a beating and not last a long time. Which is another reason I'm hoping to find a different solution.

I'm still playing around with settings on the dampers. Gone back and forth between 5 and 6. I might experiment with 4 and 7 to see a bigger difference. So far, it seems like 5 is bouncier and 6 is harsher. I want to see if 4 is even bouncier or if 7 is too harsh before I settle on something.

[IanCH]

have you tried spraying the spring with a dry lubricant (silicone) while it is decompressed?

[millerrh]

have you tried spraying the spring with a dry lubricant (silicone) while it is decompressed?

Have not. But that's one thing my mechanic mentioned was lubricating it. So I may try that.

Back to my question about whether raising the perch further compresses the spring. Thinking about it more, I'm not sure it does.

Here's my thought process/logic, please tell me if I'm wrong.

• The upper strut mount/top of shock piston is fixed to the car/frame.
• The bottom of the shock is fixed to the control arm/wheel hub assembly. But this bottom mount is free to move as you go over bumps, etc. This is where the shock piston travels in and out of the shock body.
• When the weight of the car is supported by the spring, the length of the compressed spring is what dictates the position of both top and bottom mounts relative to each other and the position of the piston at a resting state.
• The weight of the car on the spring should compress it the same regardless of height.
• By changing the perch ring height on the bottom of the shock you are simply raising and lowering the bottom of the spring in the compressed state.
• And by changing the bottom location of the spring upward for instance, you are also moving the top mount upward by an equal amount since the compressed spring is the same length. Therefore the piston is further up within the shock body and your car is higher, but the spring is still the same compressed length as it was at the lower location and not any more prone to extra compression.

It seems to me like in all cases, the spring is the same distance from top to bottom once compressed by the weight of the car, so what you are really doing when changing heights is changing where the piston is within the shock body. My guess is the limits imposed by Bilstein are probably more due to shock travel so you don't bottom the shock out and not spring compression.

Based on that, it seems ride height isn't a factor in coil binding unless I have something wrong. Please feel free to flame if so. I know I have heard that it is before, but I'm not sure why now.

[IanCH]

You are correct, the spring is always the same compressed length static under the weight of the car on flat ground.

[Akatsuki...]

I have PSS10s and no issue.. even in the winter. Fronts are about 1 finger gap.. rears no finger gap.
Front 7 rear 4.

[d.p]

I have PSS10s and no issue.. even in the winter. Fronts are about 1 finger gap.. rears no finger gap.
Front 7 rear 4.

^ Reverse rake? Post a pic my man.

[westwest888]

^ Reverse rake? Post a pic my man.

The rebound setting of the damper has NOTHING to do with the ride height. Further, if you are setting a front engined car up properly the front arches will be higher off the ground at rest than the rear arches. Look at any well balanced BMW. After corner balance, each corner will be at a slightly different height imperceptible to the eye.

When I see a car with the front slammed and the rear riding high I try to avoid it.

[d.p]

The rebound setting of the damper has NOTHING to do with the ride height. Further, if you are setting a front engined car up properly the front arches will be higher off the ground at rest than the rear arches. Look at any well balanced BMW. After corner balance, each corner will be at a slightly different height imperceptible to the eye.

I never said it did. He said one finger gap in the front and none in the rear and that to me would mean the front is sitting higher than the rear.

[[email protected]]

Wow, the spring should not be bound up like that. Is that with no weight on the front suspension?

Spring bind is not normal and should not be expected on coilover kits or lowering springs. You should not see windings stacked like that, especially at full droop, if that's what that is.

Cheers,

[Akatsuki...]

^ Reverse rake? Post a pic my man.

Corner Balance :p

[millerrh]

Wow, the spring should not be bound up like that. Is that with no weight on the front suspension?

Spring bind is not normal and should not be expected on coilover kits or lowering springs. You should not see windings stacked like that, especially at full droop, if that's what that is.

Cheers,

That pic is with the weight on the springs (fed my phone in the wheel well to take the pic). When I jack it up and remove weight from the suspension, those coils that touch spread apart slightly, but are still obviously close together.

Here you can see (someone else's pic) how close the middle coils are at free length. A little compression pushes them right together.

[jran76]

Have you tried to call Bilstein to see what advice they have?

[IanCH]

Do you have the rear springs in the front?.....

[millerrh]

Have you tried to call Bilstein to see what advice they have?

No, but it's a good idea. Their website tends to push you off to their distributors, but I may give it a try anyway.

Do you have the rear springs in the front?.....

Nope, that would be almost impossible I think considering the different sizes between them.

[IanCH]

No, but it's a good idea. Their website tends to push you off to their distributors, but I may give it a try anyway.



Nope, that would be almost impossible I think considering the different sizes between them.

Okay, I'm not trying to call you out, just was trying to think how it could be that off given the above responses...

[Sgibb16]

Do you have the rear springs in the front?.....

Nope, that would be almost impossible I think considering the different sizes between them.

TBH it kind of looks like you have rear springs up front. Its weird but different pics of pss10 show different springs

I feel like the fronts should look more like these



But then again I see threads like this
http://www.audizine.com/forum/showth...d-2010-Audi-S4


I dont have PSS10's but the springs on my front coils look much more like the top pics

[millerrh]

Those pics you linked to are from a different system.

Straight from Bilstein's website:



Not sure why they did it like that for our cars, but it seems to be part of the design that they touch as far as I can see. You can even see how close they are in that unloaded state in that picture you posted at the end.

[[email protected]]

The springs are progressive and what I would expect with the kit is that the center section would stay fairly similar spaced when the weight of the car was put on the spring and the top and bottom windings would give until ride height. Then initially the ends windings would be what compresses over small bumps, gentle loading and then when you hit a really big bump or really start cornering, braking, etc the center of the spring would start to compress.

At standard ride height coils should _not_ be stacked up touching each other. This means that when you are loading that suspension you basically have a solid block in the middle of it, zero travel in that portion if it's solid at ride height, so only those small windings are the top and bottom have any travel. I have seen this before on lesser costly lowering springs and lower level coilover kits, but really spring bind is not normal at ride height or in normal operating range of the suspension. Progressive springs really do have this problem while properly rated linear rate springs do not.

Cheers,

[millerrh]

I just got off the phone with customer support at Bilstein. Overall, not incredibly helpful in diagnosing the problem, but he did help to clarify a few things.

First of all, he says the progressive springs behave opposite what Alex is saying, that the closer coils are the softer ones and should compress to where they touch under resting height. So he seems to confirm that the way I have it installed is correct.

According to him and his warranty dept., they haven't had much report of coil bind. But he did also suggest it might be the coil rotating on the perch/seat is what is causing the bind.

He seemed to think there was much more room for adjustment than the 215mm they give in the manual. That this shock is used on so many models that they simply calculate the height based on weight. But if you have a heavier car, it will sit lower at the same perch height than a lighter car. So raising it up more didn't seem to be an issue in his mind. And he thought it was a typo in the manual actually. That the heavier car should go up to 225mm, not 215mm.

One interesting thing is some spring systems they make come with a silencer material on them. Check out this coilover for the TT. It's got a clear silencer tube on it already.

[IanCH]

Yeah, alex does have it backwards. Anyone who has ever used a spring compressor on progressive rate springs knows that the tighter coils compress first.

Did you lube it yet? my guess is that it will solve the noise.

[millerrh]

Not yet. Got an appt Monday morning to hoist it up and get a better look. Will try living and trying to find some suitable coil wrap.