[Gee195]

G31, standard suspension, 17" non runflats.

On worn concrete roads (90% here in Belgium) the suspension makes , besides the normal suspension noise, a very low frequency resonance sound, as a low bass frequency.

It's most noticable on low speeds, below 60 km/h, getting worse coming to a stop. On smooth asphalt, there is no resonance.

It is driving me mad, never experienced this with any ( and a lot cheaper) other car. Even my 13 year old Ford Focus was limousine comfort compared to this car. Overall comfort of the suspension and sound level of this car is very disappointing, not at a level you would expect from a 5-series.

We test drove a g30 berline, no resonance; another g31 with 19" run flats : more tire roar but no resonance ...

Several wheels tested, front bearings changed, no difference.

A engineer from BMW Belgium did a long testdrive, to come to the conclusion this is normal noise, due to the excessive use of aluminum and weight savings Is it maybe common BMW policy, just denying the issue?

Any similar experiences?

[HighlandPete]

Originally Posted by Gee195

G31, standard suspension, 17" non runflats.

….

We test drove a g30 berline, no resonance; another g31 with 19" run flats : more tire roar but no resonance ...

Several wheels tested, front bearings changed, no difference.

A engineer from BMW Belgium did a long testdrive, to come to the conclusion this is normal noise, due to the excessive use of aluminum and weight savings Is it maybe common BMW policy, just denying the issue?

Any similar experiences?

No experience... are you sure it is suspension related? As the other cars didn't resonate and wheel changes made no difference, I'd be looking to things like heat shields, engine acoustic cover, undertrays, etc., as the first things to check.

As to BMW 'policy' and denying an issue, not sure others are having issues with these near silent cars. The other two examples you have tried not having a problem is a clue there is something unusual going on.

[Gee195]

I will pass your suggestions to my dealer. I don' t know if there is an issue with the suspension, but it seems to me the suspension movement is creating the vibration and resonance. It' s frustrating BMW Belgium is not more pro active ...

[Zap-xpilot]

Originally Posted by HighlandPete

No experience... are you sure it is suspension related? As the other cars didn't resonate and wheel changes made no difference, I'd be looking to things like heat shields, engine acoustic cover, undertrays, etc., as the first things to check.

Tyres.

Check a similar car, with a different tyre make and also with a different width.
I remember thinking I had a differential issue this summer while steaming on autobahn, just to drive there two months later, with a different car, but same brand of tyres (Michelin) albeit different products (Cup 2 vs Primacy 3RFT) and experiencing the same sound. My friend on one of the occasions, riding on Pirellis, thought I was hearing noises in my head.

[Gee195]

Unfortunately it's not the tyres, nor the rims.

We tested several different wheelsets with different tyres : 17", 19", rft, non rft, summer, winter ... No difference.

We tested the same wheelsets on another 520d sedan: no resonance sound.

[GRLNE]

I realise this is an old thread but I have the same issue on a 2021 540i Touring (19" non-runflats), so I'm very interested in the outcome.

Did you get a resolution to this loud, uncomfortable and intrusive resonance noise?

Thanks.

[ctour]

Also having this issue. All rough parts of the road creates a really annoying low frequenzy noise that is really annoying.

BMW 520D 2019. Has not had any accidents that could cause this..

I'm really disappointed. My 2016 F11 did not have this issue.

Any idea of how to fix this?

[GRLNE]

I didn't get the high speed noise solved, or the general resonance in the cabin over bumps - turns out G31s are just noisy cars. I had an E61 previously from new for 13 years and it was silent on almost all surfaces, brilliantly quiet in the cabin. But after receiving my new G31 and finding it so noisy in comparison I eventually got to drive two other similar cars to compare with and found that all the G31s are very loud in comparison to E and F series - both wind noise through the driver door seals and road noise through the tyres.

However, the low frequency droning at around 25-27mph on anything but a mirror smooth surface has been solved.

It was vaguely audible on the other two cars I tried, but nowehere near as bad as mine.

BMW fitted Pirelli noise cancelling tyres (P Zero PNCS) to the front, and that got rid of it. They're not OEM approved tyres (well they are for Mercedes and Jaguar, but not BMW), and they weren't available in PNCS for the rear tyre size (because Mercedes and Jaguar don't use that size), but changing the front ones did get rid of that intrusive and very annoying humming.

I hope you find a solution, it's a maddening problem to have on such an expensive car.

[CnSky]

A new set of BMW alloys I purchased new with tyres came with front accoustic tyres from factory.

They must know there is an issue.

The tyres are like those on a Tesla they have a foam ring inside.

Mine are star marked MPS3s.

[my5401]

I have a G30 2020 540i xDrive. I get the resonance when I'm on certain SMOOTH looking roadways. I have factory supplied tires with one of them being replaced by the dealership after a blowout. BTW the resonance was there before the tire replacement.

The worst offender is a stretch of smooth asphalt on M-14 outside of Ann Arbor. I looked to see if there was some very "low frequency" waviness to the road and didn't notice any.

[bjan_84]

Gee195 Was this issue ever solved?