[johnung]

Question for guys experienced with adjustable end links. My suspension was handling great especially since I replaced the rubber bits with new OEM rubber a month ago. Finished that off with a fresh alignment to stock specs.

F30 335i XDrive with Koni SA’s, Eibach springs, H&R sway bars, VAC control arms, all that I’ve had for a while.

Then I added KC Design adjustable sway bar end links. I assumed that it would feel the same or might even ride more comfortably with them adjusted perfectly neutral.

But now with the new end links I’ve noticed a distinct dull thump when I go over minor road imperfections and small road seams. (Nothing that would contact bump stops which were trimmed.) It’s similar in sound and feel to major thumping transmitted to the cabin when a car has a flat tire. Obviously no where near as bad as a flat but the closest way I could think of to describe it.

I was told that they were installed using the same method as in FaRKle’s video below.

https://youtu.be/Q_sBjb82glc?si=WoPYtPbLX5zYdFeJ

Was I correct in assuming that end links adjusted in a neutral position shouldn’t be felt going straight down the road? I’m assuming that the thumping is some sort of adjustment issue. Any help is appreciated. Thanks

[Polo08816]

Originally Posted by johnung

Question for guys experienced with adjustable end links. My suspension was handling great especially since I replaced the rubber bits with new OEM rubber a month ago. Finished that off with a fresh alignment to stock specs.

F30 335i XDrive with Koni SA’s, Eibach springs, H&R sway bars, VAC control arms, all that I’ve had for a while.

Then I added KC Design adjustable sway bar end links. I assumed that it would feel the same or might even ride more comfortably with them adjusted perfectly neutral.

But now with the new end links I’ve noticed a distinct dull thump when I go over minor road imperfections and small road seams. (Nothing that would contact bump stops which were trimmed.) It’s similar in sound and feel to major thumping transmitted to the cabin when a car has a flat tire. Obviously no where near as bad as a flat but the closest way I could think of to describe it.

I was told that they were installed using the same method as in FaRKle’s video below.

https://youtu.be/Q_sBjb82glc?si=WoPYtPbLX5zYdFeJ

Was I correct in assuming that end links adjusted in a neutral position shouldn’t be felt going straight down the road? I’m assuming that the thumping is some sort of adjustment issue. Any help is appreciated. Thanks

I would think the thumping is more of an issue with the ball joints of the sway bar end links.

I would disconnect them and drive at slower speeds to see if you still experience that thumping. If so, then maybe it's not the end links.

[johnung]

Originally Posted by Polo08816

I would think the thumping is more of an issue with the ball joints of the sway bar end links.

I would disconnect them and drive at slower speeds to see if you still experience that thumping. If so, then maybe it's not the end links.

But the sway bars themselves don’t come with ball joints. So it’s not like I have a worn out part causing the thumping. The ball joints are brand new and an integral part of the adjustable end links. See photo.

So are you saying that the ball joints of the new adjustable end links may be harsher compared to ball joints on stock end links, so they are introducing the thumping? Now that would suck. I’m hoping it’s an adjustment issue.

[Polo08816]

Originally Posted by johnung

But the sway bars themselves don’t come with ball joints. So it’s not like I have a worn out part causing the thumping. The ball joints are brand new and an integral part of the adjustable end links. See photo.

So are you saying that the ball joints of the new adjustable end links may be harsher compared to ball joints on stock end links, so they are introducing the thumping? Now that would suck. I’m hoping it’s an adjustment issue.

The quality of aftermarket (premium) parts these days is suspect. Perhaps there was a machining issue with one of the ball joint and the tolerances increased to the point where they allow motion (or in this case, thumping).

It's just a guess. You can disconnect the sway bar end links and drive around to see if the noise disappears. If so, chances are its the sway bar end links.

[johnung]

Originally Posted by Polo08816

The quality of aftermarket (premium) parts these days is suspect. Perhaps there was a machining issue with one of the ball joint and the tolerances increased to the point where they allow motion (or in this case, thumping).

It's just a guess. You can disconnect the sway bar end links and drive around to see if the noise disappears. If so, chances are its the sway bar end links.

Thanks for the suggestion. But I already know that it has something to do with the end links because the thumping began when they were installed. I’m trying to figure out if this is normal for this particular aftermarket part, if it needs adjustment or if it’s something else having to do with it.

[Polo08816]

Originally Posted by johnung

Thanks for the suggestion. But I already know that it has something to do with the end links because the thumping began when they were installed. I’m trying to figure out if this is normal for this particular aftermarket part, if it needs adjustment or if it’s something else having to do with it.

My guess is that adjustment "may" mitigate how often it thumps particularly if there's greater tension or compression applied to it (via length adjustment). Basically, greater pre-load.

However, I'm of the belief that there's "thumping" because there's play in the end link ball joints. This is likely to be a manufacturing defect.

I was going to comment about using the factory sway bar end links but realized your car is xDrive. For RWD cars, unless your suspension is 10mm lower than the M Sport/Sport suspension, you can continue to use your original sway bar end links. The M Performance Suspension kit is 10mm lower than the M Sport / Sport suspension and you can use the factory end links with that setup.

[weehe126]

Any update on this? I'm looking to get the same adjustable end links.

[johnung]

Originally Posted by weehe126

Any update on this? I'm looking to get the same adjustable end links.

Not yet. I’m juggling several projects right now. I also want to drive on them some more to see if they soften up. My current thoughts are:

1) Maybe they just need adjustment? I have great faith in the guys who installed them and they’ve offered to adjust. But I want to investigate other ideas first.

2) Could just be normal? But I haven’t heard from other guys who’ve installed adjustable end links to know if that’s the case.

3) Perhaps it is just this brand? I bought the KC Design’s because FaRKle! recommended them and did an installation video featuring them. He also said that unlike others on the market, the KCD’s had dust covers to prevent dirt from getting into the joint and ruining it. No others had dust covers, although Hotchkis now appears to have dust covers too, but at a much higher price.

ANYONE WHO HAS INSTALLED ADJUSTABLE END LINKS OF ANY BRAND, PLEASE CHIME IN. THANKS!

[weehe126]

I had adjustable links on my E90. They didn't make a sound. I can't remember the brand offhand. The stock links use ball joints just like the adjustable arms. So unless it was a machining issue, the ball joints shouldn't be causing this. I feel like you need to check the adjustment of them. Since they are already installed it would be easy.

[Polo08816]

Originally Posted by weehe126

I had adjustable links on my E90. They didn't make a sound. I can't remember the brand offhand. The stock links use ball joints just like the adjustable arms. So unless it was a machining issue, the ball joints shouldn't be causing this. I feel like you need to check the adjustment of them. Since they are already installed it would be easy.

It's pretty simple... you just take the wheel off and they are right there. You just the make the adjustment with simple hand tools...

[Polo08816]

Originally Posted by johnung

Not yet. I’m juggling several projects right now. I also want to drive on them some more to see if they soften up. My current thoughts are:

1) Maybe they just need adjustment? I have great faith in the guys who installed them and they’ve offered to adjust. But I want to investigate other ideas first.

2) Could just be normal? But I haven’t heard from other guys who’ve installed adjustable end links to know if that’s the case.

3) Perhaps it is just this brand? I bought the KC Design’s because FaRKle! recommended them and did an installation video featuring them. He also said that unlike others on the market, the KCD’s had dust covers to prevent dirt from getting into the joint and ruining it. No others had dust covers, although Hotchkis now appears to have dust covers too, but at a much higher price.

ANYONE WHO HAS INSTALLED ADJUSTABLE END LINKS OF ANY BRAND, PLEASE CHIME IN. THANKS!

If you're getting thumping and it's your endlinks, they're not going to "soften up" over time.

1. Just try an adjustment yourself. All you have to do is remove a front wheel and adjust it with simple handle tools.

2. It's not normal.

3. Even the same brand can have manufacturing defects across different batches/lots.

[weehe126]

Originally Posted by Polo08816

It's pretty simple... you just take the wheel off and they are right there. You just the make the adjustment with simple hand tools...

You have to do the adjustment with the wheels on and on the ground. So you would need to put the front on ramps.

[Polo08816]

Originally Posted by weehe126

You have to do the adjustment with the wheels on and on the ground. So you would need to put the front on ramps.

Wouldn't that cause more weight to be shifted to the rear and affect the settings?

My impression would be that unless someone has a 4 post drive on lift, adjustments would be estimates or approximations.

I will say that most high end coilover setups like Ohlins and AST as well as the M Performance Suspension kit are set at about 10mm lower than the RWD 704 Sport Suspension ride height. You would be able to use the factory endlinks.

[GuestBen]

Originally Posted by johnung

Not yet. I’m juggling several projects right now. I also want to drive on them some more to see if they soften up. My current thoughts are:

1) Maybe they just need adjustment? I have great faith in the guys who installed them and they’ve offered to adjust. But I want to investigate other ideas first.

2) Could just be normal? But I haven’t heard from other guys who’ve installed adjustable end links to know if that’s the case.

3) Perhaps it is just this brand? I bought the KC Design’s because FaRKle! recommended them and did an installation video featuring them. He also said that unlike others on the market, the KCD’s had dust covers to prevent dirt from getting into the joint and ruining it. No others had dust covers, although Hotchkis now appears to have dust covers too, but at a much higher price.

ANYONE WHO HAS INSTALLED ADJUSTABLE END LINKS OF ANY BRAND, PLEASE CHIME IN. THANKS!

Hey John - I believe you and I have mostly similar setups...2015 335i XDrive, Koni Special Active shocks/struts with F80 bump stops, Eibach springs, H&R sway bars, VAC front upper/lower control arms, strut tower brace...and adjustable end links, except mine are from SPL. I'm also running Millway street camber plates. I've had the adjustable end links installed for nearly two years and I can't say I've noticed anything like you're describing when going over road imperfections. Maybe it's a break in/settling thing?

PS, I finally got the OEM F22 15mm rear bar (33556853476) you and others have recommended...looking forward to getting the swap done.

Good luck with the troubleshooting!

[casualDIYer]

Originally Posted by johnung

ANYONE WHO HAS INSTALLED ADJUSTABLE END LINKS OF ANY BRAND, PLEASE CHIME IN. THANKS!

I have the exact same end links you have. The KC Design. So far, good quality endlinks with no issues. These are the steps I took based on Farkle's video.

For the front

1. Attach the endlink to the strut endlink mount. Despite being a pain in the a$$, taking the wheel off to do this is going to be a lot faster than trying to attach the endlink to the strut with the wheel on. Once attached, wheel on.

2. As weehe126 mentioned, drive the car up a set of ramps that you can still fit under, get under the car, and before adjusting the endlink length and attaching it to the ARB, study the ARB in more detail. Your goal is to check the ARB bushings do not have any play in them. Sure that the bushings are fine, let the ARB drop to it's natural resting state i.e. a state in which there will be no preload, adjust the length of the endlink, and attach it to the ARB. The bolt of the endlink is likely to be perpendicular with the mounting hole of the ARB. This is important.

You should also try to move the adjuster to be in the centre of the selected length. In other words, an equal amount of thread should protrude from each end of the endlink to the ball joint by an equal amount.

As for the rear, on my car, I found I had to set the endlinks to their minimum size to ensure no preload.

If adjusting the endlink has become hellishly difficult because the wheel is in the way, there's no space for tools, and you have little leverage because you are lying on your back . . . you must be doing it right. I hope.

Good luck.

[Eschmacher]

I wish I could tell you if my adjustable endlinks made any noise, but the noise from my struts/camber plates drowns out any other noise that is present. I am honestly not sure what to do about it at this point. Probably ditch the Bilstein damptronic struts entirely. Not sure if it's the struts or the camber plates that are bad. Off topic, but does anyone know how to get a hold of anyone at millway? I have used their contact form twice and haven't seen any response.

Current setup is eibach prokit, bilstein b6 damptronic, H&R front sway bar, millway street camber plates, and some adjustable endlinks that HPA sold me that were absolutely not the correct length for this car and I had to cut down to fit. Absolutely do not buy the endlinks HPA sells for the F2X/F3X.

[mike082802]

I have bimmerworld adjustable endlinks (front only)with ohlins road and track coilovers and they are silent. Millway camber plates, f80 front arms and poly subframe bushings, 275/35/18 square tires

[Polo08816]

Originally Posted by mike082802

I have bimmerworld adjustable endlinks (front only)with ohlins road and track coilovers and they are silent. Millway camber plates, f80 front arms and poly subframe bushings, 275/35/18 square tires

How did you get those to fit? Are your Ohlins R&T coilover spring perches adjusted at their maximum preload setting?

[casualDIYer]

Originally Posted by Eschmacher

I wish I could tell you if my adjustable endlinks made any noise, but the noise from my struts/camber plates drowns out any other noise that is present. I am honestly not sure what to do about it at this point. Probably ditch the Bilstein damptronic struts entirely. Not sure if it's the struts or the camber plates that are bad. Off topic, but does anyone know how to get a hold of anyone at millway? I have used their contact form twice and haven't seen any response.

Current setup is eibach prokit, bilstein b6 damptronic, H&R front sway bar, millway street camber plates, and some adjustable endlinks that HPA sold me that were absolutely not the correct length for this car and I had to cut down to fit. Absolutely do not buy the endlinks HPA sells for the F2X/F3X.

How wide are your tires? I found this makes a difference with respect to noise.

As for the Millway camber plates, I was able to add a ring of sound ablating material between the top of the spring (with the strut rubber boot protector, that keeps dust and dirt away from the damping rod, on) and the plate. It made a small difference. As for the plates themselves, check the urethane ring to see if has worn and do not/not over torque the adjustable camber plate.

[Eschmacher]

Originally Posted by casualDIYer

How wide are your tires? I found this makes a difference with respect to noise.

As for the Millway camber plates, I was able to add a ring of sound ablating material between the top of the spring (with the strut rubber boot protector, that keeps dust and dirt away from the damping rod, on) and the plate. It made a small difference. As for the plates themselves, check the urethane ring to see if has worn and do not/not over torque the adjustable camber plate.

235/45/18, only one size above stock.
I assume you mean between pieces 5 and 1 here? https://www.realoem.com/bmw/enUS/sho...diagId=31_0950

And good callout on the torque, I may redo that since I didn't install them.

[casualDIYer]

Originally Posted by Eschmacher

235/45/18, only one size above stock.
I assume you mean between pieces 5 and 1 here? https://www.realoem.com/bmw/enUS/sho...diagId=31_0950

And good callout on the torque, I may redo that since I didn't install them.

As surprising as it might sound, wider tires do soak up bumps a lot better. I was skeptical but I run 225 square in the winter and 255 square in the summer. It's almost night and day in terms of comfort, with the wider tire running more comfortably. If you have a friend with an F30 and wider tires, go for a test drive.

On the diagram, between the strut bearing and the plate as in the following photo

[johnung]

Originally Posted by casualDIYer

How wide are your tires? I found this makes a difference with respect to noise.

As for the Millway camber plates, I was able to add a ring of sound ablating material between the top of the spring (with the strut rubber boot protector, that keeps dust and dirt away from the damping rod, on) and the plate. It made a small difference. As for the plates themselves, check the urethane ring to see if has worn and do not/not over torque the adjustable camber plate.

My entire setup and all components were chosen for Street Performance with maximum comfort since it’s our daily driver that we tak on trips.

I am running square 255/40-18 Michelin Pilot Sport 4S that are only two months old. Yes, wider width soaks up bumps better. So does 18” sidewalls vs shorter sidewalls on 19”/20”. The MPS4S themselves are know for soaking up bumps/potholes. The difference was a dramatic improvement when I went from runflats to MPS4S.

I got a good baseline driving the new tires for weeks before the stock end links were swapped out for the KC Design end links. Then the thumping began. So I know that the issue has something to do with them: their adjustment, their construction, their design, a defective set, etc. Several possibilities that will have to be sorted.

So far I’ve heard from some guys who have the same end links as well as other brands. All report positive experiences with neutral ride and no thumping.