[ruczko]

Hey all, had my car lowered by a local tuner shop here in Vancouver. Since having it lowered I've been getting a more prominent knocking sound coming from the driver side. Sounds like a spring binding issue? Its most often during parking lot speeds that you hear it.

Shop is trying to point towards control arms although its unlikely as you hear it most during slow turns of the wheel. I had a BMW tech look at it and he's suggesting its the spring too. Even the tuner shop thinks its the springs not having enough pre-load? Either way, I need to get it sorted.

Another forum member with a 330xi (M Sport) H&R Springs also had this issue, installed at the same shop ironically.

I'm stuck because I don't know if its an issue with the spring, the install or something different.... Anyone else having this issue? Is it possible this is an H&R Spring fault?

My options as I see them... install factory springs back (not ideal), order a different set of springs altogether (Dinan or something) or possibly get another pair of H&R springs to try...

Looking for some suggestions.

[Fpangalos]

Originally Posted by ruczko

Hey all, had my car lowered by a local tuner shop here in Vancouver. Since having it lowered I've been getting a more prominent knocking sound coming from the driver side. Sounds like a spring binding issue? Its most often during parking lot speeds that you hear it.

Shop is trying to point towards control arms although its unlikely as you hear it most during slow turns of the wheel. I had a BMW tech look at it and he's suggesting its the spring too. Even the tuner shop thinks its the springs not having enough pre-load? Either way, I need to get it sorted.

Another forum member with a 330xi (M Sport) H&R Springs also had this issue, installed at the same shop ironically.

I'm stuck because I don't know if its an issue with the spring, the install or something different.... Anyone else having this issue? Is it possible this is an H&R Spring fault?

My options as I see them... install factory springs back (not ideal), order a different set of springs altogether (Dinan or something) or possibly get another pair of H&R springs to try...

Looking for some suggestions.

Can you post a video link of the noise you are hearing.... the fact that you are hearing the noise only at low speed turns make me think it's the upper mounts of your struts. Very common for installers to dent the upper bearings in mounts during installation. Once the bearing is dented, you will hear it catch when taking turns at low speeds. At higher speeds it glides faster and is less noticeable.

Sucks to hear! Goodluck!

[TheDudeMan]

Sounds like an installer issue. I just installed my springs, diy, and have no issues.

As the previous poster mentioned, it sounds like either the strut mount bearings or a loose suspension component. I would double-check the sway bar endlinks. They are easy to forget to tighten.

The other thing I would do is tighten up the top strut main bolt in the middle and double-check all the surrounding bolts. There's really no much to the front suspension of these cars.

[ruczko]

Originally Posted by TheDudeMan

Sounds like an installer issue. I just installed my springs, diy, and have no issues.

As the previous poster mentioned, it sounds like either the strut mount bearings or a loose suspension component. I would double-check the sway bar endlinks. They are easy to forget to tighten.

The other thing I would do is tighten up the top strut main bolt in the middle and double-check all the surrounding bolts. There's really no much to the front suspension of these cars.

Is this bolt accessible without taking the suspension out?

[thakid22]

Originally Posted by ruczko

Hey all, had my car lowered by a local tuner shop here in Vancouver. Since having it lowered I've been getting a more prominent knocking sound coming from the driver side. Sounds like a spring binding issue? Its most often during parking lot speeds that you hear it.

Shop is trying to point towards control arms although its unlikely as you hear it most during slow turns of the wheel. I had a BMW tech look at it and he's suggesting its the spring too. Even the tuner shop thinks its the springs not having enough pre-load? Either way, I need to get it sorted.

Another forum member with a 330xi (M Sport) H&R Springs also had this issue, installed at the same shop ironically.

I'm stuck because I don't know if its an issue with the spring, the install or something different.... Anyone else having this issue? Is it possible this is an H&R Spring fault?

My options as I see them... install factory springs back (not ideal), order a different set of springs altogether (Dinan or something) or possibly get another pair of H&R springs to try...

Looking for some suggestions.

Take a look at the springs.... At normal ride height, do you see two or more coils that are touching (or very close to touching)? If so, they can make noise (a springy popping sound) when you turn the steering wheel at parking lot speeds or travel over not smooth pavement slowly.

The answer is to install coil spring isolators, so that the touching coils no longer touch. They are cheap and easy to install. You won't have to take anything apart. Just jack the car up and slip them on the spring.

You'll likely know exactly where to put them, because you will see the paint rubbed off of the spring in the spot between the coils that are making noise, when you have the car jacked up.

And as someone else mentioned, make sure the top strut shift nut is tight.

[TheDudeMan]

Originally Posted by ruczko

Is this bolt accessible without taking the suspension out?

Yes. It's under your hood, at the top of the strut.

[ruczko]

Originally Posted by TheDudeMan

Yes. It's under your hood, at the top of the strut.

Ok, found it. Stupid question. How do I tighten it? Using the bolt or an Allen key?

[TheDudeMan]

Originally Posted by ruczko

Ok, found it. Stupid question. How do I tighten it? Using the bolt or an Allen key?

Tighten the bolt. But you'll need to hold the allen in place. Take it back to the shop and have them check it.

[ruczko]

Originally Posted by TheDudeMan

Tighten the bolt. But you'll need to hold the allen in place. Take it back to the shop and have them check it.

any idea what this should be torqued to?

[TheDudeMan]

Originally Posted by ruczko

any idea what this should be torqued to?

Not positive. I would make sure it's tight, and at min 100ftlbs.

Also, it's odd that the sound is only coming from the driver's side. If it were the springs binding, it would happen on both sides. Furthermore, the reason I suspect it's the install is that the driver side is not any different when compared to the passenger side outside of an extra cable for the break wear sensor.

[franky818]

Did op fix this ? I have the same knocking noise on H&r on my g20 haha ... crazy

[A172]

same here

install was perfect so just gonna lube up everything whenever i get some time

would report back

[ruczko]

Took it in today and they noticed the rubber covering the tip of the spring (no idea what it's called) had moved down. Sounds like they moved it back up and it seems to be quiet for the moment. Let's hope that's all it was.

[A172]

Originally Posted by A172

same here

install was perfect so just gonna lube up everything whenever i get some time

would report back

ok so got around to this and it was easy to see the spring coils were touching each other

moved the coil rubbers a little higher and lubed up everything, all is well now

[TheDudeMan]

Originally Posted by A172

ok so got around to this and it was easy to see the spring coils were touching each other

moved the coil rubbers a little higher and lubed up everything, all is well now

The springs are progressive and the coils are tighter at the top. Just slide the isolators higher. You'll probably need to jack the car up and take the wheel off.

[ruczko]

Originally Posted by TheDudeMan

The springs are progressive and the coils are tighter at the top. Just slide the isolators higher. You'll probably need to jack the car up and take the wheel off.

So far that looks like that was the issue.... the shop did just that and the noise has gone away. Fingers crossed it stays that way.

[TheDudeMan]

Originally Posted by ruczko

So far that looks like that was the issue.... the shop did just that and the noise has gone away. Fingers crossed it stays that way.

I'm sure it will, it makes sense.

[SJA05]

Originally Posted by TheDudeMan

The springs are progressive and the coils are tighter at the top. Just slide the isolators higher. You'll probably need to jack the car up and take the wheel off.

What isolators are you referring to? I've tried searching isolators/insulators and they are referring to the the rubber that the spring inserts into at the top (and bottom?) of the springs themselves - sort of like a spring perch. Is what you are referring to something different - like rubber inserts that go between the coils of the springs? If so, where do you source them from?

My H&R springs do make a sort of crunching sound whenever I go over bumps slowly. I've had the top bolt re-torqued to 100+ ft/lbs.

Thanks

[TheDudeMan]

Originally Posted by SJA05

What isolators are you referring to? I've tried searching isolators/insulators and they are referring to the the rubber that the spring inserts into at the top (and bottom?) of the springs themselves - sort of like a spring perch. Is what you are referring to something different - like rubber inserts that go between the coils of the springs? If so, where do you source them from?

My H&R springs do make a sort of crunching sound whenever I go over bumps slowly. I've had the top bolt re-torqued to 100+ ft/lbs.

Thanks

Some springs are equipped with rubber covers that wrap around the coils at the progressive end of the spring since it's tightly wound and clearances are tighter. I have Dinan springs, but they are not progressive and do not have this as a design element. Furthermore, if the springs don't load up when installing the top mount back onto the strut, you can experience clunking when the spring unloads.

In addition, anyone know what the H&R instructions state to do with the bump stops? From experience, lowering springs usually come with shorter bump stops or require you to cut them.

Unfortunately, suspension clunks are very annoying as they are difficult to diagnose and can be caused by infinite factors.

[SJA05]

Thanks for the explanation, much appreciated!

I got the H&R springs because Dinan still hasn't released springs for the M340iX, and I wasn't willing to wait for a 3rd summer (I got mine in 2019) with my car jacked up like an SUV.

What I did do is order the Dinan bump stops (I forget the fancy name they use for them), and replaced the stock bump stops with the Dinan's (even though they are technically for the RWD M340i). I have the adaptive suspension and the ride has been excellent even on the firmest setting, and the handling improvements have been very noticeable (less pitch and dive, flatter cornering, and crisper turn-in).

I can definitely live with the trade-off of a little noise when going over bumps at parking lot speeds for the much improved handling and looks.