Knocking sound coming from right rear wheel.

[mk5fsi]

hey guys,

Sorry if this is a double post, lately there has been a knocking sound coming from the rear right wheel, its sort of like a flat Tyre type of sound, it isn't very loud, when you have the music on you can barely hear it. i suspected it was a wheel bearing, however today i took the wheel of to check, and there wasn't any play in wheel, and wen i turned the bearing there was a just a metallic noise that also isn't loud. I also changed the wheels around putting the front wheels at the rear and vice vesa, but the noise is still there. maybe its a wheel bearing but i'm not sure. The car is a 04 golf mk5 2.0 FSI comfort line. Any i ideas?

[Blitzen]

Is it coming from the wheel hub itself, or from the rear suspension? It may be a shock bush, or a suspension mout bush that has perished and on it's way out. The car is 7 years old now, perished bushes may not be discounted as a problem. He'll, my front ones in my polo were gone in less than 3 years!!

[mk5fsi]

I'm Pretty sure its from the wheel hub, because i suspect that if its from the suspension then you can only hear it when its going over bumps, but this is a constant sound, maybe i'm wrong ?

[Rob Burns]

A noisy wheel bearing won't always be loose. I've found one of the best ways to check the rear wheel bearings for noise is to jack up the rear of the car (making sure you have it on jack stands) and spin the wheel in question with one hand while lightly holding the spring with the other. If the wheel bearing is noisy you will feel it through the spring. Also check the other side to compare the two.
Note that this method only works on non-driven wheels.

[mk5fsi]

A noisy wheel bearing won't always be loose. I've found one of the best ways to check the rear wheel bearings for noise is to jack up the rear of the car (making sure you have it on jack stands) and spin the wheel in question with one hand while lightly holding the spring with the other. If the wheel bearing is noisy you will feel it through the spring. Also check the other side to compare the two.
Note that this method only works on non-driven wheels.

Thanks for that, I will give it a shot, as i said i span the wheel, and there was a metallic sound no sort of knock, but i will try your method tomorrow and see how it goes.

[mk5fsi]

Update,

Well I took it down to my local mechanic, and he said that it wasn't the wheel bearings and suggested it is probably the tyres aren't evenly worn, or the car might need to get a wheel balance. Does this sound like a valid cause ?

[buzuki]

Definitly. I find tyre wear is a common problem across the range.

Id get a wheel balance and a wheel alignment. Or swap on 2 good known tyres and see if it disappears.

[bang chong]

Check the inner edge for feathering or lumpiness. It can be caused by poor wheel alignment and not rotating your wheels as often as you should

[mk5fsi]

thanks everyone for your help, well just a quick update, i'm going next to get a wheel alignment, and see if the problem is solved, it seems to be sort of fading away now... maybe i'm just accustomed to it now.

[mk5fsi]

The Problem is finally Fixed, it turned out it was a wheel bearing after all. You had to rotate the wheel really fast to replicate the sound.