Wheel bearings or something else?

[johnny_quattro]

I have a similar noise coming from the NSF which groans/rumbles at 30mph and 55-60mph but the noise reduces if I lift off of the accelerator. I'm hoping this is a noisy CV joint/drive shaft. It's been making that noise for over a year or so.

For those who may know some of my history, my gearbox went bang last year and was refurbed by KMS in Carshalton. He did mention a very slight scoring on the crown gear which I understand is the bit that transfers power via the propshaft to the rear wheels, and I'm dearly hoping it's not that, for rather obvious reasons.

Perhaps one of you learned people can advise?

[Cornershop]

So I ended up ordering the whole driveshaft for £50 as based on the my reg-plate, they didnt have a separate inner joint listed for the S8, just the outer joint.

This arrived on Tuesday (having been ordererd 4:45pm Friday), however the part that turned up was too long, so may have been a rear d/s that they sent.

Now apparently, they're adamant they sent me the correct part, so I need to return the part to them at my cost

The garage commented that the part wasn't of equivalent quality, not surprising really at one tenth of the Audi part cost.

Audi part ordered in = 5-6working day delay

Pretty sure, my car has been in the garage longer than its been on my driveway.

[Cornershop]

So car returned with new discs/pads all round, new tie rod ends and inner arms, 4 wheel alignment and new OSF driveshaft.

Although the motorway speed vibration has gone, the rumble still exists. I can at least now ascertain now that it's worse on right hand bends, which I think means the LHS bearing is at fault. The garage however couldn't feel any movement in the up/down plane with the front end jacked up.

Can wheel bearings fail without showing up as movement Once jacked up?

[ainarssems]

Yes. I had rear bearing go noisy on A6. Kept driving probably for another year and more than 10k miles before I could tell which side the noise was coming from, also passed MOT in the meantime. When I finally changed bearing, there was still no movement, just noise got a bit louder and I could tell which side it was from. New bearing and noise was gone.

[Cornershop]

Thanks, looks like more expenditure then.

SKF bearings have a good rep, hoping they're cheaper than Audi

[ainarssems]

I bought genuine Audi item on e-bay for A6, was about £40 for rear bearing and if remember correctly it was made by SKF.

[Cornershop]

SKF bearings arrived, but made in Italy? Thought these were still made in Germany

Could swap for FAG via allgermanparts but unsure where these are made

[Cornershop]

So both front SKF wheel bearings fitted and what a difference. Super smooth, and finally i get the refined cabin experience that i'd hoped for from day one

The driveshaft replacement removed the vibration at speed, so was a probably worthwhile exercise, albeit an expensive one.