Dry rubbing/grinding noise (rotational)

[Gib]

Has this issue for a while now (4 months) - ever since I got some poly bushes fitted to my front and rear wishbones. I have had the car into two garages - One is an Audi Specialist the other is a guy who has a good rep for working on VW/Audi cars.

The noise is coming from the front end and you can hear it more when driving slower, like pulling up to junctions. At first i thought it was the brakes catching but have been checked and its not that.

First garage had a look and couldn't find anything even though they could hear the noise. I took a trip to Center Parcs one weekend and with driving slow around site the nose sounded terrible. I had a quick look and noticed a load of grease on the inner cv joint (Bingo!!) I thought this was the fault. Changed it.... still doing it!

The second garage had the car over a week, he went though everything he could think of -

-Track rods
-Ball joints
-Drive shafts
-Brakes
-ARB
-All the bolts attaching subframe
-Wheels
-Struts

All he found was a loose heat shield which was touching the drive shaft very slightly. Reshaped it and was still there.
Now upon picking the car up I drove it for a few days and the noise was hardly there - the guy said he's had it up on the lift most of the time, which makes me think it relax's something and when driving on the road it settles back in.

The guy was very kind and didn't charge the earth for his time and said that nothing is going to drop off and everything seems to be where it should be.... it could be more internal? like your quattro system or diff.

Ive been having a search on here and I believe the propshaft bearings can be changed? the noise is more excessive when more people are in the car too.

Sorry for the long write up just trying to find out what this noise can be!
Cheers Rich

 

[S3-LINCS]

mine had a bolt loose in the front prop bush that sounded like this it backed out just enuf to catch the tranny box,

was a pain to find I thought it was the brakes at first

 

[Gib]

Ill have a look at this, many thanks! Is the bolt easy to get too?

 

[S3-LINCS]

PITA there is 3 either side of the bush mine was at the front so I could see it while I rolled the car backwards with my head under the bonnet lol.
I think there 10mm multipline bolts,

 

[dave_beastttt]

mine had a bolt loose in the front prop bush that sounded like this it backed out just enuf to catch the tranny box,

was a pain to find I thought it was the brakes at first

I've had this too, twice, the bolt works it's way loose and rubs on the housing of the transfer box, a very light metallic rotational grinding sound can be heard when pulling up at lights. Don't leave it though as it turns into a massive noise.

To tighten up you need to wedge some things against the donut cover and transfer box so you can fit a 10mm ring spanner on the bolt to tighten it.

I would suggest using some Loctite 221 on the thread.

 

[Gib]

Many thanks! I'll have a look at this tomorro and see, it is a PITA noise!

 

[S3-LINCS]

that's it mate.

made an awfull noise and a right mess of my old transfer box

 

[Gib]

At first I put it down to the poly bushes, as it started just after, but also at the same time I lowered the car from 10mm to 35mm, so thought that may have changed how a few things sit in position

 

[Gib]

Haven't had time to get the car on lift, but managed to get under the car to have a look at propshaft - the bolts as in the pic are nothing like that..... But I did find this

Seems oil/grease as come out of the joint and leaked.
Cars going in for a service end of the month and going to change gear box oil too just to make sure the transfer box is ok

 

[S3-LINCS]

wrong bolts mate, you want to be looking under the bonnet at the back of the engine you should be able to see the 3 front bolts around your doughnut bush