Rear wheels making a 'hum-hum-hum' sound?

[Laz]

Had the family in the car earlier and noticed there was a humming sound coming from the rear wheels. Doesn't seem to appear evident when I'm on my own, just with passengers in the back. It's not unbearable but it is noticeable. I'm guessing it's the wheel bearings, or wheel alignment?

What am I looking at with wheel bearing costs from Audi? Is that by any chance included in a Geometric check (wheel alignment) that Audi do?

 

[Blackie]

Check the tyres . Just changed one of mine as it had "staggered" in a castle turret manner on the inside. Sounds like a wheel bearing but isnt
its all nice and quiet again now

 

[Laz]

Tyres are fine mate, besides their tread which is a tad low. Three of them are on 3mm while the back left is on 6mm.

I'm not too worried about that. Another thing I have noticed which is worrying me though is when I reverse out my drive and turn, the wheels almost sound like there's some sort of cranking/creaking noise as if there's something wrong with the front suspensions.

I generally don't have these problems when I've been running the car for a while and then come back a little later. It's more often when the car is cold. Will probably go down to the Audi garage and get them to have a look.

 

[JimC64]

Wheel bearings could be possible....just had Audi quote £293 for a front
Audi Technk doing it tomorrow for £190

Could also be "Sawtooth" effect on the tyres as mentioned?
The tread may be fine but its the way that they have worn.....do a check maybe?

I had a type of grinding / rubbing noise from my fronts.......turned out to be the backplate hitting against the brake disc at times and easily resolved.

 

[Laz]

Wow, I thought it'd cost around 150. Hope it's not, in that case.

Interesting you bring up the grinding noise. I had that once when reversing out. My front right brake disk has these black circles. Could that be the thing you've mentioned?

It's only the front right. The others are all clean.