E89 Z4 35i adaptive M suspension squeaks

[raweden]

I have a 35i with the adaptive suspension option. With the roof down driving around town at slow speeds I have noticed that the suspension permanently squeaks when set in Normal mode. If I stiffen the suspension to sport mode the squeak improves and then disappears completely in sport+ setting. The car has been back to my dealer who replaced the front suspsension struts under warranty, but this didn't fix the squeak, it's exactly the same. The car has also been tested with the anti roll bars detached and this makes no difference ie squeak remains.
Anyone else with the adaptive suspension option noticed this squeak? - you need to be in a built up area with roof down and ideally windows down (walls reflect the squeak back into the car so you hear it only in built up areas). We only really use the car for driving holidays so it is used with the roof down most times so this is quite annoying!

[zEdP]

Originally Posted by raweden

Anyone else with the adaptive suspension option noticed this squeak? -

No problem here. I guess a bad shock absorber or cover.

EdP

[T89]

This is odd. No problems for me. Maybe it's something else that's squeaking..?


T

[Memphis1]

nope... that is odd, but let us know what the dealership says. I can only imagine the shocks, bushings or housings to squeak and even then I've only heard really old cars squeak.

[juhap]

No squeaks here either, but my E85 did develop an annoying squeak when a small stone got lodged somewhere in the suspension.

[Vintage]

no problems like that for us and I am very sensitive to squeaks

[raweden]

Thanks guys will let you know what BMW say. As I mentioned the front suspension struts were changed for new units and the technician says it can't be bushes as it would make the squeak all the time, however it must be suspension related as setting the suspension to Sport + gets rid of it (and hardens ride so if it was something else you would expect it to get worse). I would like to drive another Z4 with the adaptive suspension just to compare. Problem at moment in UK is there are hardly any around so will have to wait and see. Thanks again.

[raweden]

To update I have had my 35i back at the dealers and the senior technician has listened to the squeaks. He is convinced they are coming from the front suspension struts as the sound comes with compression and releaase of the dampers.

The dealer has a severe rubber speed ramp and when the car is driven over it (roof down, windows down) you can hear two little squeaks one when the front wheels hit the hump, the other a fraction of a second later when it comes down the other side. There is no sound when the rear wheels go over the hump. The technician also says he has heard this exact type of sound on bike forks and believes it's the air moving quickly in/out of the forks. He also says that one of the older 5 series used to do this.

In other words its a characteristic of the adaptive suspension. I do tend to agree with him bearing in mind I have had 2 new front dampers on the car (which has only 4000 miles on it) and there's nothing else I can conceivable think of, and neither can BMW. Proof will be for me to drive another Z4 with adaptive suspsension and this will be the next step when (if?) my local dealer ever gets one in with this option.

To hear the bird like squeaks (which are in stereo!) you have to be in a quite, built up area with narrow streets and high walls/buildings close to the road to reflect sound, a reasonably bumpy road, roof & windows down, driving less than 30 mph with the suspensuion set to 'normal'.

[Silver-Bolt]

Could be the springs moving on the rubber isolaters. When you stiffen the shocks the springs compress less and have less movement. Try spraying some lube on the top and bottom of the springs. Ideally between the spring and the rubber.

[tot]

Originally Posted by raweden

To hear the bird like squeaks (which are in stereo!) you have to be in a quite, built up area with narrow streets and high walls/buildings close to the road to reflect sound, a reasonably bumpy road, roof & windows down, driving less than 30 mph with the suspension set to 'normal'.

My car does the same thing, the sound coming only from front. I haven't noticed difference between normal and sport mode, but then again I haven't paid too much attention.

[BlueZ4AZ]

Originally Posted by raweden

To update I have had my 35i back at the dealers and the senior technician has listened to the squeaks. He is convinced they are coming from the front suspension struts as the sound comes with compression and releaase of the dampers.


In other words its a characteristic of the adaptive suspension. I do tend to agree with him bearing in mind I have had 2 new front dampers on the car (which has only 4000 miles on it) and there's nothing else I can conceivable think of, and neither can BMW. Proof will be for me to drive another Z4 with adaptive suspsension and this will be the next step when (if?) my local dealer ever gets one in with this option.

When ever a technician says someting like, "...its a characteristic of the adaptive suspension." what they really mean is, "We've tried as hard as were going to and we're not going to help you any further on this issue"

One response to their comment would be, "not everyone has the squeeks, so it's not a normal characteristic, so please continue to do whatever is necessary so my suspension does not squeek any more. Here are my keys, call me when the squeeks are gone"

[Silver-Bolt]

Originally Posted by BlueZ4AZ

When ever a tehnician says someting like, "...its a characteristic of the adaptive suspension." what they really mean is, "We've tried as hard as were going to and we're not going to help you any further on this issue"

One response to their comment would be, "not everyone has the squeeks, so it's not a normal characteristic, so please continue to do whatever is necessary so my suspension does not squeek any more. Here are my keys, call me when the squeeks are gone"

Blue,
That is so true. Our Cooper-S was bought back as a lemon and we had to fight for that to happen. In our state the lemon states if a vehicle is in 3 times for the same problem and not fixed it qualifies for lemon status. We found out our paperwork was worded differently each time so it appeared not to be the same issue. Short story was they bought it back. Keep firm with them. Squeeks are not normal. The comment about motorcycle forks is bogus as well. The forks are sealed and do not expell air. Document everything and be sure the documentation is correct.

[Dr Stig 2]

Originally Posted by raweden

I would like to drive another Z4 with the adaptive suspension just to compare.

Sounds like a great excuse to drive a 35is and give us a comparison review!
Take Clarkson along for the drive to get his opinon as well.

[Mr. ///M3 RD]

Originally Posted by Dr Stig 2

Sounds like a great excuse to drive a 35is and give us a comparison review!
Take Clarkson along for the drive to get his opinon as well.

If he can afford his hourly rate, and then he would give him the unless it is a 2009 3.5i

[Dr Stig 2]

Originally Posted by Rolf-Dieter

If he can afford his hourly rate, and then he would give him the unless it is a 2009 3.5i

I would love to know what spec car Clarkson drove.
Did it have the DCT and active suspension? Over here BMW imports come specced with almost everything unless you order one especially yourself.

(They make more money that way - "Ahh yes, I know it says $110K on the brochure, but with paint, wheels, leather, air in the tyres and the dirt taken off the windshield, that comes to $3.8M..."

[teagueAMX]

Originally Posted by raweden

The technician also says he has heard this exact type of sound on bike forks and believes it's the air moving quickly in/out. . .

In other words its a characteristic of the adaptive suspension.

To hear the bird like squeaks

As others have aptly stated he's wrong, and I hope he's just stupid and not lying. I can add that based on 1st hand experience of hearing automotive shocks compress/decompress at a very close distance that is not the sound they make. It is a dull swish-hissing sound. More like a outdoor water hose valve opening - with the hose on the valve so all you hear is a quite hiss as the water fills the hose. Additionally, it is not an intense sound nor is it high pitched like a bird chirp or squeak. You have to be very close to hear the sound - something not possible from inside your car, especially while driving and the motor running.

The basic operation of a "DCT Damper" is really quite similar to a normal damper. The DCT mechanizm is a electro-mechanically controlled orifice that fluid goes through. As others have stated, it move less in Sport/Sport+ mode by restricting the amount damping fluid flowing through it.

My 1st choice would be torsion bar bushings, but you ruled that out. I then would look at the spring seats, and a 3rd high probability is the aluminum substructure frame that supports the suspension. Rubber, or more likely, synthetic material, bushings or damping materials can be responsible for that type of sound. A loose bolt may do it as well.

[raweden]

Thanks teague, will talk further to BMW and let you know outcome. Have just come back form 2 weeks drivng 2500 miles around Spain, Italy, France mostly with the top down. The squeeks were annoying me more and more as I'm now tuned into them and just can't believe this is normal.

[raweden]

An update - I managed to track down another 35i with adaptive M suspension at another dealers in the UK. After discussing with BMW they arranged for me to go and drive it to see if it made the same chirps/squeaks as my 35i. I drove it yesterday and guess what, it does make exactly the same squeaks. The service manager who accompanied me in the car I test drove also clearly heard the noises and seemed a bit surprised.

I have reported it back to my dealers who will report it back to BMW, not that I think anything can be done about it, more for BMWs information - maybe they will make an adaptation in the future. But it does seem that this is a characteristic of the adaptive M suspension. I believe this is the first small car that BMW have fitted this suspension to and my local BMW technician had already told me that he had heard this type of suspension noise coming from an older 5 series.

I suspsect many owners with cars with the adaptive suspension on it will not have noticed the squeaks as you do need to be on rough roads (ie like the UK!) in a built up area with walls/other parked cars/buildings close by (a few feet) to reflect the sound made by the suspension back into the car. You need to have the roof down or both windows fully open and driving at less than 30 mph. Having driven a lot in the US I suspect its much rarer to come across the sort of narrow, bumpy road conditions needed to hear the suspension.

Ah well I'll just have to flick to sport + when I drive through the centres of quite villages if I want to get rid of the squeaks, but don't know if my back and neck can stand it.....

[Geodoc]

Originally Posted by raweden

I suspsect many owners with cars with the adaptive suspension on it will not have noticed the squeaks as you do need to be on rough roads (ie like the UK!) in a built up area with walls/other parked cars/buildings close by (a few feet) to reflect the sound made by the suspension back into the car. You need to have the roof down or both windows fully open and driving at less than 30 mph. Having driven a lot in the US I suspect its much rarer to come across the sort of narrow, bumpy road conditions needed to hear the suspension.

.....

I have the squeak - doesn't bother me though - roads in Ireland would be bad in places and like you I only hear it in built up places.

[mrboon]

I get it as well now, it seems to be getting worse and worse over time.

I have been to BMW yet, but will tell them during the next service.

[Land_Shark]

Question: the adaptive M suspensions are mostly designed for the tuned Z 35is. Could this problem that raweden is having demonstrates that, only on the 35i?? I have noticed another 2 members on this thread to confirm the squeak, but from their profiles, they too drive a 35i and not a 35is...
Does anyone who have the 35is hear this squeak??

[Soki...]

Originally Posted by Land_Shark

Question: the adaptive M suspensions are mostly designed for the tuned Z 35is. Could this problem that raweden is having demonstrates that, only on the 35i?? I have noticed another 2 members on this thread to confirm the squeak, but from their profiles, they too drive a 35i and not a 35is...
Does anyone who have the 35is hear this squeak??

I think the adaptive M suspension is an optional that anyone can have and not depending if you have the 23i, 30i, 35i or the 35is. So, I suppose that anyone that has the adaptive M suspension on his car may have this problem.