Makis

I got a groaning noise from the rear of my S2 and I have no idea what it is. Here are the facts.

1. It happens in all gears and in neutral while costing.
2. Noise appears to change pitch with speeds but seems to be there even at high speeds (100mph although any faster other noises become to laud).
3. When I cost and switch the engine off, the noise is still there so is not engine or steering related.
4. Noise is not affected by depressing the clutch.
5. Noise does not seem to be affected by left/right turns or when breaking.
6. Deceleration acceleration do not really alter the noise in any way.

I have replaced one rear wheel bearing that I thought it may be the noisy one but no difference. I checked the CV joints they seem OK. There is a small play on the inner CV joints but I reackon this is acceptable. I can hear the R&P characteristic high pitch noise which seem to be the same noise I had from day one, so this hopefully is fine. The noise I hear is definetelly of lower pitch then the R&P noise. I am suspecting it could be the Diff bearings but I have not heard here anyone complaining of the diff bearing to go.

Any suggestions? How can I test them?

At the moment I drive it as is and just wait for it to fail (done 2K miles with this noise) but I would like to fix this problem sooner rather then later.

harrisonrick

Did you change the diff fluid? Many say that changing it to a good full synthetic can clear up annoying whines.

Otherwise, could be the pinion gear starting to growl.

FRporscheman

When you did the bearing, did you do it yourself or have a shop do it? Did you/they do both the inner and outer?

It could be the bearing on the other wheel. Ride as passenger and see if it sounds louder/quieter from that side.

Der Cupmeister

If it groans all the time, have someone walk alongside while slowly rolling and see if they can identify a specific side to make sure you changed the correct wheel bearing. Could also be the torque tube bearings going bad.

Makis

Yes, I changed the fluid and opted fro something thicker 80-90SAE instead of the 75-90SAE I had before but no difference.

Will the pinion gear growl when is going. As I said I can still hear the high pitch pinion noise I head in my car from day one. How would I test the pinion gear without removing the transaxel? If I remove the transaxel is it easy for an expert to diagnose the the pinion gear?

On S2 the rear bearing is one piece. I replaced it myself. I have let somebody drive the car when I was outside and could not hear the same noise from outside. Also driving as passenger the noise seem less obvious. I need to drive in as passanger and stay in the rear seat next to see if I can detect anything different.

I was suspecting the torque tube as well. But I don't think the torque tube will growl when I cost and switch off the engine in neutral. Thar said I will probably need to invest in new torque tube bearings at some stage.