Slight humming sound at low speeds (faint)

[GGill]

Hi all,

I have a 2016 640d GC with 31k on the clock. I recently changed all my Dunlop RT maxx tyres to Michelin PS4s (non RTs), mainly to enjoy the ride more. I currently have 373m 20" alloys so they are low profile.

When I changed the front tyres (fronts done first), and 4 wheel alignment I started to notice a low frequency hum at 30-38mph. It soon disappears (or become very faint) over 38mph. It's also isn't not noticeable at very low speeds i.e below 30mph.

The hum comes and goes i.e. it's not constant like it's catching? Funny enough on perfect tarmac its not noticeable. Weird!

I must admin I didn't notice when when I had the Dunlop's RT maxx, but I definitely had some alignment issue especially under braking which is now resolved.

Its now more obvious since the alignment was addressed. Perhaps it masked other issue?

Note I've had the car checked twice by bmw (after warranty check) in July and again in August and all was good.

So...

1/ Could it be a wheel bearing (see it mentioned a lot) even though this was checked for twice 3 months ago and it's pretty low mileage?!
2/ The tyres as it's not the recommended by BMW?
3/ Humming made more obvious once alignment was addressed (it does run much smoother now). So something with alignment?
4/ Not correctly inflated tyres? (Perhaps RT tyres are different. 38 front and 41 rear psi)

Any ideas would help!

BTW The humming or hum is very faint so simply putting the radio and you forget. It's noticed however by a slight vibration in the steering wheel at certain points. Again not constant.

GG

[thebmw]

Always tough to diagnose based on a post. However, I had a similar issue recently and it was a wheel bearing issue. Does the humming increase when you're turning in one direction or the other?

[GGill]

Originally Posted by thebmw

Always tough to diagnose based on a post. However, I had a similar issue recently and it was a wheel bearing issue. Does the humming increase when you're turning in one direction or the other?

Originally Posted by thebmw

Always tough to diagnose based on a post. However, I had a similar issue recently and it was a wheel bearing issue. Does the humming increase when you're turning in one direction or the other?

So I tried turning at the sweet point and no difference in the sound.

Now that I'm more aware of it it's now pretty much humming (again very faint) at 15mph to around 32mph. Costing seems to make it more apparent perhaps as there is not engine noise?

I might get Bmw to check it then decide...

[thebmw]

Usually with wheel bearings, it's always there to some extent. Sometimes road noise drowns it out. It also seems more apparent when turning, thus loading the bearings more or less.

[doggboy]

Is it possible you have some a-hole friends?

[GGill]

Originally Posted by doggboy

Is it possible you have some a-hole friends?


Attachment 2183112

[QUOTE=doggboy;25480058]Is it possible you have some a-hole friends?

Haha!!! Nice one Doggboy!

[GGill]

Update

BMW finally got their hands on the car and have confirmed its the bearings! Interestingly early in the day of the original post above (18th Nov) I hit a pothole hole and BMW have confirmed it was the cause!

I managed to raise a calm with local council's claims team and look forward to sending all invoice details and evidence to them for a reimbursement.

BMW have been good enough to state this on their invoice!

[GGill]

Originally Posted by GGill

Update

BMW finally got their hands on the car and have confirmed its the bearings! Interestingly early in the day of the original post above (18th Nov) I hit a pothole hole and BMW have confirmed it was the cause!

I managed to raise a calm with local council's claims team and look forward to sending all invoice details and evidence to them for a reimbursement.

BMW have been good enough to state this on their invoice!

Also do they need to be done in pairs?

[GGill]

Originally Posted by GGill

Also do they need to be done in pairs?

Unbelievable! They supposedly fixed the issue and I've paid only to find out on my way back that it's still making the noise!

I can't believe this! Did they forget to do what they've promised?

I immediately went back to the dealer and said it's not fixed and now need to book it in again!

[thebmw]

From what you told me, it did not sound like a wheel bearing issue. So maybe that's why the problem is still there.

[GGill]

Originally Posted by thebmw

From what you told me, it did not sound like a wheel bearing issue. So maybe that's why the problem is still there.

I suspect it's the Michelin PS4's cause it starting happening pretty much after I replaced the RT Dunlop's!!? Annoying it was the same time I hit the pothole!

Also when it hit near perfect tarmac it's quite which points to the tyres!

I think BMW have jumped on the opportunity to slap me with a huge bill to replace the bearings!

See what happens tomorrow! If they don't play ball I'll ask to have my old bearing replaced and go elsewhere!

[Opie55]

I don't think you said how many miles are on the car. But a 2016 probably should not need a wheel bearing. But for future reference, just by the way you phrase things I think you put too much confidence in dealers. They don't know everything and sometimes they are kinda dumb. Anytime you are diagnosing a mystery noise they may just be guessing. I had a high pitch vibration/noise in an MB that went away when I turned off the AC. Thankfully under warranty, they replaced nearly every component of the AC system. Turned out to be a power steering hose.

[GGill]

Originally Posted by Opie55

I don't think you said how many miles are on the car. But a 2016 probably should not need a wheel bearing. But for future reference, just by the way you phrase things I think you put too much confidence in dealers. They don't know everything and sometimes they are kinda dumb. Anytime you are diagnosing a mystery noise they may just be guessing. I had a high pitch vibration/noise in an MB that went away when I turned off the AC. Thankfully under warranty, they replaced nearly every component of the AC system. Turned out to be a power steering hose.

I've only covered 31,000 miles

[thebmw]

Originally Posted by Opie55

I don't think you said how many miles are on the car. But a 2016 probably should not need a wheel bearing.

My 2015 needed the wheel bearings replaced. They said it was because of a pothole. The difference is, the fix worked on my car.

[GGill]

Originally Posted by thebmw

My 2015 needed the wheel bearings replaced. They said it was because of a pothole. The difference is, the fix worked on my car.

So at the end new bearing were installed (managed to see them after removing centre hub caps). They also showed me the old bearings which indeed made some noise.

So to conclude this thread...

1/ Passengers side wasn't healthy due to the pothole. BMW have added this information to invoice for the council to review. Can't see the council getting out of this one. (But lets see)
2/ Driver side was also changed. I know they don't need to be done in pairs but it also making a slight noise. BMW dealer is however awaiting a possible goodwill gesture for the driver side to be approved by the onsite warranty manager due to the current low mileage.
3/ If point 2 fails to happen I have informed the dealer that I will raise this with BMW UK. The old bearings (driver side esp) will be kept for further investigation. They've surprisingly agreed that it shouldn't happen on a low mileage car and that the supplier is at fault. Also this isn't the first time they said.
4/ Technician test drove the car with me and also drove the car and confirmed the noise is tyre noise from the Michelin PS4's. We also drove over some slick tarmac and noticed the difference. The workshop manager also spent some time explaining that the PS4's do make more noise generally due to the thread design.

I'm still a little unsure as to the 'noise', just feels the same. Perhaps the bearing issue was masked by the softer compound of the non RT Michelins plus I had the wheels aligned at the same time. (BMW checked all wheels and the rears are fine thankfully as it's far more expensive to replace). I do very much remember the ride was horrid on the RTs Dunlop's.

I'm now armed the the necessary info. If things go wrong I'm straight onto the dealers case! I'll accept the current situation and take some piece of mind that all is good now specially when travelling with family.

If BMW come good then that's half the saving. If the council also agree damages then it's a win win!

The Dunlop's RT = hasher ride but less
road noise??

Michelin PS4s = softer ride but more road noise??

[JBF650]

Originally Posted by GGill

So at the end new bearing were installed (managed to see them after removing centre hub caps). They also showed me the old bearings which indeed made some noise.

So to conclude this thread...

1/ Passengers side wasn't healthy due to the pothole. BMW have added this information to invoice for the council to review. Can't see the council getting out of this one. (But lets see)
2/ Driver side was also changed. I know they don't need to be done in pairs but it also making a slight noise. BMW dealer is however awaiting a possible goodwill gesture for the driver side to be approved by the onsite warranty manager due to the current low mileage.
3/ If point 2 fails to happen I have informed the dealer that I will raise this with BMW UK. The old bearings (driver side esp) will be kept for further investigation. They've surprisingly agreed that it shouldn't happen on a low mileage car and that the supplier is at fault. Also this isn't the first time they said.
4/ Technician test drove the car with me and also drove the car and confirmed the noise is tyre noise from the Michelin PS4's. We also drove over some slick tarmac and noticed the difference. The workshop manager also spent some time explaining that the PS4's do make more noise generally due to the thread design.

I'm still a little unsure as to the 'noise', just feels the same. Perhaps the bearing issue was masked by the softer compound of the non RT Michelins plus I had the wheels aligned at the same time. (BMW checked all wheels and the rears are fine thankfully as it's far more expensive to replace). I do very much remember the ride was horrid on the RTs Dunlop's.

I'm now armed the the necessary info. If things go wrong I'm straight onto the dealers case! I'll accept the current situation and take some piece of mind that all is good now specially when travelling with family.

If BMW come good then that's half the saving. If the council also agree damages then it's a win win!

The Dunlop's RT = hasher ride but less
road noise

Michelin PS4s = softer ride but more road noise.

GGill, mate, not to confound you here and if this all turns out well for you then good one!
however I do find this very odd and most perplexing re greater noise levels with the Michelins Vs the Dunlop RFT. when I changed to the Michelins Pilot 4s I noticed how immediately quiet the ride was, how much more improved the grip was and how much better the car rides compared to those horrible RFT.
I've not noticed any humming or noise at all coming from my Michelins. My car too is a very low Klm car , currently 30K klms.
anyway as I said I hope this is solved for you now but in my experience it was the dreadful RFT's that were noisy, harsh and had a slight vibration on my 650. the best thing I ever did was piss the RFT off.

cheers

JBF

[GGill]

Originally Posted by JBF650

GGill, mate, not to confound you here and if this all turns out well for you then good one!
however I do find this very odd and most perplexing re greater noise levels with the Michelins Vs the Dunlop RFT. when I changed to the Michelins Pilot 4s I noticed how immediately quiet the ride was, how much more improved the grip was and how much better the car rides compared to those horrible RFT.
I've not noticed any humming or noise at all coming from my Michelins. My car too is a very low Klm car , currently 30K klms.
anyway as I said I hope this is solved for you now but in my experience it was the dreadful RFT's that were noisy, harsh and had a slight vibration on my 650. the best thing I ever did was piss the RFT off.

cheers

JBF

Hey JBF!

Perhaps I might get the tyres rebalanced later when I get the alloys refurbed to be sure. I guess mechanical the car is 'sound' for now! Pardon the pun!

Perhaps I've become desensitised / forgotten what the RFT were really like! I completely agree that ride was horrible and everything was x10 when you hit a bump in the road! Perhaps the sniff feel perverted certain road noise? I don't know...

I'll probably swap the fronts around to see if that makes a difference or even ask someone to be kind enough to lend me their 6 series to compare?

Going back to when I first had the PS4s I did notice a vast difference. But with all the drama immediately after I've probably become "too" aware of the road noise in general lol?

Anyway I'll pick away slowly to determine a happy medium as am sad like that or until the wife's had enough 🙂