Low speed drone/hum speed related

[Gf Jon]

Hi
Can anyone suggest any other possible areas to check...
I have an a4 b6 avant 3.0 six speed Quattro. I hear a drone from front most noticeable when slowing from 30 to a stop its driving me crazy ! Like something winding down. Sure I can feel it slightly thru pedals etc.
Work done so far ; brand new 18" wheels and tyres all round, new front wheel bearings(main dealer) new front discs and pads, new front driveshafts genuine, main dealer also checked all front suspension as have I. Brake calipers stripped, cleaned, greased sliders, checked caliper mounts etc all ok.
I've started looking at back brakes and intend to check prop bearing but I'm fed of trying to track this noise out.
Any one got a similar noise ?
It's cost a small fortune so far ... Any help deeply appreciated.
Jon

[Mikelb01]

My PCV valve made a humming sound at low speeds or when idling. Might be worth checking out?

[blitz2190]

Have the exact same issues with the same fixes so far, I'm thinking it might be a bent wheel or bad axel but as you replaced the wheels I'm now leaning toward an axel.

[Gf Jon]

I replaced axles from car with only 17,000 miles on the clock. Made no difference. I'm thinking maybe my Poss wheel or wheels as they are after market ones with directional tread tyres. However changing them round or even running them backwards made no difference to the noise or tone. I'm going to have them checked tomorrow at a tyre shop so will let you know. Althought I'm almost positive the noise was there before I changed the wheels.
It seems to be more noticable when the weight shifts forwards .... Im still on the case will keep you posted.

[Gf Jon]

I had all wheeks checked and rebalanced yesterday, no problems found and tech said there's no wear yet in tyres to cause noise.
However I did discover that the front drivers side lower control arm rear inner bush has lots of play and I can actually twist the arm quite a bit with pry bar. I checked other side and no such movement...... Could this be my problem?
Also gearbox mount seems to have a lot of play if I lift it with pry ba r ? Help !!

[diagnosticator]

Check for sloppy/ rough/ noisy wheel bearings.

[SlickFix]

Have you also confirmed that the dust shields are not bent and scraping lightly against the rotors? I had that happen to me once after I replaced the pads.

[Gf Jon]

Hi
Wheel bearings were replaced at main dealer plus I double checked when I changed the driveshaft.
Checked the back plates to and are spot on but it's not aback plate sort of noise .... When I was in it yesterday it sounds like a swarm of bees almost and I'm sure I can feel a corresponding feel of it thru pedals etc
It IS definitely wheel/speed related. In other words it's def a rotational noise

[Gf Jon]

My pcv valve is fine and I have checked all vac pipes but it is def connected to road speed as engine makes no noise when stationary or revved

[diagnosticator]

That leaves only the tires for the droning noise.

[Gf Jon]

Not tyres .... Why would only one do it when all brand new plus I have rotated them and noise stays in same place :-/

[jpulll]

Check out your suspension. What comes to mind when you say low speed drone/hum speed related, a wheel bearing pops in my mind. Any hum going on when you take turns a certain way or is it only when coming to a stop? Suspension is tough to diagnose unless you are there driving the car and just have had experience with shit going wrong.

[Gf Jon]

Lol believe that !
The lower control arm rear inner bush is worn. I removed it at outer ball joint and it has about 6" easy back and forth play which can't be right. So maybe that's the Prob and its next on the list to do .....
Maybe it's allowing the wheel to move a lot more than it should?
Could it be some Prob with the caliper not sitting right/warped or possibly brake pads even tho they are new.
Feel like my audi is taking over my life !

[Gf Jon]

Right just incase you are suffering similar Prob... I have had all wheels checked for trueness, all four balanced, garage confirmed no wear on tyres. Having them rebalanced sorted high speed wobble but droning noise still persists!?!?
However I just replaced my inlet manifold and variable intake system and all vac pipes. Plus cleaned injectors while out. My car now goes like a bat out of hell !!! I can't believe the difference it made..... So there's some GOOD NEWS lol

[jpulll]

Right just incase you are suffering similar Prob... I have had all wheels checked for trueness, all four balanced, garage confirmed no wear on tyres. Having them rebalanced sorted high speed wobble but droning noise still persists!?!?
However I just replaced my inlet manifold and variable intake system and all vac pipes. Plus cleaned injectors while out. My car now goes like a bat out of hell !!! I can't believe the difference it made..... So there's some GOOD NEWS lol

I like the sound of that, i need to do injector o rings/seats as well as my pcv system. can't wait to see the difference.

[Gf Jon]

Update on droning noise ....
After renewing the dodgy front lower control arm .... No difference lol. However the noise has got worse and now the time of the noise definitely changes on a fast left hand bend and is sounding more and more like a wheel bearing ! I'm beginning to believe it wasn't replaced at the main dealers at all !!!
Order a new one so will let you know ...

[Darjan]

any update on this?

[sgudino]

I have been out of town for about a 5 months and when I returned i noticed it was time for a tire rotation when I made the change I noticed that a rough sound was coming from the front of the car, I then later reviewed the sound and it appears to be coming from the rear of the vehicle. It turned out to be the rear wheel bearings based on my ears and 2 technicians. I am ordering the *** brand which includes the hub. I will keep everyone posted on this discovery.

[slow_N_lowe]

I am ordering the *** brand which includes the hub. I will keep everyone posted on this discovery.

Please post the brand and part number if you're able to source the bearing and hub as an assembly.

[Gf Jon]

Hi been a while. Update on droning vibration .. Changed both front wheel bearings myself and guess what the main dealer never touched the bearings!!! They both had quite a lot of sideways slack. Noise reduced by 75% ... Further investigation leads me to believe front os disc calliper area is causing the remaining noise that was underlying the bearing noise all the time .... Keep you posted
Jon