Rumble and Vibrations around corners

[JamesW1994]

I'm looking for advice on my 2019 RS3 Sportback.

When going around corners, a rumbling noise accompanied by a vibration spreads throughout the whole car, particularly noticeable on full lock, and it seems to be coming from the rear. Interestingly, this issue only occurs when the car has warmed up to its running temperature. The rumble and vibration occur regardless of whether the throttle is applied or not, and it also happens if I purposely coast in Neutral around a corner (I did this for testing).

The car has 39,000 miles and has undergone two Haldex services, both performed by Audi. It has a full-service history with Audi. Additionally, the car has only been launched four times in its lifetime, as verified by VCDS.

I have attempted a Haldex pump learn on VCDS, this has made no difference

Any suggestions on what might be causing this issue?

Attached is a video with the sound I am hearing.

View: https://youtu.be/HJLeI39JxJs
Sorry about me talking in the clip, I had to send it to the car dealer I purchased it from so was explaining it to them! Thankfully it has a good warranty against it.

 

[flybynite]

If the Haldex service has been done by Audi then get it done again by someone who will take the pump out and inspect/clean the gauze filter. Audi don't do that. Mine had 2 Audi Haldex services and the Haldex oil was as old as the car make of that what you will.

Check all other fluids, front diff oil needs changing now (and every 20K from now on like the 8Y) Make sure rear diff is not empty (not the first dealer to drain the diff on a Haldex service by mistake)

Check the tyres for sawtoothing and possibly swap them side to side (are they staggered or square?)

Sounds a bit like tyre rubbing, worth checking and wheel bearings at the same time. Any spacers or lowering?

 

[JamesW1994]

If the Haldex service has been done by Audi then get it done again by someone who will take the pump out and inspect/clean the gauze filter. Audi don't do that. Mine had 2 Audi Haldex services and the Haldex oil was as old as the car make of that what you will.

Check all other fluids, front diff oil needs changing now (and every 20K from now on like the 8Y) Make sure rear diff is not empty (not the first dealer to drain the diff on a Haldex service by mistake)

Check the tyres for sawtoothing and possibly swap them side to side (are they staggered or square?)

Sounds a bit like tyre rubbing, worth checking and wheel bearings at the same time. Any spacers or lowering?

Thanks for the response! These are all great suggestions, I am booked in with my local garage to have the Haldex pump cleaned. I will swap the wheels around this weekend also.

For me though, I am thinking the Haldex could be a red herring, as I would think that when the car makes the noise in neutral, at that point no power is being delivered to the diff?

But on the flip side of that, why would it only occur when the engine is up to temperature? It’s so strange!

 

[flybynite]

For me though, I am thinking the Haldex could be a red herring, as I would think that when the car makes the noise in neutral, at that point no power is being delivered to the diff?

Although there is no drive, everything is still rotating if the car is moving, just the Haldex clutch packs are disengaged.

But on the flip side of that, why would it only occur when the engine is up to temperature? It’s so strange!

Quite a few other things get up to temp as well, Have you tried warming the engine up standing still?

 

[ClubSandwich]

Sounds like a wheel bearing?

 

[paddy]

Wheel bearing, they dont last long these days i have had 2 sets

 

[vanvan]

If you want to make sure vibration noise is not related to issues with the Haldex, just remove the fuse for the AWD and go for a test drive.

 

[flybynite]

If you want to make sure vibration noise is not related to issues with the Haldex, just remove the fuse for the AWD and go for a test drive.

Pulling the fuse only stops the pump and clutches engaging. Everything is still turning when you drive. It will rule out some Haldex faults but not all

 

[vanvan]

Pulling the fuse only stops the pump and clutches engaging. Everything is still turning when you drive. It will rule out some Haldex faults but not all

Yes, exactly what I said.

 

[vw754]

Any updates with this ?

 

[JamesW1994]

Any updates with this ?

I did eventually get this sorted. We ended up flushing the Haldex fluid twice, which sorted the issue.

We also drained and replaced the diff oil from the separate chamber, although that oil came out clean (still worth checking/replacing, Audi call this oil ‘lifetime oil’ which is utter rubbish… ‘lifetime’ for the car in their eyes!...
Can be purchased from Audi Parts Direct - G052145S2 (same oil used in the transfer box).

Anyways… The first Haldex drain, however, produced a fluid with noticeable metallic glitter in it and crap in it. Worth noting: this car has a full Audi service history and has never missed a diff service interval.

After the first flush the issue improved slightly, and after the second flush it was completely resolved. By that point I had already started a warranty claim, which was approved, so the unit was replaced in the end.

If you experience similar symptoms yourself, I’d recommend you drain both the Haldex and Diff oil into clear containers so you can inspect the condition of the fluid. Perform multiple flushes (driving the car for a bit between changes), and see whether things improve. After this if it’s still not improved chances are it’s a new diff