Very Unusual road noise A3 2009 1.9tdi

[A3car19tdi]

I have this humming and or roaring noise coming from we think the rear of the car. It will change quite dramatically depending on road surfaces ,quiet on smooth and roaring on a poor road but always there.

The tyres are reasonably new. I have just taken it to my local garage mate. Both him and one of his mechanics took it on a drive and can both hear it but neither can pin it down. They have had it on the ramp and checked the bearings and the tyres and are stumped.

Anyone have any thoughts ?  

 

[Magnet]

Hello Dan,

Worth trying swopping back tyres to front - and vice versa? 
Kind regards,

Gareth. 
 

[A3car19tdi]

On 1/12/2022 at 6:32 PM, Magnet said:

Hello Dan,

Worth trying swopping back tyres to front - and vice versa? 
Kind regards,

Gareth. 
 

Well, I have now tried swapping the rear wheels to the front and the noise is still there exactly the same.  It's a similar sound to if you blow across the top of a glass bottle quietly. Sort of.

There is a particular stretch of road near me that changes from a rough surface to a new smooth surface . The change in sound is remarkable when I hit the smooth surface.  It virtually dissapears.

Most odd. Seems to be coming from the back somewhere.

 

Anyone have any thoughts ?

[JMKC82]

Hi,

Is it definitely not the road?  Road with drainage cuts are so loud.

Anyway, instead of swapping tyres front to back, rotate the tyres.  Not sure if your car is quattro (i don't think so) or directional tyres?

https://www.google.co.uk/search?q=rotating+tyres&source=lnms&tbm=isch&sa=X&ved=2ahUKEwiA6Obg1_f1AhVIQMAKHdKkC3YQ_AUoAnoECAgQBA&biw=1536&bih=722&dpr=1.25

On my old VW golf, i used to get loud road noise.  Garage thought it was the bearings but found nothing when on the ramps.  Rotated the tyres, and after 2000 miles the noise was drastically reduced.  Some cars / tyres develop a "saw tooth" which can be really bad.

https://www.continental-tires.com.gh/car/technology/tyre-knowledge/lex-1-3-1

[A3car19tdi]

43 minutes ago, JMKC82 said:

Hi,

Is it definitely not the road?  Road with drainage cuts are so loud.

Anyway, instead of swapping tyres front to back, rotate the tyres.  Not sure if your car is quattro (i don't think so) or directional tyres?

https://www.google.co.uk/search?q=rotating+tyres&source=lnms&tbm=isch&sa=X&ved=2ahUKEwiA6Obg1_f1AhVIQMAKHdKkC3YQ_AUoAnoECAgQBA&biw=1536&bih=722&dpr=1.25

On my old VW golf, i used to get loud road noise.  Garage thought it was the bearings but found nothing when on the ramps.  Rotated the tyres, and after 2000 miles the noise was drastically reduced.  Some cars / tyres develop a "saw tooth" which can be really bad.

https://www.continental-tires.com.gh/car/technology/tyre-knowledge/lex-1-3-1

No, it's not a quattro.  

So do you mean swap the wheels  side to side on the car?

 

It's dreadful. I have to get to the bottom of it now. I thought bearings but garage guys  Def said not the bearings but couldn't tell what it was.

Rather not go to the expense of new tyres as they are not too old just to eliminate it. 

 

[JMKC82]

rotating tyres / wheels is not always as simple as side to side.  Depends if your tyres are directional.  Check if all your tyres are the same brand, and take a high res picture of the entire tyre side wall and stick it here.  I'll take a look.

[cliffcoggin]

Did the noise start when you fitted the new tyres? If so, it's the tyres making the noise and there is nothing you can do about it. The noise from tyres varies a lot from brand to brand, just as the wet grip, the endurance, and the price also vary.

[A3car19tdi]

Here is the tyre image.  

 

The tyres were already on the car when I had it.

Edited February 11, 2022 by A3car19tdi
Extra picture

[JMKC82]

those tyres look fine.  But if you wanted to rotate them, do this.  I assume they are uni-directional.

[A3car19tdi]

Yes they are normal.   Nothing states they are directional. 

I could try rotating them.    It's just strange. I can detect the sound at slow speeds even 10 mph but it's quite a change crossing onto a very smooth surface at 20/30/40mph.  It almost virtually dissapears then.

Cross Back on to a rough tarmac and it starts howling away.

 

 

[Stevey Y]

2 hours ago, A3car19tdi said:

Yes they are normal.   Nothing states they are directional. 

I could try rotating them.    It's just strange. I can detect the sound at slow speeds even 10 mph but it's quite a change crossing onto a very smooth surface at 20/30/40mph.  It almost virtually dissapears then.

Cross Back on to a rough tarmac and it starts howling away.

 

 

Hi Budget tyre won't help, Prestivo is not one I have ever heard of, example being as a cab I use a lot of rubber in a good year so went to my local tyre supplier for new fronts, as he didn't have my usual Nexen tyres in my size he asked me to trial these new tyres he was thinking of selling called Stomil, ok I said, as soon as I reached the first roundabout all hell broke loose and it sounded like both front bearings had collapsed so I took it back and gave him a test drive, he wasn't impressed so he fitted the only other tyres he had in that size Semprit which were dearer but wouldn't take the difference in the price, these were about as quite as you can get with a 68db noise rating and peace was restored, there are so many mid range good tyres out there, Next ,Debica, Roadstone, Mid range is as low as I go.

Steve.