Strange noise from the rear at low speed when turning

[86fran]

I've had my S3 8L since February and it hasn't missed a beat (flew through its mot a couple of weeks ago too )

Today I noticed a strange noise when I was in a car park turning.

Basically there is a vibrating/rubbing (almost like the handbrake has been left on) sound coming form the rear of the car when turning.
The noise doesn't appear to be there when going in a straight line or at speed.
I have jacked both sides up at the rear and wiggled the wheel/checked for any play and they seem ok (i.e. no wheel bearing issue).
Nothing appears to be hanging off back there!
The springs look in good condition, as do the CV boots.
The wheels rotate freely with the handbrake off and lock with it on as they should.

Does anybody have any ideas what it could be?

 

[Vex182]

Could be the haldex dragging, is the 4wd system working?

 

[86fran]

I'm not sure, how do I check that it is or not?

I tried turning off the ESP as I read something about the haldex, but it doesn't change the noise at all?

 

[Vex182]

Best way I found was ESP off, find somewhere where your rear wheels are on grass and give it a sharp pull away, when I peer out my door I can see the rears wheel spin. Others can probably give another way to test it.

 

[86fran]

I've read about removing the haldex fuse to see if the noise stops at all?

The car has been well looked after and the haldex was serviced not long before I bought the car earlier this year.

I also read about possible CV issues? I thought these 'clicked' rather than vibrate/grind/rubbing type noise though so starting to think the worst...

 

[nick's]

The mrs had a similar problem with her old 1.8T A3, it turned out to be the rear caliper sliders sticking, Audi sorted it under warranty

I remember going out on a rd test with an Audi tech, at slow speed he pulled the handbrake & it stopped

Worth a try, you never no

 

[The Doctor]

Is it only noticeable at very low speeds (ie 5mph)? It may be that above this you can't hear it due to road/wind noise.

Some questions
- can you hear it on the outside of the car (ie wind the window down and listen carefully)?
- is it the same on left and right turns?
- nothing at all in a straight line at the same speed?

From what you describe, it sounds like it's more diff-related than Haldex-related to me. If it only does it when turning and is the same in either direction then that points to the diff operation. I'd try draining the oil out of the rear diff and replacing it with fresh. Easy to do, see the link below:

http://www.audi-sport.net/vb/a3-s3-forum-8l-chassis/107092-help-rear-diff-oil-quantity.html

In terms of the Haldex, if this was the problem then you'd hear it whether you're going straight or turning. If you want to check it's working, wait until it's raining and turn your ESP off. Then pull away sharply from a standing start on a wet road. Now repeat with fuse 31 removed or the handbrake pulled up ONE notch (to disable the Haldex). You'll find you get s**t loads of front wheelspin with the fuse removed/handbrake up ONE notch compared to with it plugged in!

 

[Welly]

That is very symptomatic of a Haldex service being required.

Either get the kit and do it yourself, or get it to a garage for a Haldex oil and filter change.

I would bet a LOT of money that the problem will be gone afterwards.

 

[Welly]

From what you describe, it sounds like it's more diff-related than Haldex-related to me. If it only does it when turning and is the same in either direction then that points to the diff operation. I'd try draining the oil out of the rear diff and replacing it with fresh. Easy to do, see the link below

Whilst the logic is sound Doc, the Haldex is a weird one. Haldex systems complaining about oil only ever grumble when low speed turning.

Mine did exactly this, as did a mates. Haldex service on both and both problems went.

 

[Lavis89]

i've had this problem for AGES. taken it to a couple garages and had no luck so far. might have to take it to an audi specialist and try out a haldex service, it hurts me hearing a horrid grinding noise every time i turn at slow speed.

 

[Erf]

Take fuse 31 out. If it the noise goes away, you have a haldex issue.

 

[The Doctor]

Hmm, don't understand how this would be Haldex related, but if you've solved it with an oil & filter change Welly, then of course I believe you.

Really easy to do yourself if you have axle stands:

Haldex Oil and Filter Change - How To.

 

[Welly]

Take fuse 31 out. If it the noise goes away, you have a haldex issue.

Not necessarily. You should be changing the Haldex oil and filter every 40K at least anyway. Audi don't recommend doing it for a bit of a laugh.

 

[Welly]

Hmm, don't understand how this would be Haldex related, but if you've solved it with an oil & filter change Welly, then of course I believe you.

Really easy to do yourself if you have axle stands:

Haldex Oil and Filter Change - How To.

I know it sounds odd, but it's true. I didn't think it would make any difference either Doc, but it does. Old Haldex oil just seems to cause groaning from the diff area.

 

[86fran]

Hi guys, thanks for all the advice.

I am pretty hands on when it comes to my cars, but this is the first one I have had with a haldex 4WD system.

The noise appeared to disappear yesterday, however I am not 100% happy as it can't have just happened and fixed itself!

I had the wheels off last night, checked over the brakes/CV's/Wheel bearings etc and couldn't find anything wrong.

I spoke with my cousin (who has had a few 4WD audis) and he also recommended a Haldex service as it only does it a low speed and turning.

My car had the Haldex serviced last year at around 78K. I bought it earlier this year and the car is now about 95k, so I will change the haldex oil and see if anything changes. Where is the best place to get the proper oil from (I don't like my local audi stealer by the way...)

 

[Reesy]

Hi guys, thanks for all the advice.

I am pretty hands on when it comes to my cars, but this is the first one I have had with a haldex 4WD system.

The noise appeared to disappear yesterday, however I am not 100% happy as it can't have just happened and fixed itself!

I had the wheels off last night, checked over the brakes/CV's/Wheel bearings etc and couldn't find anything wrong.

I spoke with my cousin (who has had a few 4WD audis) and he also recommended a Haldex service as it only does it a low speed and turning.

My car had the Haldex serviced last year at around 78K. I bought it earlier this year and the car is now about 95k, so I will change the haldex oil and see if anything changes. Where is the best place to get the proper oil from (I don't like my local audi stealer by the way...)

Go to the next closest one then..

Or TPS

 

[The Doctor]

Or you could order it online. Do the filter while you're at it, and get the filter removal tool because you'll need it.

 

[86fran]

Thanks,

Is eBay the easiest place to get the tool/oil/filter? I'm going to be out of the country for the week so need to order it online.

 

[Radical]

I have a very similar problem with a transmission wind up at parking speed while using lots of lock. Haldex oil and filter changed, diff oil all new and clean, all brakes free and driveshafts ok! Vag com checked for code's and nothing in it. Now I'm lost where to check. Did you solve ur problem and if so what was it? Also as snowy at the moment rear drive is certainly working.

 

[Steven.c]

i used to have this problem on my A3 1.8t FWD, turned out it was my middle section viberating on the car because it has that hanger thats really strange and seems to hit the bracket. only done it at low speeds and when turning left :S worth a look at mate.