[lolekbolek]

Hi everyone, I apologize if this has been discussed before but I couldn't find it.

I own a F31N 2017 which started to develop a clunk when the outside temperature is more than 25°C/77°F and the car is warmed up from driving it.

It makes the noise when I start from a standstill, brake and just drive normally.

The clunk is coming form the front passenger wheel area and if I kick the tire I can make it to make the noise.

Here is the link to a video of how it is after driving in the city when it was 37°C/99°F outside.
https://drive.google.com/file/d/1SR2...ew?usp=sharing

I took it to the dealer to try and get this sorted but they describe this as a car in "perfect" condition, which I highly doubt.

So after that I took it to a local guy where we unscrewed the sway bar and link but it still made when starting and braking. Then we replaced the thrust arm but it still didn't cure the clunk. Right now I'm waiting for hot weather so I can warm up the car and then lift it to try and find the origin but if someone has suggestions they would be greatly appreciated.


Thanks in advance.

[Eschmacher]

Damn, thrust arm was going to be my first guess.

Find a better shop, if you can reproduce it that easily, any right-minded mechanic would never tell you it's in "perfect" condition.

My thoughts are basically anything else on the suspension... strut mount, the strut itself, lower control arm, maybe the hub/bearing.

Edit: this is a RWD model, correct?

[lolekbolek]

Originally Posted by Eschmacher

Damn, thrust arm was going to be my first guess.

Find a better shop, if you can reproduce it that easily, any right-minded mechanic would never tell you it's in "perfect" condition.

My thoughts are basically anything else on the suspension... strut mount, the strut itself, lower control arm, maybe the hub/bearing.

Edit: this is a RWD model, correct?

The funniest thing is that teh official BMW service show wrote me a work order where it says that the car is in perfect condition.

I tried to move the lower control arm whrn the car was on the lift but it didn't have abnormal play in it.

The bearing was inspected by the same shop but they wrote it's fine but how much you can believe them is a good question. I have an appointmen at another dealer who is apparently more competent in 2 weeks time to change the brake pads and to take a look at this but I'm still gonna do some research on my own since I do quite a bit of driving and the clunk is driving me insane.

And yep it's a RWD.

[lolekbolek]

A little update. Yesterday I got my wheels balanced and while the car was warm and happily making the sound I hate, I asked the guys if I can take a look and I think both of the thrust arm bushings are too soft and the bushing was cracked a bit.

The first time we changed the thrust arm we only replaced the passenger one and not driver side one so that could be the reason the clunk was not cured the first time we tried to diagnose it.

Here are the links to the videos (warning to headphone users, the sounds are terrible in the background):
https://drive.google.com/file/d/1cVC...ew?usp=sharing
https://drive.google.com/file/d/1uGU...ew?usp=sharing

If someone has more experience I'd love a comment or some advice, Thanks!

[casualDIYer]

I too am suffering a dreaded clunk and after spending time silencing the 6 tons of plastic underneath my car, and replacing perfectly good sway bar end links, I said "Hold on, hold on . . . it's probably the dreaded steering rack clunk."

Got the kit. Got the grease. Waiting for the magic tool to get that cap off.

Google "F30/F31 steering clunk". To confirm,

1. Park car on level ground
2. Shut off car completely, like you would when parking
3. Rapidly turn steering wheel left and right 10-15%. Hear the clunk?

The EPS steering rack uses a plastic piston to push the pinion and rack together. The piston wears over time since it's made of a material of less resiliency than the replacement part. The fix-it kit is reasonably priced ~USD$30. The grease too is also inexpensive ~USD$9

Except for every single car made with the old piston, no other car would have the problem. Why don't others complain? Two words. LEASE CAR

[Polo08816]

Originally Posted by casualDIYer

I too am suffering a dreaded clunk and after spending time silencing the 6 tons of plastic underneath my car, and replacing perfectly good sway bar end links, I said "Hold on, hold on . . . it's probably the dreaded steering rack clunk."

Got the kit. Got the grease. Waiting for the magic tool to get that cap off.

Google "F30/F31 steering clunk". To confirm,

1. Park car on level ground
2. Shut off car completely, like you would when parking
3. Rapidly turn steering wheel left and right 10-15%. Hear the clunk?

The EPS steering rack uses a plastic piston to push the pinion and rack together. The piston wears over time since it's made of a material of less resiliency than the replacement part. The fix-it kit is reasonably priced ~USD$30. The grease too is also inexpensive ~USD$9

Except for every single car made with the old piston, no other car would have the problem. Why don't others complain? Two words. LEASE CAR

So I believe this thrust bearing kit and tool is only applicable to Variable Sport Steering racks made by Thyssen Krupp. The notes for this repair kit in RealOEM also indicate that it's for a specific steering rack manufacturer.

The ZF steering rack thrust bearing can be opened with a standard hex socket. But when you open it and look at the thrust bearing piece, it's actually different than the one used in the Variable Sport Steering rack. I wasn't able to use a needle nose plier to remove it because there's nothing for the plier to grip to in order to pull it out from the rack. The color is also similar to the thrust bearing in the repair kit as opposed to the color of the original VSS rack's thrust bear (white/yellowish).

[casualDIYer]

Seems like ZF might have picked the better of the two materials. As for the steering rack itself, it is the Thyssen rack that develops the problem. The fix is a Thyssen fix as well. More importantly, did your steering rack clunk when turning the wheel left and right 10 degrees when the car is off? That is the test for a worn thrust bushing. If the car made no noise, I’d conclude the thrust bushing is not the problem. If you did get the clunk during the test and there is no repair kit for the ZF, that would suck. Does it mean the ZF rack needs replacement? I hope not

[Polo08816]

Originally Posted by casualDIYer

Seems like ZF might have picked the better of the two materials. As for the steering rack itself, it is the Thyssen rack that develops the problem. The fix is a Thyssen fix as well. More importantly, did your steering rack clunk when turning the wheel left and right 10 degrees when the car is off? That is the test for a worn thrust bushing. If the car made no noise, I’d conclude the thrust bushing is not the problem. If you did get the clunk during the test and there is no repair kit for the ZF, that would suck. Does it mean the ZF rack needs replacement? I hope not

I don't notice a clunk when the car is off when turning the wheel left to right. I am waiting for the replacement steering tie rods and I'm going to replace that. The inner tie rod end is the only suspension component that is original to the car at 140,000 miles.

[casualDIYer]

Originally Posted by casualDIYer

I too am suffering a dreaded clunk and after spending time silencing the 6 tons of plastic underneath my car, and replacing perfectly good sway bar end links, I said "Hold on, hold on . . . it's probably the dreaded steering rack clunk."

Got the kit. Got the grease. Waiting for the magic tool to get that cap off.

Google "F30/F31 steering clunk". To confirm,

1. Park car on level ground
2. Shut off car completely, like you would when parking
3. Rapidly turn steering wheel left and right 10-15%. Hear the clunk?

The EPS steering rack uses a plastic piston to push the pinion and rack together. The piston wears over time since it's made of a material of less resiliency than the replacement part. The fix-it kit is reasonably priced ~USD$30. The grease too is also inexpensive ~USD$9

Except for every single car made with the old piston, no other car would have the problem. Why don't others complain? Two words. LEASE CAR

Did the steering fix and now the steering is definitely tighter (the steering wheel does return to centre so it's not too tight) but the clunking is still there.

Just like previous 3 series, it seems like the current car is destined to become a cursed rattlebox. I guess podcasts and SiriusXM are going to have to keep my mind off it.

[Polo08816]

Originally Posted by casualDIYer

Did the steering fix and now the steering is definitely tighter (the steering wheel does return to centre so it's not too tight) but the clunking is still there.

Just like previous 3 series, it seems like the current car is destined to become a cursed rattleboxes. I guess podcasts and SiriusXM are going to have to keep my mind off it.

That is frustrating. Are the tie rods original in the car?

[casualDIYer]

Originally Posted by Polo08816

That is frustrating. Are the tie rods original in the car?

They are original. Might be time for a swap. But I do have some positive news. I swapped out the front thrust arm bushing for millway’s street monoballs today and the thunk is much diminished. It doesn’t seem like the origin of the thunk is gone but the older bushings were making the problem worse. It may indeed be the struts but at 80,000km it seems early for them to begin to die….

[Polo08816]

Originally Posted by casualDIYer

They are original. Might be time for a swap. But I do have some positive news. I swapped out the front thrust arm bushing for millway’s street monoballs today and the thunk is much diminished. It doesn’t seem like the origin of the thunk is gone but the older bushings were making the problem worse. It may indeed be the struts but at 80,000km it seems early for them to begin to die….

So I think I know what the grinding/crunching/binding noise in my front suspension is due to. I was working on the steering tie rods today and I noticed that when I grab the passenger side brake caliper and brake disc and turn the front wheels, I feel slight binding/grinding when I apply opposite force to the passenger side's brake caliper and rotor in an effort to turn the front suspension. The sound seems like it emanates from the wheel hub assembly. When I do the same to the brake caliper and rotor on the driver's side, I don't get that noise. You would think if it's related to the turning of the front wheels/hubs, you would hear the noise no matter where you turn the front suspension to some extent. But if the noise is actually coming from a failing wheel bearing, then you wouldn't if there is no load on the bearing. So this noise is hard to replicate when the car is on jackstands and the front wheels are not in contact with the ground. At least that's my theory, but I replaced the front wheel bearings 50-70k miles ago with the SKF ones on FCP Euro. Now it is possible that when you track a car, the wheel bearings fail sooner due to heat, but I didn't think that soon.

[sjreid]

^ Could well be the wheel bearings again, especially if used on the track.

Always hard to diagnose by just spinning the wheel and feeling for play.

[lolekbolek]

Hi, just to update,

After waiting for ages to get a spot by a reputable dealer they inspected it and found that both thrust arm bushings were the main cause so they replaced them on each side and some other small bushings. Since the car has extended warranty I only had to pay 10% of the price for parts. I've ben driving clunk free for a week now and I couldn't be happier.

The only thing that I noticed is that the car feels a bit unstable on the highway, like when it's windy outside and it's pushing the car left and right. And with the steering it feels like there is a small dead zone in the middle. So I'm gonna guess they didn't do the best alignment and I'm gonna take it to a specialist that only deals with wheels and alignments and I'll update if that fixed it.

Thank you to everyone that was replying

[Polo08816]

Originally Posted by Polo08816

So I think I know what the grinding/crunching/binding noise in my front suspension is due to. I was working on the steering tie rods today and I noticed that when I grab the passenger side brake caliper and brake disc and turn the front wheels, I feel slight binding/grinding when I apply opposite force to the passenger side's brake caliper and rotor in an effort to turn the front suspension. The sound seems like it emanates from the wheel hub assembly. When I do the same to the brake caliper and rotor on the driver's side, I don't get that noise. You would think if it's related to the turning of the front wheels/hubs, you would hear the noise no matter where you turn the front suspension to some extent. But if the noise is actually coming from a failing wheel bearing, then you wouldn't if there is no load on the bearing. So this noise is hard to replicate when the car is on jackstands and the front wheels are not in contact with the ground. At least that's my theory, but I replaced the front wheel bearings 50-70k miles ago with the SKF ones on FCP Euro. Now it is possible that when you track a car, the wheel bearings fail sooner due to heat, but I didn't think that soon.

Originally Posted by sjreid

^ Could well be the wheel bearings again, especially if used on the track.

Always hard to diagnose by just spinning the wheel and feeling for play.

I replaced the passenger side wheel bearing and 90-95% of the clunking is gone now.

[casualDIYer]

Finally fixed the front end clunk. What a relief. It was the left side front strut. Swapped out with after market struts. Much improved handling and clunk is gone.

[Polo08816]

Originally Posted by casualDIYer

Finally fix the front end clunk. What a relief. It was the left side front strut. Swapped out with after market struts. Much improved handling and clunk is gone.

My issue turned out to be the control arms I bought from RockAuto under the Delphi brand. Go with original unless Lemforder or Meyle HD are options.

[casualDIYer]

Originally Posted by Polo08816

My issue turned out to be the control arms I bought from RockAuto under the Delphi brand. Go with original unless Lemforder or Meyle HD are options.

I'm doing those next. During alignment this year, they are so seized it took forever to get them adjusted.

Question: Have you being hearing of issues with non-BMW branded OEM parts prematurely failing? I've had a couple of mechanics tell me some of the of their most reliable OE suppliers have been sending parts that have failed prematurely.

[Polo08816]

Originally Posted by casualDIYer

I'm doing those next. During alignment this year, they are so seized it took forever to get them adjusted.

Question: Have you being hearing of issues with non-BMW branded OEM parts prematurely failing? I've had a couple of mechanics tell me some of the of their most reliable OE suppliers have been sending parts that have failed prematurely.

Absolutely. My Delphi M3 control arm's ball joints did not have nearly the same tolerances as genuine control arms. They were far too loose and failed within 5,000 miles on installation. Meanwhile, my genuine control arms on the other side have over 40,000 miles on them.

I ended up ordering through FCP Euro because I know there's a good chance I'll have to replace these control arms again later on down the road when they wear out after 50+k miles.

[amico_polacco]

Originally Posted by lolekbolek

Hi everyone, I apologize if this has been discussed before but I couldn't find it.

I own a F31N 2017 which started to develop a clunk when the outside temperature is more than 25°C/77°F and the car is warmed up from driving it.

It makes the noise when I start from a standstill, brake and just drive normally.

The clunk is coming form the front passenger wheel area and if I kick the tire I can make it to make the noise.

Here is the link to a video of how it is after driving in the city when it was 37°C/99°F outside.
https://drive.google.com/file/d/1SR2...ew?usp=sharing

I took it to the dealer to try and get this sorted but they describe this as a car in "perfect" condition, which I highly doubt.

So after that I took it to a local guy where we unscrewed the sway bar and link but it still made when starting and braking. Then we replaced the thrust arm but it still didn't cure the clunk. Right now I'm waiting for hot weather so I can warm up the car and then lift it to try and find the origin but if someone has suggestions they would be greatly appreciated.


Thanks in advance.

Hi, I'm facing the same issue as you've described for the past year and a half. My car has since been to the BMW dealerships and different specialists and no one has figured out the source of the clunking noise. Could you please make your shared videos available again so I could confirm it?
Thanks!

[lolekbolek]

Originally Posted by amico_polacco

Hi, I'm facing the same issue as you've described for the past year and a half. My car has since been to the BMW dealerships and different specialists and no one has figured out the source of the clunking noise. Could you please make your shared videos available again so I could confirm it?
Thanks!

Hi, In the end I managed to fix it by a BMW dealer to which I got through some connections. All the bushings on the control arms on the left and the right side had to be replaced. The end bill with labour came to 190€ but the car was still in warranty at that time, so I only had to pay for 10% of the parts cost which was I think 13€ or something like that.

The links expired but I generated new ones for you. Hope it helps.
https://drive.google.com/drive/folde...ui?usp=sharing

[Polo08816]

Originally Posted by lolekbolek

Hi, In the end I managed to fix it by a BMW dealer to which I got through some connections. All the bushings on the control arms on the left and the right side had to be replaced. The end bill with labour came to 190€ but the car was still in warranty at that time, so I only had to pay for 10% of the parts cost which was I think 13€ or something like that.

The links expired but I generated new ones for you. Hope it helps.
https://drive.google.com/drive/folde...ui?usp=sharing

Ah, yes, the control arms.