Resonating whirrr noise from rear

[Venom]

As the title says, my 330ci (E46) had a noise which makes itself known at 85-110Km/h. I get a small vibration at that speed, but no major vibrations or anything else.

Here is what I have done:

Wheel Balancing
Rear Wheel Bearings
Just changed the diff oil. (the diff oil was dark gold, new oild was light gold...I am not a beleiver of lifelong oils.)
Alignment is done
New tyres (Changed after I heard the noise, so it is not the tyres)

What my next plan of action is:
Have the propshaft checked (Bearings etc) and also the diff Bush.

I will ley you guys know what we find..if anything.

Suggestions are most welcome. The noise is from the rear of the car. It is not loud, but I can hear it and I know that it is not normal.

Anyone had this problem before?

 

[Bayn46]

Can you hear it coming from any particular side at the rear or is it somewhere in the middle?

Control arms might need checking.

 

[akash]

Just have a look at your wheel arch covers

 

[Venom]

Can you hear it coming from any particular side at the rear or is it somewhere in the middle?

Control arms might need checking.

Hi Bayn46,

Pretty much the middle. Wishbones, and all rear control arm bushes were replaced about 8 months ago.

Regards

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Just have a look at your wheel arch covers

akash,

That is a bloody good suggestion. Your thinking would be if it is loose, it could be vibrating at speed I assume. I will check that.

Thanks

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Can you hear it coming from any particular side at the rear or is it somewhere in the middle?

Control arms might need checking.

Hi Bayn46,

Pretty much the middle. Wishbones, and all rear control arm bushes were replaced about 8 months ago.

Regards

---

Just have a look at your wheel arch covers

akash,

That is a bloody good suggestion. Your thinking would be if it is loose, it could be vibrating at speed I assume. I will check that.

Thanks

---

So the rear covers are solid, no movement, BUT, one front one has a fastening nut missing and is loose. I'll fasten it, but I am dea certain that the noise is from the rear.

 

[roboman]

Any work done on the brakes lately. Could be loose caliper.

 

[Venom]

Any work done on the brakes lately. Could be loose caliper.

Hi Roboman, it's won't be the caliper as the noise was there before we changed the bearings and then after. (We obviously removed and refitted the braking system)

We now know that it is not the prop shaft and it noww seems like the diff is also fine.

On further investigation, between myself, the propshaft place and Bruce's mechanical, we now beleive it could well be the rear left rim that may be slightly out of shape. When we ran the car on the hoist the rear left wheel looked a bit odd. It seemed to run a touch unevenly. It was very marginal, but I could see it.

I am now going to change the rim and I beleive that the noise will be gone. Will let everyone know.

 

[herr bmw]

was going to sugest the rim is buckeled,but noticed you changed tyres,so they would have picked it up.

had the same on my car and found the rims ont he passenger side buckled,front worse.got repaired and noise and vibration gone

 

[Venom]

was going to sugest the rim is buckeled,but noticed you changed tyres,so they would have picked it up.

had the same on my car and found the rims ont he passenger side buckled,front worse.got repaired and noise and vibration gone

Thanks Herr BMW, got any idea where I can take it in Cape Town to be checked and repaired. And how long did it take them to fix it? BTW - They fitted the tyres and never noticed anything. I am identifying it as the rim as we have eliminated almost everything else. Rule of thumb...start with the inexpensive items first :facepalm:

My car is extremely well maintained and part of the problem is that I hear voices, I mean things in my car that no one else hears. Part of the issue is that no-one else hears what I am talking about. But, the sound id there for sure.

 

[herr bmw]

sorry stay in pretoria,but they took two days too sort it out.they loaned me two shocking red rims with tyres to drive around with.

some people loved the red ,i hated it

 

[Venom]

sorry stay in pretoria,but they took two days too sort it out.they loaned me two shocking red rims with tyres to drive around with.

some people loved the red ,i hated it

Bet you would have been enev more popular if those rims were blue.:rollsmile:

 

[frikkieh]

Now this seems like a very familiar sound.
Check out my thread here

The next step would have been to replace one of the rear rims - It has been for a mag repair once. It is balanced perfectly, we did the chalk test and no issues there. But this would be my last avenue apart from replacing the Diff output bearings, just because.

I replaced the rear brakes (disks and pads) and the rear wheel bearings. It is still the same.

"I mean things in my car that no one else hears" I have the exact same problem here.

I concluded that it can be the road surface that I use daily to work and back or to try the a fore mentioned (rims output bearing)